1
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Li M, Yang S, Rathi M, Kumar S, Dutcher CS, Grassian VH. Enhanced condensation kinetics in aqueous microdroplets driven by coupled surface reactions and gas-phase partitioning. Chem Sci 2024; 15:13429-13441. [PMID: 39183898 PMCID: PMC11339779 DOI: 10.1039/d4sc03014a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Accepted: 07/17/2024] [Indexed: 08/27/2024] Open
Abstract
Although aqueous microdroplets have been shown to exhibit enhanced chemical reactivity compared to bulk solutions, mechanisms for these enhancements are not completely understood. Here we combine experimental measurements and kinetic modeling to show the strong coupling of interfacial reactions and gas/droplet partitioning in the condensation reaction of pyruvic acid (PA) to yield zymonic acid (ZA) in acidic aqueous microdroplets. Experimental analysis of single microdroplets reveals the substantial influence of evaporation of PA and partitioning of water on the size-, relative humidity (RH)- and temperature-dependent sigmoidal reaction kinetics for the condensation reaction. A newly developed diffusion-reaction-partitioning model is used to simulate the complex kinetics observed in the microdroplets. The model can quantitatively predict the size and compositional changes as the reaction proceeds under different environmental conditions, and provides insights into how microdroplet reactivity is controlled by coupled interfacial reactions and the gas-phase partitioning of PA and water. Importantly, the kinetic model best fits the data when an autocatalytic step is included in the mechanism, i.e. a reaction step where the product, ZA, catalyzes the interfacial condensation reaction. Overall, the dynamic nature of aqueous microdroplet chemistry and the coupling of interfacial chemistry with gas-phase partitioning are demonstrated. Furthermore, autocatalysis of small organic molecules at the air-water interface for aqueous microdroplets, shown here for the first time, has implications for several fields including prebiotic chemistry, atmospheric chemistry and chemical synthesis.
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Affiliation(s)
- Meng Li
- Department of Chemistry and Biochemistry, University of California San Diego La Jolla CA 92093 USA
| | - Shu Yang
- Department of Mechanical Engineering, University of Minnesota Minneapolis MN 55455 USA
| | - Meenal Rathi
- Department of Chemical Engineering and Materials Science, University of Minnesota Minneapolis MN 55455 USA
| | - Satish Kumar
- Department of Chemical Engineering and Materials Science, University of Minnesota Minneapolis MN 55455 USA
| | - Cari S Dutcher
- Department of Mechanical Engineering, University of Minnesota Minneapolis MN 55455 USA
- Department of Chemical Engineering and Materials Science, University of Minnesota Minneapolis MN 55455 USA
| | - Vicki H Grassian
- Department of Chemistry and Biochemistry, University of California San Diego La Jolla CA 92093 USA
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2
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Nilsson JM, Balgoma D, Pettersson C, Lennernäs H, Heindryckx F, Hedeland M. Ammonium bicarbonate buffers combined with hybrid surface technology columns improve the peak shape of strongly tailing lipids. Anal Chim Acta 2024; 1316:342811. [PMID: 38969401 DOI: 10.1016/j.aca.2024.342811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 05/30/2024] [Accepted: 05/31/2024] [Indexed: 07/07/2024]
Abstract
BACKGROUND Lipids such as phosphatidic acids (PAs) and cardiolipins (CLs) present strongly tailing peaks in reversed phase liquid chromatography, which entails low detectability. They are usually analyzed by hydrophilic interaction liquid chromatography (HILIC), which hampers high-throughput lipidomics. Thus, there is a great need for improved analytical methods in order to obtain a broader coverage of the lipidome in a single chromatographic method. We investigated the effect of ammonium bicarbonate (ABC) on peak asymmetry and detectability, in comparison with ammonium formate (AFO) on both a conventional BEH C18 column and an HST-CSH C18 column. RESULTS The combination of 2.5 mM ABC buffer pH 8 with an HST-CSH C18 column produced significantly improved results, reducing the asymmetry factor at 10 % peak height of PA 16:0/18:1 from 8.4 to 1.6. Furthermore, on average, there was up to a 54-fold enhancement in the peak height of its [M - H]- ion compared to AFO and the BEH C18 column. We confirmed this beneficial effect on other strongly tailing lipids, with accessible phosphate moieties e.g., cardiolipins, phosphatidylinositol phosphate, phosphatidylinositol bisphosphate, phosphorylated ceramide and phosphorylated sphingosine. Furthermore, we found an increased detectability of phospho- and sphingolipids up to 28 times in negative mode when using an HST-CSH C18 column. The method was successfully applied to mouse liver samples, where previously undetected endogenous phospholipids could be analyzed with improved chromatographic separation. SIGNIFICANCE In conclusion, the use of 2.5 mM ABC substantially improved the peak shape of PAs and enhanced the detectability of the lipidome in negative mode on an RPLC-ESI-Q-TOF-MS system on both BEH C18 and HST-CSH C18 columns. This method provides a wider coverage of the lipidome with one single injection for future lipidomic applications in negative mode.
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Affiliation(s)
- Jenny M Nilsson
- Department of Medicinal Chemistry, Uppsala Biomedical Centre, Uppsala University, Box 574, 75123 Uppsala, Sweden
| | - David Balgoma
- Department of Medicinal Chemistry, Uppsala Biomedical Centre, Uppsala University, Box 574, 75123 Uppsala, Sweden; Instituto de Biomedicina y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, C/ Sanz y Forés 3, 47003, Valladolid, Spain
| | - Curt Pettersson
- Department of Medicinal Chemistry, Uppsala Biomedical Centre, Uppsala University, Box 574, 75123 Uppsala, Sweden
| | - Hans Lennernäs
- Department of Pharmaceutical Biosciences, Uppsala Biomedical Centre, Uppsala University, Box 591, 75123 Uppsala, Sweden
| | - Femke Heindryckx
- Department of Medical Cell Biology, Uppsala Biomedical Centre, Uppsala University, Box 571, 75123 Uppsala, Sweden
| | - Mikael Hedeland
- Department of Medicinal Chemistry, Uppsala Biomedical Centre, Uppsala University, Box 574, 75123 Uppsala, Sweden.
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3
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Qiu L, Li X, Holden DT, Cooks RG. Reaction acceleration at the surface of a levitated droplet by vapor dosing from a partner droplet. Chem Sci 2024; 15:12277-12283. [PMID: 39118618 PMCID: PMC11304536 DOI: 10.1039/d4sc03528c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 06/30/2024] [Indexed: 08/10/2024] Open
Abstract
Chemical reactions in micrometer-sized droplets can be accelerated by up to six orders of magnitude. However, this acceleration factor (ratio of rate constants relative to bulk) drops to less than 10 for millimeter-sized droplets due to the reduction in surface/volume ratio. To enhance the acceleration in millimeter-sized droplets, we use a new synthesis platform that directly doses reagent vapor onto the reaction droplet surface from a second levitated droplet. Using Katritzky transamination as a model reaction, we made quantitative measurements on size-controlled vapor-dosed droplets, revealing a 31-fold increase in reaction rate constants when examining the entire droplet contents. This enhancement is attributed to a greater reaction rate constant in the droplet surface region (estimated as 105 times greater than that for the bulk). The capability for substantial reaction acceleration in large droplets highlights the potential for rapid synthesis of important chemicals at useful scales. For example, we successfully prepared 23 pyridinium salts within minutes. This efficiency positions droplets as an exceptional platform for rapid, in situ catalyst synthesis. This is illustrated by the preparation of pyridinium salts as photocatalysts and their subsequent use in mediation of amine oxidation both within the same droplet.
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Affiliation(s)
- Lingqi Qiu
- Department of Chemistry, Purdue University 560 Oval Drive West Lafayette Indiana 47907 USA
| | - Xilai Li
- Department of Chemistry, Purdue University 560 Oval Drive West Lafayette Indiana 47907 USA
| | - Dylan T Holden
- Department of Chemistry, Purdue University 560 Oval Drive West Lafayette Indiana 47907 USA
| | - R Graham Cooks
- Department of Chemistry, Purdue University 560 Oval Drive West Lafayette Indiana 47907 USA
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4
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Nandy A, Mondal S, Koner D, Banerjee S. Heavy Water Microdroplet Surface Enriches the Lighter Isotopologue Impurities. J Am Chem Soc 2024; 146:19050-19058. [PMID: 38958201 DOI: 10.1021/jacs.4c03315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Water microdroplets promote unusual chemical reactions at the air-water interface. However, the interfacial structure of water microdroplets and its potential influence on chemical processes are still enigmatic. Here, we present evidence of in-droplet fractionation of water isotopologues. Employing a sonic spray, we atomized the heavy water (D2O, 99.9 atom % D) solution of three classes of organic compounds (basic, acidic, and neutral). The analytes were predominantly desorbed from the resulting droplet surface in protonated form rather than deuterated form, as detected by mass spectrometry. This result remained unaltered upon adding formic acid-d2 (DCOOD) to the droplet. Monitoring Dakin oxidation of benzaldehyde at the surface of binary microdroplets composed of 1:1 (v/v) D2O/H218O revealed the preferred formation of phenolate-16O over phenolate-18O. Atmospheric pressure chemical ionization mass spectrometric analysis of the vapor composition in the sprayed aerosol revealed the preferential evaporation of lighter water isotopologue impurities from the surface of heavy water microdroplets. These results indicate the enrichment of lighter water isotopologue impurities (HOD/H2O) on the surface of heavy water microdroplets, implying possible future developments for water isotopologue fractionation using microdroplets.
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Affiliation(s)
- Abhijit Nandy
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
| | - Supratim Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
| | - Debasish Koner
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi 502284, India
| | - Shibdas Banerjee
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
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5
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Bain RM, Stutzman JR, Pannuto J, Kane M. Characterization of 2-Butanone Peroxide Oligomeric Profiles and Their Associated Gas-Phase and Solution-Phase Rearrangement Products by Electrospray Ionization Mass Spectrometry for Forensic Applications. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:1470-1479. [PMID: 38669013 DOI: 10.1021/jasms.4c00065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
2-Butanone peroxide (also known as methyl ethyl ketone peroxide, MEKP) has applications as a cross-linker in the chemical industry and is also encountered as a homemade primary high explosive; therefore, it is of interest to both process chemists and forensic examiners. Specifically for forensic applications, we demonstrate that when traditional synthetic procedures, available to any hobbyist, are utilized to generate MEKP, oligomeric peroxide units (n ≤ 12), along with several other oligomeric byproduct distributions, are readily observed by liquid chromatography-mass spectrometry (LC-MS). These oligomeric byproducts correspond to the formation of methyl/ethyl ketone end group(s) at the oligomer end group (i.e., loss of ethanol(s) and/or methanol(s) from the oligomer termini). Based on the interpretation of the MS and MS/MS behavior along with the characterization of newly generated terminal alkyl ketone products, we propose that these byproducts are consistent with a Hock-like rearrangement of the primary MEKP distribution in the acidified reaction medium. Following a procedure for homemade preparation, triplicate lots were synthesized. Unique oligomeric and byproduct distributions provided discriminatory power between the synthetic lots. Furthermore, the distributions of MEKP oligomers and the various byproducts in the initiated MEKP match the intensity distributions observed in the intact material with remarkable accuracy. This observation suggests that the postinitiation residue of MEKP could be associated or dissociated from a separately collected intact material obtained during an investigation by examining these oligomeric and byproduct profiles.
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Affiliation(s)
- Ryan M Bain
- The Bureau of Alcohol, Tobacco, Firearms and Explosives, Ammendale, Maryland 20705, United States
| | - John R Stutzman
- The Dow Chemical Company, Midland, Michigan 48667, United States
| | - Julie Pannuto
- The Bureau of Alcohol, Tobacco, Firearms and Explosives, Ammendale, Maryland 20705, United States
| | - Meghan Kane
- The Bureau of Alcohol, Tobacco, Firearms and Explosives, Ammendale, Maryland 20705, United States
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6
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Vannoy KJ, Edwards MQ, Renault C, Dick JE. An Electrochemical Perspective on Reaction Acceleration in Microdroplets. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2024; 17:149-171. [PMID: 38594942 DOI: 10.1146/annurev-anchem-061622-030919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Analytical techniques operating at the nanoscale introduce confinement as a tool at our disposal. This review delves into the phenomenon of accelerated reactivity within micro- and nanodroplets. A decade of accelerated reactivity observations was succeeded by several years of fundamental studies aimed at mechanistic enlightenment. Herein, we provide a brief historical context for rate enhancement in and around micro- and nanodroplets and summarize the mechanisms that have been proposed to contribute to such extraordinary reactivity. We highlight recent electrochemical reports that make use of restricted mass transfer to enhance electrochemical reactions and/or quantitatively measure reaction rates within droplet-confined electrochemical cells. A comprehensive approach to nanodroplet reactivity is paramount to understanding how nature takes advantage of these systems to provide life on Earth and, in turn, how to harness the full potential of such systems.
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Affiliation(s)
- Kathryn J Vannoy
- 1Department of Chemistry, Purdue University, West Lafayette, Indiana, USA;
| | | | - Christophe Renault
- 1Department of Chemistry, Purdue University, West Lafayette, Indiana, USA;
- 2Current Address: Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois, USA
| | - Jeffrey E Dick
- 1Department of Chemistry, Purdue University, West Lafayette, Indiana, USA;
- 3Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana, USA
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7
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Basuri P, Mukhopadhyay S, Reddy KSSVP, Unni K, Spoorthi BK, Shantha Kumar J, Yamijala SSRKC, Pradeep T. Spontaneous α-C-H Carboxylation of Ketones by Gaseous CO 2 at the Air-water Interface of Aqueous Microdroplets. Angew Chem Int Ed Engl 2024; 63:e202403229. [PMID: 38577991 DOI: 10.1002/anie.202403229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/29/2024] [Accepted: 04/02/2024] [Indexed: 04/06/2024]
Abstract
We present a catalyst-free route for the reduction of carbon dioxide integrated with the formation of a carbon-carbon bond at the air/water interface of negatively charged aqueous microdroplets, at ambient temperature. The reactions proceed through carbanion generation at the α-carbon of a ketone followed by nucleophilic addition to CO2. Online mass spectrometry reveals that the product is an α-ketoacid. Several factors, such as the concentration of the reagents, pressure of CO2 gas, and distance traveled by the droplets, control the kinetics of the reaction. Theoretical calculations suggest that water in the microdroplets facilitates this unusual chemistry. Furthermore, such a microdroplet strategy has been extended to seven different ketones. This work demonstrates a green pathway for the reduction of CO2 to useful carboxylated organic products.
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Affiliation(s)
- Pallab Basuri
- DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
| | - Sinchan Mukhopadhyay
- DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
| | - K S S V Prasad Reddy
- Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
| | - Keerthana Unni
- DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
| | - B K Spoorthi
- DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
| | - Jenifer Shantha Kumar
- DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
| | - Sharma S R K C Yamijala
- Centre for Atomistic Modelling and Materials Design, Centre for Molecular Materials and Functions, Centre for Quantum Information, Communication, and Computing, Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
| | - Thalappil Pradeep
- DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, 600036, Chennai, Tamil Nadu, India
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8
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Wilson KR, Prophet AM. Chemical Kinetics in Microdroplets. Annu Rev Phys Chem 2024; 75:185-208. [PMID: 38382571 DOI: 10.1146/annurev-physchem-052623-120718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Micrometer-sized compartments play significant roles in driving heterogeneous transformations within atmospheric and biochemical systems as well as providing vehicles for drug delivery and novel reaction environments for the synthesis of industrial chemicals. Many reports now indicate that reaction kinetics are accelerated under microconfinement, for example, in sprays, thin films, droplets, aerosols, and emulsions. These observations are dramatic, posing a challenge to our understanding of chemical reaction mechanisms with potentially significant practical consequences for predicting the complex chemistry in natural systems. Here we introduce the idea of kinetic confinement, which is intended to provide a conceptual backdrop for understanding when and why microdroplet reaction kinetics differ from their macroscale analogs.
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Affiliation(s)
- Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA;
| | - Alexander M Prophet
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA;
- Department of Chemistry, University of California, Berkeley, California, USA;
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9
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Chen G, Chu F, Zhang S, Li W, Zhou S, Wei W, Chen W, Wang X, Yue L, Feng H, Cui Y, Pan Y. Ortho C-H Bond Activations in an Atmospheric Microwave Plasma Ion Source. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:951-959. [PMID: 38597607 DOI: 10.1021/jasms.4c00011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
C-H bond ortho-substitution reaction has always been a significant and challenging topic in organic chemistry. We proposed a synthesis method based on microwave plasma torches. High-resolution mass spectrometry was used to monitor rapid reaction products. 2-Alkylbenzimidazole can be formed through the reaction of phenylnitrenium ion and nitriles on a millisecond scale. This reaction can achieve the one-step formation of benzimidazoles from benzene ring single-substituted compounds without the addition of external oxidants or catalysts. A similar C-H bond activation reaction can be accomplished with ketones. Meanwhile, the microwave plasma reactor was modified, and the resulting 2-methylbenzimidazole was successfully collected, indicating the device has good application potential in organic reactions such as C-H bond activation reaction.
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Affiliation(s)
- Guanru Chen
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Fengjian Chu
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, P. R. China
| | - Shuheng Zhang
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Wangyu Li
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Shiwen Zhou
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Wei Wei
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Weiwei Chen
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Xiaozhi Wang
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, P. R. China
| | - Lei Yue
- College of Biology, Hunan University, Changsha 410082, Hunan, P. R. China
| | - Hongru Feng
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Yanli Cui
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
| | - Yuanjiang Pan
- Department of Chemistry, Zhejiang University, Hangzhou 310027 Zhejiang, P. R. China
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10
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Heindel JP, LaCour RA, Head-Gordon T. The role of charge in microdroplet redox chemistry. Nat Commun 2024; 15:3670. [PMID: 38693110 DOI: 10.1038/s41467-024-47879-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 04/12/2024] [Indexed: 05/03/2024] Open
Abstract
In charged water microdroplets, which occur in nature or in the lab upon ultrasonication or in electrospray processes, the thermodynamics for reactive chemistry can be dramatically altered relative to the bulk phase. Here, we provide a theoretical basis for the observation of accelerated chemistry by simulating water droplets of increasing charge imbalance to create redox agents such as hydroxyl and hydrogen radicals and solvated electrons. We compute the hydration enthalpy of OH- and H+ that controls the electron transfer process, and the corresponding changes in vertical ionization energy and vertical electron affinity of the ions, to create OH• and H• reactive species. We find that at ~ 20 - 50% of the Rayleigh limit of droplet charge the hydration enthalpy of both OH- and H+ have decreased by >50 kcal/mol such that electron transfer becomes thermodynamically favorable, in correspondence with the more favorable vertical electron affinity of H+ and the lowered vertical ionization energy of OH-. We provide scaling arguments that show that the nanoscale calculations and conclusions extend to the experimental microdroplet length scale. The relevance of the droplet charge for chemical reactivity is illustrated for the formation of H2O2, and has clear implications for other redox reactions observed to occur with enhanced rates in microdroplets.
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Affiliation(s)
- Joseph P Heindel
- Kenneth S. Pitzer Theory Center and Department of Chemistry, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - R Allen LaCour
- Kenneth S. Pitzer Theory Center and Department of Chemistry, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Teresa Head-Gordon
- Kenneth S. Pitzer Theory Center and Department of Chemistry, Berkeley, CA, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Departments of Bioengineering and Chemical and Biomolecular Engineering University of CAlifornia, Berkeley, CA, USA.
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11
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Song Z, Zhu C, Gong K, Wang R, Zhang J, Zhao S, Li Z, Zhang X, Xie J. Deciphering the Microdroplet Acceleration Factors of Aza-Michael Addition Reactions. J Am Chem Soc 2024; 146:10963-10972. [PMID: 38567839 DOI: 10.1021/jacs.4c02312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024]
Abstract
Microdroplet chemistry is emerging as a great tool for accelerating reactions by several orders of magnitude. Several unique properties such as extreme pHs, interfacial electric fields (IEFs), and partial solvation have been reported to be responsible for the acceleration; however, which factor plays the key role remains elusive. Here, we performed quantum chemical calculations to explore the underlying mechanisms of an aza-Michael addition reaction between methylamine and acrylamide. We showed that the acceleration in methanol microdroplets results from the cumulative effects of several factors. The acidic surface of the microdroplet plays a dominating role, leading to a decrease of ∼9 kcal/mol in the activation barrier. We speculated that the dissociation of both methanol and trace water contributes to the surface acidity. An IEF of 0.1 V/Å can further decrease the barrier by ∼2 kcal/mol. Partial solvation has a negligible effect on lowering the activation barrier in microdroplets but can increase the collision frequency between reactants. With acidity revealed to be the major accelerating factor for methanol droplets, reactions on water microdroplets should have even higher rates because water is more acidic. Both theoretically and experimentally, we confirmed that water microdroplets significantly accelerate the aza-Michael reaction, achieving an acceleration factor that exceeds 107. This work elucidates the multifactorial influences on the microdroplet acceleration mechanism, and with such detailed mechanistic investigations, we anticipate that microdroplet chemistry will be an avenue rich in opportunities in the realm of green synthesis.
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Affiliation(s)
- Zhexuan Song
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Chenghui Zhu
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Ke Gong
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Ruijing Wang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Jianze Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Supin Zhao
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Zesheng Li
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Jing Xie
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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12
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Gong K, Meng Y, Zare RN, Xie J. Molecular Mechanism for Converting Carbon Dioxide Surrounding Water Microdroplets Containing 1,2,3-Triazole to Formic Acid. J Am Chem Soc 2024; 146:8576-8584. [PMID: 38488449 DOI: 10.1021/jacs.4c00529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Spraying water microdroplets containing 1,2,3-triazole (Tz) has been found to effectively convert gas-phase carbon dioxide (CO2), but not predissolved CO2, into formic acid (FA). Herein, we elucidate the reaction mechanism at the molecular level through quantum chemistry calculations and ab initio molecular dynamics (AIMD) simulations. Computations suggest a multistep reaction mechanism that initiates from the adsorption of CO2 by Tz to form a CO2-Tz complex (named reactant complex (RC)). Then, the RC either is reduced by electrons that were generated at the air-liquid interface of the water microdroplet and then undergoes intramolecular proton transfer (PT) or switches the reduction and PT steps to form a [HCO2-(Tz-H)]- complex (named PC-). Subsequently, PC- undergoes reduction and the C-N bond dissociates to generate COOH- and [Tz-H]- (m/z = 69). COOH- easily converts to HCOOH and is captured at m/z = 45 in mass spectroscopy. Notably, the intramolecular PT step can be significantly lowered by the oriented electric field at the interface and a water-bridge mechanism. The mechanism is further confirmed by testing multiple azoles. The AIMD simulations reveal a novel proton transfer mechanism where water serves as a transporter and is shown to play an important role dynamically. Moreover, the transient •COOH captured by the experiment is proposed to be partly formed by the reaction with H•, pointing again to the importance of the air-water interface. This work provides valuable insight into the important mechanistic, kinetic, and dynamic features of converting gas-phase CO2 to valuable products by azoles or amines dissolved in water microdroplets.
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Affiliation(s)
- Ke Gong
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yifan Meng
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Jing Xie
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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13
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Martins-Costa MTC, Ruiz-López MF. Reactivity of Monoethanolamine at the Air-Water Interface and Implications for CO 2 Capture. J Phys Chem B 2024; 128:1289-1297. [PMID: 38279927 DOI: 10.1021/acs.jpcb.3c06856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2024]
Abstract
The development of CO2-capture technologies is key to mitigating climate change due to anthropogenic greenhouse gas emissions. These cover a number of technologies designed to reduce the level of CO2 emitted into the atmosphere or to eliminate CO2 from ambient air. In this context, amine-based sorbents in aqueous solutions are broadly used in most advanced separation techniques currently implemented in industrial applications. It has been reported that the gas/liquid interface plays an important role in the early stages of the capture process, but how the interface influences the chemistry is still a matter of debate. With the help of first-principles molecular dynamics simulations, we show that monoethanolamine (MEA), a prototypical sorbent molecule, has a weak affinity for the air-water interface, where in addition it exhibits a lower nucleophilicity compared to bulk solution. The change in reactivity is due to the combination of structural and electronic factors, namely, the shift of the conformational equilibrium and the stabilization of the N-atom lone pair. Based on these results, strategies for improving the efficiency of alkanolamine sorbents are proposed.
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Affiliation(s)
- Marilia T C Martins-Costa
- Laboratoire de Physique et Chimie Théoriques, UMR CNRS 7019, University of Lorraine, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
| | - Manuel F Ruiz-López
- Laboratoire de Physique et Chimie Théoriques, UMR CNRS 7019, University of Lorraine, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
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14
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Devlin SW, Bernal F, Riffe EJ, Wilson KR, Saykally RJ. Spiers Memorial Lecture: Water at interfaces. Faraday Discuss 2024; 249:9-37. [PMID: 37795954 DOI: 10.1039/d3fd00147d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
In this article we discuss current issues in the context of the four chosen subtopics for the meeting: dynamics and nano-rheology of interfacial water, electrified/charged aqueous interfaces, ice interfaces, and soft matter/water interfaces. We emphasize current advances in both theory and experiment, as well as important practical manifestations and areas of unresolved controversy.
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Affiliation(s)
- Shane W Devlin
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Franky Bernal
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Erika J Riffe
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Richard J Saykally
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
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15
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Yang F, Urban RD, Lorenz J, Griebel J, Koohbor N, Rohdenburg M, Knorke H, Fuhrmann D, Charvat A, Abel B, Azov VA, Warneke J. Control of Intermediates and Products by Combining Droplet Reactions and Ion Soft-Landing. Angew Chem Int Ed Engl 2024; 63:e202314784. [PMID: 37917653 DOI: 10.1002/anie.202314784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 11/04/2023]
Abstract
Despite being recognized primarily as an analytical technique, mass spectrometry also has a large potential as a synthetic tool, enabling access to advanced synthetic routes by reactions in charged microdroplets or ionic thin layers. Such reactions are special and proceed primarily at surfaces of droplets and thin layers. Partial solvation of the reactants is usually considered to play an important role for reducing the activation barrier, but many mechanistic details still need to be clarified. In our study, we showcase the synergy between two sequentially applied "preparative mass spectrometry" methods: initiating accelerated reactions within microdroplets during electrospray ionization to generate gaseous ionic intermediates in high abundance, which are subsequently mass-selected and soft-landed to react with a provided reagent on a substrate. This allows the generation of products at a nanomolar scale, amenable to further characterization. In this proof-of-concept study, the contrasting reaction pathways between intrinsically neutral and pre-charged reagents, respectively, both in microdroplets and in layers generated by ion soft-landing are investigated. This provides new insights into the role of partially solvated reagents at microdroplet surfaces for increased reaction rates. Additionally, further insights into reactions of ions of the same polarity under various conditions is obtained.
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Affiliation(s)
- Fangshun Yang
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Raphael D Urban
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Jonas Lorenz
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Jan Griebel
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Nima Koohbor
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Markus Rohdenburg
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstrasse 2, 04103, Leipzig, Germany
| | - Harald Knorke
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstrasse 2, 04103, Leipzig, Germany
| | - Daniel Fuhrmann
- Institute for Inorganic Chemistry, University Leipzig, Johannisallee 29, 04103, Leipzig, Germany
| | - Ales Charvat
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
- Institute of Chemical Technology, University Leipzig, 04103, Leipzig, Germany
| | - Bernd Abel
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
- Institute of Chemical Technology, University Leipzig, 04103, Leipzig, Germany
| | - Vladimir A Azov
- Department of Chemistry, University of the Free State, 9300, Bloemfontein, South Africa
| | - Jonas Warneke
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstrasse 2, 04103, Leipzig, Germany
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16
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Qiu L, Cooks RG. Oxazolone mediated peptide chain extension and homochirality in aqueous microdroplets. Proc Natl Acad Sci U S A 2024; 121:e2309360120. [PMID: 38165938 PMCID: PMC10786291 DOI: 10.1073/pnas.2309360120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 11/20/2023] [Indexed: 01/04/2024] Open
Abstract
Peptide formation from amino acids is thermodynamically unfavorable but a recent study provided evidence that the reaction occurs at the air/solution interfaces of aqueous microdroplets. Here, we show that i) the suggested amino acid complex in microdroplets undergoes dehydration to form oxazolone; ii) addition of water to oxazolone forms the dipeptide; and iii) reaction of oxazolone with other amino acids forms tripeptides. Furthermore, the chirality of the reacting amino acids is preserved in the oxazolone product, and strong chiral selectivity is observed when converting the oxazolone to tripeptide. This last fact ensures that optically impure amino acids will undergo chain extension to generate pure homochiral peptides. Peptide formation in bulk by wet-dry cycling shares a common pathway with the microdroplet reaction, both involving the oxazolone intermediate.
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Affiliation(s)
- Lingqi Qiu
- Department of Chemistry, Purdue University, West Lafayette, IN47907
| | - R. Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, IN47907
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17
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Li K, You W, Wang W, Gong K, Liu Y, Wang L, Ge Q, Ruan X, Ao J, Ji M, Zhang L. Significantly Accelerated Photochemical Perfluorooctanoic Acid Decomposition at the Air-Water Interface of Microdroplets. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21448-21458. [PMID: 38047763 DOI: 10.1021/acs.est.3c05470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
The efficient elimination of per- and polyfluoroalkyl substances (PFASs) from the environment remains a huge challenge and requires advanced technologies. Herein, we demonstrate that perfluorooctanoic acid (PFOA) photochemical decomposition could be significantly accelerated by simply carrying out this process in microdroplets. The almost complete removal of 100 and 500 μg/L PFOA was observed after 20 min of irradiation in microdroplets, while this was achieved after about 2 h in the corresponding bulk phase counterpart. To better compare the defluorination ratio, 10 mg/L PFOA was used typically, and the defluorination rates in microdroplets were tens of times faster than that in the bulk phase reaction system. The high performances in actual water matrices, universality, and scale-up applicability were demonstrated as well. We revealed in-depth that the great acceleration is due to the abundance of the air-water interface in microdroplets, where the reactants concentration enrichment, ultrahigh interfacial electric field, and partial solvation effects synergistically promoted photoreactions responsible for PFOA decomposition, as evidenced by simulated Raman scattering microscopy imaging, vibrational Stark effect measurement, and DFT calculation. This study provides an effective approach and highlights the important roles of air-water interface of microdroplets in PFASs treatment.
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Affiliation(s)
- Kejian Li
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
| | - Wenbo You
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Wei Wang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Kedong Gong
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Yangyang Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Longqian Wang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Qiuyue Ge
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Xuejun Ruan
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Jianpeng Ao
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People's Republic of China
| | - Minbiao Ji
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People's Republic of China
| | - Liwu Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
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18
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Salvitti C, de Petris G, Troiani A, Managò M, Di Noi A, Ricci A, Pepi F. Sulfuric Acid Catalyzed Esterification of Amino Acids in Thin Film. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:2748-2754. [PMID: 37904271 DOI: 10.1021/jasms.3c00284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
The esterification reaction of different amino acids with methanol catalyzed by H2SO4 was first studied in the small volume of thin films generated by ESI microdroplet deposition. The reaction is promoted by the pneumatic spray of the ESI source and reaches its maximum efficiency at a thin film temperature of 70 °C. Selective esterification of the COOH moiety was demonstrated. Microdroplet size and thin film volume and lifetime are critical parameters that influenced the reaction outcome. As expected, l-tyrosine and l-phenylalanine having aromatic side chain substituents were the most reactive amino acids, reaching absolute yields of around 40-50%. The amino acid esterification catalyzed by H2SO4 in a thin film occurs under synthetic conditions in which the same reaction in the bulk is not observed.
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Affiliation(s)
- Chiara Salvitti
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Giulia de Petris
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Anna Troiani
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Marta Managò
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Alessia Di Noi
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Andreina Ricci
- Department of Mathematics and Physics, University of Campania L. Vanvitelli, Viale Lincoln 5, 81100, Caserta, Italy
| | - Federico Pepi
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
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19
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Zheng B, Wu Y, Xue L, Sun J, Liu J, Cheng H. Is Reaction Acceleration of Microdroplet Chemistry Favorable to Controlling the Enantioselectivity? J Org Chem 2023; 88:16186-16195. [PMID: 37948325 DOI: 10.1021/acs.joc.3c01660] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Microdroplet chemistry has been proven to amazingly accelerate many chemical and biological reactions in the past 2 decades. Current microdroplet accelerated reactions are predominantly symmetric synthetic but minorly asymmetric synthetic reactions, where stereoselectivity is scarcely concerned. This study selected unimolecular and bimolecular reactions, multicomponent Passerini reactions, and enzymatic ketone reduction as the model reactions to illustrate whether reaction acceleration of microdroplet chemistry is favorable to retaining a chiral center and controlling the enantioselectivity or not. The results illustrated that microdroplet chemistry did not disrupt pre-existing stereogenic centers in chiral starting materials during reactions but did harm to stereospecificity in asymmetric catalysis by chiral catalysts and chiral organic ligands with the exclusion of enzymatic reactions. Our preliminary study reminds us of more cautions to the product enantioselectivity when conducting asymmetric catalysis in microdroplets. We also hope this study may promote more valuable further research on the stereoselectivity of microdroplet chemistry.
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Affiliation(s)
- Boyu Zheng
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou 311121, China
| | - Yikang Wu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou 311121, China
| | - Luyun Xue
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou 311121, China
| | - Jiannan Sun
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou 311121, China
| | - Jinhua Liu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou 311121, China
| | - Heyong Cheng
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou 311121, China
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20
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Lu SM, Vannoy KJ, Dick JE, Long YT. Multiphase Chemistry under Nanoconfinement: An Electrochemical Perspective. J Am Chem Soc 2023; 145:25043-25055. [PMID: 37934860 DOI: 10.1021/jacs.3c07374] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Most relevant systems of interest to modern chemists rarely consist of a single phase. Real-world problems that require a rigorous understanding of chemical reactivity in multiple phases include the development of wearable and implantable biosensors, efficient fuel cells, single cell metabolic characterization techniques, and solar energy conversion devices. Within all of these systems, confinement effects at the nanoscale influence the chemical reaction coordinate. Thus, a fundamental understanding of the nanoconfinement effects of chemistry in multiphase environments is paramount. Electrochemistry is inherently a multiphase measurement tool reporting on a charged species traversing a phase boundary. Over the past 50 years, electrochemistry has witnessed astounding growth. Subpicoampere current measurements are routine, as is the study of single molecules and nanoparticles. This Perspective focuses on three nanoelectrochemical techniques to study multiphase chemistry under nanoconfinement: stochastic collision electrochemistry, single nanodroplet electrochemistry, and nanopore electrochemistry.
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Affiliation(s)
- Si-Min Lu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P.R. China
| | - Kathryn J Vannoy
- Department of Chemistry, Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jeffrey E Dick
- Department of Chemistry, Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yi-Tao Long
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P.R. China
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21
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Qiu L, Saha M, Kraft S, Dziekonski ET, Welch CJ, Dai Y, Kaerner A, Cooks RG. Quantitative Determination of Water in Organic Liquids by Ambient Mass Spectrometry. Angew Chem Int Ed Engl 2023; 62:e202310884. [PMID: 37740943 DOI: 10.1002/anie.202310884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/31/2023] [Accepted: 09/18/2023] [Indexed: 09/25/2023]
Abstract
This study uses a rapid tandem mass-spectrometry method to determine water content in complex organic solutions. Emphasis is placed on trace-water analysis by a fast and accurate alternative to the Karl-Fischer method. In this new method, water is captured by a charge-labeled molecular probe. Water binds strongly with high specificity to the strongly electrophilic aldehyde site in a charge-labelled molecule (N-methylpyridinium); competitive binding by other analytes is effectively discriminated against in the mass-measurement step. Quantitative determinations are made over a wide concentration range, 0.001 % (10 ppm) to 99 %, with better than 10 % relative standard deviation, along with short (1 min) analysis times using small sample volumes (several μL). Applications include water measurement in simple organic solvents, for example, deuterated solvents, as well as in complex mixtures, for example, organic reaction mixtures. Additionally, this method allows for water monitoring in levitated droplets. Mechanistic investigations into the impact of water on important chemical processes in organic synthesis and environmental science are reported.
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Affiliation(s)
- Lingqi Qiu
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Mousumi Saha
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | | | - Eric T Dziekonski
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Christopher J Welch
- Indiana Consortium for Analytical Science & Engineering (ICASE), Indianapolis, IN 46202, USA
| | - Yumin Dai
- Department of Analytical Development, Takeda Development Center Americas, Inc., Cambridge, MA 02139, USA
| | | | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
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22
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Ju Y, Zhang H, Jiang Y, Wang W, Kan G, Yu K, Wang X, Liu J, Jiang J. Aqueous microdroplets promote C-C bond formation and sequences in the reverse tricarboxylic acid cycle. Nat Ecol Evol 2023; 7:1892-1902. [PMID: 37679455 DOI: 10.1038/s41559-023-02193-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 08/08/2023] [Indexed: 09/09/2023]
Abstract
The reverse tricarboxylic acid cycle (rTCA) is a central anabolic network that uses carbon dioxide (CO2) and may have provided complex carbon substrates for life before the advent of RNA or enzymes. However, non-enzymatic promotion of the rTCA cycle, in particular carbon fixation, remains challenging, even with primordial metal catalysis. Here, we report that the fixation of CO2 by reductive carboxylation of succinate and α-ketoglutarate was achieved in aqueous microdroplets under ambient conditions without the use of catalysts. Under identical conditions, the aqueous microdroplets also facilitated the sequences in the rTCA cycle, including reduction, hydration, dehydration and retro-aldol cleavage and linked with the glyoxylate cycle. These reactions of the rTCA cycle were compatible with the aqueous microdroplets, as demonstrated with two-reaction and four-reaction sequences. A higher selectivity giving higher product yields was also observed. Our results suggest that the microdroplets provide an energetically favourable microenvironment and facilitate a non-enzymatic version of the rTCA cycle in prebiotic carbon anabolism.
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Affiliation(s)
- Yun Ju
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, PR China
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, PR China
| | - Hong Zhang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China.
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, PR China.
| | - Yanxiao Jiang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, PR China
| | - Wenxin Wang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, PR China
| | - Guangfeng Kan
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China
| | - Kai Yu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, PR China
| | - Xiaofei Wang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China
| | - Jilin Liu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, PR China
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, PR China
| | - Jie Jiang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, PR China.
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, PR China.
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, PR China.
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23
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Wang T, Li Z, Gao H, Hu J, Chen HY, Xu JJ. Ultrafast C-C and C-N bond formation reactions in water microdroplets facilitated by the spontaneous generation of carbocations. Chem Sci 2023; 14:11515-11520. [PMID: 37886101 PMCID: PMC10599473 DOI: 10.1039/d3sc03870j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/24/2023] [Indexed: 10/28/2023] Open
Abstract
Carbocations are important electrophilic intermediates in organic chemistry, but their formation typically requires harsh conditions such as extremely low pH, elevated temperature, strong oxidants and/or expensive noble-metal catalysts. Herein, we report the spontaneous generation of highly reactive carbocations in water microdroplets by simply spraying a diarylmethanol aqueous solution. The formation of transient carbocations as well as their ultrafast in-droplet transformations through carbocation-involved C-C and C-N bond formation reactions are directly characterized by mass spectrometry. The intriguing formation and stabilization of carbocations are attributed to the super acidity of the positively charged water microdroplets as well as the high electric fields at the water-air interfaces. Without the utilization of external acids as catalysts, we believe that these microdroplet reactions would pose a new and sustainable way for the construction of aryl-substituted compounds.
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Affiliation(s)
- Ting Wang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210023 P. R. China
| | - Zheng Li
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210023 P. R. China
| | - Hang Gao
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210023 P. R. China
| | - Jun Hu
- School of Life Sciences and Health Engineering, Jiangnan University Wuxi 214122 China
| | - Hong-Yuan Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210023 P. R. China
| | - Jing-Juan Xu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210023 P. R. China
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24
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Li M, Boothby C, Continetti RE, Grassian VH. Size-Dependent Sigmoidal Reaction Kinetics for Pyruvic Acid Condensation at the Air-Water Interface in Aqueous Microdroplets. J Am Chem Soc 2023; 145:22317-22321. [PMID: 37787586 PMCID: PMC10591466 DOI: 10.1021/jacs.3c08249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Indexed: 10/04/2023]
Abstract
The chemistry of pyruvic acid (PA) under thermal dark conditions is limited in bulk solutions, but in microdroplets it is shown to readily occur. Utilizing in situ micro-Raman spectroscopy as a probe, we investigated the chemistry of PA within aqueous microdroplets in a relative humidity- and temperature-controlled environmental cell. We found that PA undergoes a condensation reaction to yield mostly zymonic acid. Interestingly, the reaction follows a size-dependent sigmoidal kinetic profile, i.e., an induction period followed by reaction and then completion. The induction time is linearly proportional to the surface area (R2), and the maximum apparent reaction rate is proportional to the surface-to-volume ratio (1/R), showing that both the induction and reaction occur at the air-water interface. Furthermore, the droplet size is shown to be dynamic due to changes in droplet composition and re-equilibration with the relative humidity within the environmental cell as the reaction proceeds. Overall, the size-dependent sigmoidal kinetics, shown for the first time in microdroplets, demonstrates the complexity of the reaction mechanism and the importance of the air-water interface in the pyruvic acid condensation reaction.
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Affiliation(s)
- Meng Li
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
| | - Christian Boothby
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
| | - Robert E. Continetti
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
| | - Vicki H. Grassian
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
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25
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Heiss DR, Amoah E, Badu-Tawiah AK. Two-dimensional isomer differentiation using liquid chromatography-tandem mass spectrometry with in-source, droplet-based derivatization. Analyst 2023; 148:5270-5278. [PMID: 37740330 PMCID: PMC10696534 DOI: 10.1039/d3an01276j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/24/2023]
Abstract
Saccharides are increasingly used as biomarkers and for therapeutic purposes. Their characterization is challenging due to their low ionization efficiencies and inherent structural heterogeneity. Here, we illustrate how the coupling of online droplet-based reaction, in a form of contained electrospray (ES) ion source, with liquid chromatography (LC) tandem mass spectrometry (MS/MS) allows the comprehensive characterization of sucrose isomers. We used the reaction between phenylboronic acid and cis-diols for on-the-fly derivatization of saccharides eluting from the LC column followed by in situ MS/MS analysis, which afforded diagnostic fragment ions that enabled differentiation of species indistinguishable by chromatography or mass spectrometry alone. For example, chromatograms differing only by 2% in retention times were flagged to be different based on incompatible MS/MS fragmentation patterns. This orthogonal LC-contained-ES-MS/MS method was applied to confirm the presence of turanose, palatinose, maltulose, and maltose, which are structural isomers of sucrose, in three different honey samples. The reported workflow does not require modification to existing mass spectrometers, and the contained-ES platform itself acts both as the ion source and the reactor, all promising widespread application.
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Affiliation(s)
- Derik R Heiss
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
- Battelle Memorial Institute, 505 King Avenue, Columbus, OH, 43201, USA
| | - Enoch Amoah
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
| | - Abraham K Badu-Tawiah
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
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26
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Khuu T, Schleif T, Mohamed A, Mitra S, Johnson MA, Valdiviezo J, Heindel JP, Head-Gordon T. Intra-cluster Charge Migration upon Hydration of Protonated Formic Acid Revealed by Anharmonic Analysis of Cold Ion Vibrational Spectra. J Phys Chem A 2023; 127:7501-7509. [PMID: 37669457 DOI: 10.1021/acs.jpca.3c03971] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
The rates of many chemical reactions are accelerated when carried out in micron-sized droplets, but the molecular origin of the rate acceleration remains unclear. One example is the condensation reaction of 1,2-diaminobenzene with formic acid to yield benzimidazole. The observed rate enhancements have been rationalized by invoking enhanced acidity at the surface of methanol solvent droplets with low water content to enable protonation of formic acid to generate a cationic species (protonated formic acid or PFA) formed by attachment of a proton to the neutral acid. Because PFA is the key feature in this reaction mechanism, vibrational spectra of cryogenically cooled, microhydrated PFA·(H2O)n=1-6 were acquired to determine how the extent of charge localization depends on the degree of hydration. Analysis of these highly anharmonic spectra with path integral ab initio molecular dynamics simulations reveals the gradual displacement of the excess proton onto the water network in the microhydration regime at low temperatures with n = 3 as the tipping point for intra-cluster proton transfer.
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Affiliation(s)
- Thien Khuu
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Tim Schleif
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Ahmed Mohamed
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Sayoni Mitra
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Jesús Valdiviezo
- Pitzer Theory Center, Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Joseph P Heindel
- Pitzer Theory Center, Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Teresa Head-Gordon
- Pitzer Theory Center, Department of Chemistry, University of California, Berkeley, California 94720, United States
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27
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Basuri P, Volmer DA. Detecting Early-Stage Intermediates of Free-Radical Oxidative Degradation in Charged Aqueous Microdroplets. J Phys Chem A 2023; 127:7612-7617. [PMID: 37648376 DOI: 10.1021/acs.jpca.3c04143] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
We report the detection of early-stage intermediates of spontaneous free-radical oxidation of organic pollutants such as aliphatic amino alcohols and diamines in charged aqueous microdroplets in the ambient atmosphere. We propose that the intrinsic formation of reactive oxygen species at the air-water interface is responsible for the radical oxidation of the sp3 carbon. We suggest that our work will aid the understanding of the degradation mechanisms of organic molecules in the environment.
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Affiliation(s)
- Pallab Basuri
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany
| | - Dietrich A Volmer
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany
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28
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Gao Y, Xia B. Microdroplet accelerated reaction for high-efficiency carbon disulfide conversion. Chem Commun (Camb) 2023; 59:10773-10776. [PMID: 37593766 DOI: 10.1039/d3cc03503d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Carbon disulfide (CS2) negatively impacts male sexual function and sperm quality. We propose an efficient method to convert CS2 into dithiocarbamic acid using electrospray ionization, achieving up to 96.7% conversion. Protonated CS2 intermediates (SCSH+) contribute to capturing CO2 in amine reactions. Moreover, the reaction efficiently converts CS2 from ethanol solution using microbubble bursting. This study lays the groundwork for accurate CS2 detection.
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Affiliation(s)
- Yuanji Gao
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, P.R. China.
| | - Bing Xia
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, P.R. China.
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29
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Meng Y, Zare RN, Gnanamani E. One-Step, Catalyst-Free Formation of Phenol from Benzoic Acid Using Water Microdroplets. J Am Chem Soc 2023; 145:19202-19206. [PMID: 37624585 DOI: 10.1021/jacs.3c08638] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
Benzoic acid dissolved in water is electrosprayed (-4 kV) by using nitrogen gas at a pressure of 120 psi to form ∼10 μm diameter microdroplets. Analysis with mass spectrometry (MS) and tandem mass spectrometry (MS2) of the resulting microdroplets shows the direct formation of phenol via decarboxylation without any catalyst or added reagents. This process represents an ecofriendly, environmentally benign method for producing phenol and related aromatic alcohols from their corresponding aromatic acids. The mechanism of this transformation was unambiguously characterized using mass spectrometry, radical trapping, and 18O labeling.
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Affiliation(s)
- Yifan Meng
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Elumalai Gnanamani
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, India
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30
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Ju Y, He Y, Kan G, Yu K, Jiang J, Wang X, Zhang H. Reaction acceleration in microdroplet mass spectrometry: Inlet capillary and solvent composition effects. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2023; 37 Suppl 1:e9498. [PMID: 36852554 DOI: 10.1002/rcm.9498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/27/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
RATIONALE Microdroplet chemistry has attracted tremendous interest in recent years. We have previously reported that microdroplet mass spectrometry (MS) achieves reaction acceleration. Here we systematically investigated the effect of capillary heating of MS inlet and solvent polarity of microdroplets on the conversion ratios of dehydration and phosphorylation reactions. METHODS The micron-sized droplets generated by high-speed gas encapsulated the compounds. The conversion ratios of dehydration and phosphorylation reactions were investigated at different capillary temperatures of MS inlet between 30°C and 300°C. Subsequently, the effects of solvent polarity of different microdroplets (acetonitrile, acetonitrile/water [v/v: 9:1], and water) on microdroplet reactions were investigated. RESULTS The microdroplets could be used as reaction vessels for rapid dehydration and phosphorylation reactions. Microdroplet MS is characterized by the completion of the reaction in microseconds. The increase in capillary temperature increased the conversion ratio of dehydration reactions but had little effect on phosphorylation reactions. The stability of compounds supports this phenomenon. In addition, the increase in solvent polarity in microdroplets promoted the dehydration reaction but inhibited the nucleophilic substitution reaction (phosphorylation reaction). CONCLUSIONS Microdroplet MS achieved an acceleration of the reaction, which was attributed to capillary temperature, microdroplet solvents, and the stability of reaction products. This finding suggested that the inlet capillary and solvent system should be considered in the study and interpretation of microdroplet MS.
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Affiliation(s)
- Yun Ju
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, China
| | - Yuwei He
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, China
| | - Guangfeng Kan
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, China
| | - Kai Yu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
| | - Jie Jiang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
| | - Xiaofei Wang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, China
| | - Hong Zhang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China
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31
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Lin S, Cao LNY, Tang Z, Wang ZL. Size-dependent charge transfer between water microdroplets. Proc Natl Acad Sci U S A 2023; 120:e2307977120. [PMID: 37487062 PMCID: PMC10401017 DOI: 10.1073/pnas.2307977120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 06/26/2023] [Indexed: 07/26/2023] Open
Abstract
Contact electrification (CE) in water has attracted much attention, owing to its potential impacts on the chemical reactions, such as the recent discovery of spontaneous generation of hydrogen peroxide (H2O2) in water microdroplets. However, current studies focus on the CE of bulk water, the measurement of CE between micrometer-size water droplets is a challenge and its mechanism still remains ambiguous. Here, a method for quantifying the amount of charge carried by the water microdroplets produced by ultrasonic atomization is proposed. In the method, the motions of water microdroplets in a uniform electric field are observed and the electrostatic forces on the microdroplets are calculated based on the moving speed of the microdroplets. It is revealed that the charge transfer between water microdroplets is size-dependent. The large microdroplets tend to be positively charged while the small microdroplets tend to receive negative charges, implying that the negative charges transfer from large microdroplets to the small microdroplets during ultrasonic atomization. Further, a theoretical model for microdroplets charging is proposed, in which the curvature-induced surface potential/energy difference is suggested to be responsible for the charge transfer between microdroplets. The findings show that the electric field strength between two microdroplets with opposite charges during separation is strong enough to convert OH‒ to OH*, providing evidence for the CE-induced spontaneous generation of H2O2 in water microdroplets.
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Affiliation(s)
- Shiquan Lin
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing100083, People’s Republic of China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing100049, People’s Republic of China
| | - Leo N. Y. Cao
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing100083, People’s Republic of China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing100049, People’s Republic of China
| | - Zhen Tang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing100083, People’s Republic of China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing100049, People’s Republic of China
| | - Zhong Lin Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing100083, People’s Republic of China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing100049, People’s Republic of China
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA30332−0245
- Yonsei Frontier Lab, Yonsei University, Seoul03722, Republic of Korea
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32
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Brown EK, Rovelli G, Wilson KR. pH jump kinetics in colliding microdroplets: accelerated synthesis of azamonardine from dopamine and resorcinol. Chem Sci 2023; 14:6430-6442. [PMID: 37325131 PMCID: PMC10266468 DOI: 10.1039/d3sc01576a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 05/21/2023] [Indexed: 06/17/2023] Open
Abstract
Recent studies report the dramatic acceleration of chemical reactions in micron-sized compartments. In the majority of these studies the exact acceleration mechanism is unknown but the droplet interface is thought to play a significant role. Dopamine reacts with resorcinol to form a fluorescent product azamonardine and is used as a model system to examine how droplet interfaces accelerate reaction kinetics. The reaction is initiated by colliding two droplets levitated in a branched quadrupole trap, which allows the reaction to be observed in individual droplets where the size, concentration, and charge are carefully controlled. The collision of two droplets produces a pH jump and the reaction kinetics are quantified optically and in situ by measuring the formation of azamonardine. The reaction was observed to occur 1.5 to 7.4 times faster in 9-35 micron droplets compared to the same reaction conducted in a macroscale container. A kinetic model of the experimental results suggests that the acceleration mechanism arises from both the more rapid diffusion of oxygen into the droplet, as well as increased reagent concentrations at the air-water interface.
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Affiliation(s)
- Emily K Brown
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA +1 510-495-2474
- Department of Chemistry, University of California Berkeley CA 94720 USA
| | - Grazia Rovelli
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA +1 510-495-2474
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA +1 510-495-2474
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33
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Zhai Z, Zhou Y, Korovich AG, Hall BA, Yoon HY, Yao Y, Zhang J, Bortner MJ, Roman M, Madsen LA, Edgar KJ. Synthesis and Characterization of Multi-Reducing-End Polysaccharides. Biomacromolecules 2023. [PMID: 37262428 DOI: 10.1021/acs.biomac.3c00104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Site-specific modification is a great challenge for polysaccharide scientists. Chemo- and regioselective modification of polysaccharide chains can provide many useful natural-based materials and help us illuminate fundamental structure-property relationships of polysaccharide derivatives. The hemiacetal reducing end of a polysaccharide is in equilibrium with its ring-opened aldehyde form, making it the most uniquely reactive site on the polysaccharide molecule, ideal for regioselective decoration such as imine formation. However, all natural polysaccharides, whether they are branched or not, have only one reducing end per chain, which means that only one aldehyde-reactive substituent can be added. We introduce a new approach to selective functionalization of polysaccharides as an entrée to useful materials, appending multiple reducing ends to each polysaccharide molecule. Herein, we reduce the approach to practice using amide formation. Amine groups on monosaccharides such as glucosamine or galactosamine can react with carboxyl groups of polysaccharides, whether natural uronic acids like alginates, or derivatives with carboxyl-containing substituents such as carboxymethyl cellulose (CMC) or carboxymethyl dextran (CMD). Amide formation is assisted using the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM). By linking the C2 amines of monosaccharides to polysaccharides in this way, a new class of polysaccharide derivatives possessing many reducing ends can be obtained. We refer to this class of derivatives as multi-reducing-end polysaccharides (MREPs). This new family of derivatives creates the potential for designing polysaccharide-based materials with many potential applications, including in hydrogels, block copolymers, prodrugs, and as reactive intermediates for other derivatives.
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Affiliation(s)
- Zhenghao Zhai
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Yang Zhou
- Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Andrew G Korovich
- Department of Chemistry, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Brady A Hall
- GlycoMIP, Fralin Life Sciences Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Hu Young Yoon
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Yimin Yao
- Department of Chemical Engineering, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Junchen Zhang
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Michael J Bortner
- Department of Chemical Engineering, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Maren Roman
- Department of Sustainable Biomaterials, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Louis A Madsen
- Department of Chemistry, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Kevin J Edgar
- Department of Sustainable Biomaterials, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
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34
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Huang KH, Morato NM, Feng Y, Cooks RG. High-Throughput Diversification of Complex Bioactive Molecules by Accelerated Synthesis in Microdroplets. Angew Chem Int Ed Engl 2023; 62:e202300956. [PMID: 36941213 PMCID: PMC10182919 DOI: 10.1002/anie.202300956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/17/2023] [Accepted: 03/20/2023] [Indexed: 03/23/2023]
Abstract
Late-stage diversification of drug molecules is an important strategy in drug discovery that can be facilitated by reaction screening using high-throughput experimentation. Here we present a rapid method for functionalizing bioactive molecules based on accelerated reactions in microdroplets. Reaction mixtures are nebulized at throughputs better than 1 reaction/second and the accelerated reactions occurring in the microdroplets are followed by desorption electrospray ionization mass spectrometry (DESI-MS). Because the accelerated reactions occur on the millisecond timescale, they allow an overall screening throughput of 1 Hz working at the low nanogram scale. Using this approach, an opioid agonist (PZM21) and an antagonist (naloxone) were diversified using three reactions important in medicinal chemistry: sulfur fluoride exchange (SuFEx) click reactions, imine formation reactions, and ene-type click reactions. Some 269 functionalized analogs of naloxone and PZM21 were generated and characterized by tandem mass spectrometry (MS/MS) after screening over 500 reactions.
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Affiliation(s)
- Kai-Hung Huang
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
| | - Nicolás M Morato
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
| | - Yunfei Feng
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
| | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
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35
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Gong K, Ao J, Li K, Liu L, Liu Y, Xu G, Wang T, Cheng H, Wang Z, Zhang X, Wei H, George C, Mellouki A, Herrmann H, Wang L, Chen J, Ji M, Zhang L, Francisco JS. Imaging of pH distribution inside individual microdroplet by stimulated Raman microscopy. Proc Natl Acad Sci U S A 2023; 120:e2219588120. [PMID: 37155894 PMCID: PMC10193990 DOI: 10.1073/pnas.2219588120] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 03/27/2023] [Indexed: 05/10/2023] Open
Abstract
Aerosol microdroplets as microreactors for many important atmospheric reactions are ubiquitous in the atmosphere. pH largely regulates the chemical processes within them; however, how pH and chemical species spatially distribute within an atmospheric microdroplet is still under intense debate. The challenge is to measure pH distribution within a tiny volume without affecting the chemical species distribution. We demonstrate a method based on stimulated Raman scattering microscopy to visualize the three-dimensional pH distribution inside single microdroplets of varying sizes. We find that the surface of all microdroplets is more acidic, and a monotonic trend of pH decreasing is observed in the 2.9-μm aerosol microdroplet from center to edge, which is well supported by molecular dynamics simulation. However, bigger cloud microdroplet differs from small aerosol for pH distribution. This size-dependent pH distribution in microdroplets can be related to the surface-to-volume ratio. This work presents noncontact measurement and chemical imaging of pH distribution in microdroplets, filling the gap in our understanding of spatial pH in atmospheric aerosol.
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Affiliation(s)
- Kedong Gong
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai200092, People’s Republic of China
| | - Jianpeng Ao
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai200433, Peoples’ Republic of China
- Academy for Engineering and Technology, Fudan University, Shanghai200433, Peoples’ Republic of China
| | - Kejian Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai200092, People’s Republic of China
| | - Le Liu
- Department of Atmospheric and Oceanic Sciences, Fudan University, Shanghai200433, Peoples’ Republic of China
| | - Yangyang Liu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai200092, People’s Republic of China
| | - Guanjun Xu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai200092, People’s Republic of China
| | - Tao Wang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai200092, People’s Republic of China
| | - Hanyun Cheng
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
| | - Zimeng Wang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai200092, People’s Republic of China
| | - Xiuhui Zhang
- Key Laboratory of Cluster Science, Ministry of Education of China, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing100081, Peoples’ Republic of China
| | - Haoran Wei
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI53706
| | - Christian George
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne69626, France
| | - Abdelwahid Mellouki
- Institut de Combustion, Réactivité et Environnement (ICARE), Centre National de la Recherche Scientifique/The Observatory of Sciences of the Universe in the Center (CNRS/OSUC), Orléans Cedex 2, 45071, France
- Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, 43150Benguerir, Morocco
| | - Hartmut Herrmann
- Leibniz Institute for Tropospheric Research, Atmospheric Chemistry Department, Leipzig04318, Germany
| | - Lin Wang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
| | - Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
| | - Minbiao Ji
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai200433, Peoples’ Republic of China
- Academy for Engineering and Technology, Fudan University, Shanghai200433, Peoples’ Republic of China
| | - Liwu Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai200433, Peoples’ Republic of China
- National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Fudan University, Shanghai200433, People’s Republic of China
- Integrated Research on Disaster Risk, and RDR International Center of Excellence on Risk Interconnectivity and Governance on Weather, Fudan University, Shanghai200433, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai200092, People’s Republic of China
| | - Joseph S. Francisco
- Department of Earth and Environmental, Sciences, University of Pennsylvania, Philadelphia, PA19104
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA19104
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36
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Chen CJ, Williams ER. The role of analyte concentration in accelerated reaction rates in evaporating droplets. Chem Sci 2023; 14:4704-4713. [PMID: 37181782 PMCID: PMC10171075 DOI: 10.1039/d3sc00259d] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 04/04/2023] [Indexed: 05/16/2023] Open
Abstract
Accelerated reactions in microdroplets have been reported for a wide range of reactions with some microdroplet reactions occurring over a million times faster than the same reaction in bulk solution. Unique chemistry at the air-water interface has been implicated as a primary factor for accelerated reaction rates, but the role of analyte concentration in evaporating droplets has not been as well studied. Here, theta-glass electrospray emitters and mass spectrometry are used to rapidly mix two solutions on the low to sub-microsecond time scale and produce aqueous nanodrops with different sizes and lifetimes. We demonstrate that for a simple bimolecular reaction where surface chemistry does not appear to play a role, reaction rate acceleration factors are between 102 and 107 for different initial solution concentrations, and these values do not depend on nanodrop size. A rate acceleration factor of 107 is among the highest reported and can be attributed to concentration of analyte molecules, initially far apart in dilute solution, but brought into close proximity in the nanodrop through evaporation of solvent from the nanodrops prior to ion formation. These data indicate that analyte concentration phenomenon is a significant factor in reaction acceleration where droplet volume throughout the experiment is not carefully controlled.
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Affiliation(s)
- Casey J Chen
- Department of Chemistry, University of California Berkeley CA 94720 USA
| | - Evan R Williams
- Department of Chemistry, University of California Berkeley CA 94720 USA
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37
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Wang J, Huang D, Chen F, Chen J, Jiang H, Zhu Y, Chen C, Zhao J. Rapid Redox Cycling of Fe(II)/Fe(III) in Microdroplets during Iron-Citric Acid Photochemistry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:4434-4442. [PMID: 36883325 DOI: 10.1021/acs.est.2c07897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Fe(III) and carboxylic acids are common compositions in atmospheric microdroplet systems like clouds, fogs, and aerosols. Although photochemical processes of Fe(III)-carboxylate complexes have been extensively studied in bulk aqueous solution, relevant information on the dynamic microdroplet system, which may be largely different from the bulk phase, is rare. With the help of the custom-made ultrasonic-based dynamic microdroplet photochemical system, this study examines the photochemical process of Fe(III)-citric acid complexes in microdroplets for the first time. We find that when the degradation extent of citric acid is similar between the microdroplet system and the bulk solution, the significantly lower Fe(II) ratio is present in microdroplet samples due to the rapider reoxidation of photogenerated Fe(II). However, by replacing citric acid with benzoic acid, no much difference in the Fe(II) ratio between microdroplets and bulk solution is observed, which indicates distinct reoxidation pathways of Fe(II). Moreover, the presence of •OH scavenger, namely, methanol, greatly accelerates the reoxidation of photogenerated Fe(II) in both citric acid and benzoic acid situations. Further experiments reveal that the high availability of O2 and the citric acid- or methanol-derived carbon-centered radicals are responsible for the rapider reoxidation of Fe(II) in iron-citric acid microdroplets by prolonging the length of HO2•- and H2O2-involved radical reaction chains. The results in this study may provide a new understanding about iron-citric acid photochemistry in atmospheric liquid particles, which can further influence the photoactivity of particles and the formation of secondary organic aerosols.
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Affiliation(s)
- Jinzhao Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Di Huang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Fengxia Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jianhua Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hongyu Jiang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yifan Zhu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chuncheng Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jincai Zhao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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38
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Ju Y, Zhang H, Wang X, Liu Y, Yang Y, Kan G, Yu K, Jiang J. Abiotic synthesis with plausible emergence for primitive phospholipid in aqueous microdroplets. J Colloid Interface Sci 2023; 634:535-542. [PMID: 36549202 DOI: 10.1016/j.jcis.2022.12.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 10/08/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022]
Abstract
Phospholipids are the protective layer of modern cells, but it is challenging for the formation of phospholipids that require a simple abiotic synthesis before the advent of primitive cells. Here, we reported the abiotic synthesis for lysophosphatidic acids (LPAs) with prebiotically plausible reactants in aqueous microdroplets under ambient conditions. The LPAs formation is carried out by fusing two microdroplets streams: one contains glycerol and pyrophosphate in water and the other one contains fatty acids in acetonitrile. Compared with the bulk solution, LPAs were generated in microdroplets without the addition of catalyst and heating. Conditions of reactant concentrations and microdroplet size varied and suggested that LPAs formation occurred near or at the microdroplet surface. The LPAs formation also showed chemoselective toward on chain-length of fatty acids. Finally, the formation of LPAs underwent two-step reactions with glycerol phosphorylation eliminating one water molecule followed by esterification with fatty acids. These results also implicated that pyrophosphate functioned as both catalysts and precursors in prebiotic LPAs synthesis. The approach using fusion aqueous microdroplets has desirable features in studying the substance exchange and interaction in atmosphere.
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Affiliation(s)
- Yun Ju
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China; School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150090, PR China
| | - Hong Zhang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, PR China.
| | - Xiaofei Wang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China
| | - Yaqi Liu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China
| | - Yali Yang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China; School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150090, PR China
| | - Guangfeng Kan
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China
| | - Kai Yu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, PR China
| | - Jie Jiang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, PR China; School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150090, PR China.
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39
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Jin X, Wu Y, Dai C, Sun J, Ye M, Liu J, Cheng H. Catalyst-Free Accelerated Three-Component Synthesis of Betti Bases in Microdroplets. Chempluschem 2023; 88:e202200206. [PMID: 36026555 DOI: 10.1002/cplu.202200206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/28/2022] [Indexed: 02/03/2023]
Abstract
Due to their important roles in medicine and asymmetric metal catalysis, the formation of Betti bases has attracted wide interest in organic chemical community. Traditional multicomponent reaction methods for synthesizing Betti bases normally require long reaction times under harsh conditions (high temperature, microwave or ultrasonic irradiation, etc.) in the presence of various catalysts. In this study, we developed a mild, highly efficient and environmentally friendly method to synthesize Betti bases without the use of any catalysts in microdroplets. The Betti reaction was accelerated by 6.53×103 in microdroplets by comparing the measured rate constant in bulk. Fifteen Betti bases were synthesized by the microdroplet method using a variety of aldehydes, naphthols and amines with 68-98 % yields at a scaled-up amount of 1.9 g h-1 . Overall it is an attractive alternative to classic organic synthesis for the construction of Betti bases and derivatives.
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Affiliation(s)
- Xiaoxiao Jin
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China
| | - Yikang Wu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China
| | - Chengbiao Dai
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China
| | - Jiannan Sun
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China
| | - Meiying Ye
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China
| | - Jinhua Liu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China
| | - Heyong Cheng
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Hangzhou Normal University, 2318 Yuhangtang Road, Hangzhou, 311121, P. R. China
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40
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Meng Y, Gnanamani E, Zare RN. Catalyst-Free Decarboxylative Amination of Carboxylic Acids in Water Microdroplets. J Am Chem Soc 2023; 145:32-36. [PMID: 36566437 DOI: 10.1021/jacs.2c12236] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Previous studies have shown that hydroxyl radicals can be formed at the water-gas surface of water microdroplets. We report the use of in situ generated hydroxyl radicals to carry out an organic transformation in one step, namely, the formation of anilines from aryl acids as well as both ammonia and primary/secondary amines via decarboxylation. Benzoic acids and amines are dissolved in water, and the solution is sprayed to form microdroplets whose chemical contents are analyzed mass spectrometrically. All intermediates and products are determined using mass spectrometry (MS) as well as in some cases tandem mass spectrometry (MS2). These results support the following reaction mechanism: NR2OH, formed via reaction of the amine with •OH, reacts with benzoic acid to form an isocyanate via a Lossen rearrangement. Hydrolysis followed by liberation of CO2 then delivers the aniline product. Notably, the scope of this transformation includes a variety of amines and aromatic acids and enables their conversion into aniline and N-substituted anilines, all in a single step. Additionally, this reaction occurs at room temperature and does not require metal catalysts or organic solvents.
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Affiliation(s)
- Yifan Meng
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Elumalai Gnanamani
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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41
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Efficiency in CO2-utilization strategies: The case of styrene carbonate synthesis in microdroplets conditions. J CO2 UTIL 2023. [DOI: 10.1016/j.jcou.2022.102328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Gao Y, He Q, Guo C, Chen W, Pan Y. Carbon Dioxide Microbubble Bursting Ionization Mass Spectrometry. Anal Chem 2022; 94:17360-17364. [PMID: 36473082 DOI: 10.1021/acs.analchem.2c03518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Aerosols generated by bubble bursting have been proved to promote the extraction of analytes and have ultrahigh electric fields at their water-air interfaces. This study presented a simple and efficient ionization method, carbon dioxide microbubble bursting ionization (CDMBI), without the presence of an exogenous electric field (namely, zero voltage), by simulating the interfacial chemistries of sea spray aerosols. In CDMBI, microbubbles are generated in situ by continuous input of carbon dioxide into an aqueous solution containing low-concentration analytes. The microbubbles extract low- and high-polarity analytes as they pass through the aqueous solution. Upon reaching the water-air interface, these microbubbles burst to produce charged aerosol microdroplets with an average diameter of 260 μm (8.1-10.4 nL in volume), which are immediately transferred to a mass spectrometer for the detection and identification of extracted analytes. The above analytical process occurs every 4.2 s with a stable total ion chromatogram (relative standard deviation: 9.4%) recorded. CDMBI mass spectrometry (CDMBI-MS) can detect surface-active organic compounds in aerosol microdroplets, such as perfluorooctanoic acid, free fatty acids epoxidized by bubble bursting, sterols, and lecithins in soybean and egg, with the limit of detection reaching the level of fg/mL. In addition, coupling CDMBI-MS with an exogenous voltage yields relatively weak gains in ionization efficiency and sensitivity of analysis. The results suggested that CDMBI can simultaneously accomplish both bubbling extraction and microbubble bursting ionization. The mechanism of CDMBI involves bubbling extraction, proton transfer, inlet ionization, and electrospray-like ionization. Overall, CDMBI-MS can work in both positive and negative ion modes without necessarily needing an exogenous high electric field for ionization and quickly detect trace surface-active analytes in aqueous solutions.
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Affiliation(s)
- Yuanji Gao
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang310027, P. R. China.,College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, Sichuan610068, P. R. China
| | - Quan He
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang310027, P. R. China
| | - Cheng Guo
- Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, Ministry of Education), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang310009, P. R. China
| | - Weiwei Chen
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang310027, P. R. China
| | - Yuanjiang Pan
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang310027, P. R. China
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43
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Ghosh J, Mendoza J, Cooks RG. Accelerated and Concerted Aza-Michael Addition and SuFEx Reaction in Microdroplets in Unitary and High-Throughput Formats. Angew Chem Int Ed Engl 2022; 61:e202214090. [PMID: 36253886 PMCID: PMC10099520 DOI: 10.1002/anie.202214090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Indexed: 11/12/2022]
Abstract
The sulfur fluoride exchange (SuFEx) reaction is significant in drug discovery, materials science, and chemical biology. Conventionally, it involves installation of SO2 F followed by fluoride exchange by a catalyst. We report catalyst-free Aza-Michael addition to install SO2 F and then SuFEx reaction with amines, both occurring in concert, in microdroplets under ambient conditions. The microdroplet reaction is accelerated by a factor of ∼104 relative to the corresponding bulk reaction. We suggest that the superacidic microdroplet surface assists SuFEx reaction by protonating fluorine to create a good leaving group. The reaction scope was established by performing individual reactions in microdroplets of 18 amines in four solvents and confirmed using high-throughput desorption electrospray ionization experiments. The study demonstrates the value of microdroplet-assisted accelerated reactions in combination with high-throughput experimentation for characterization of reaction scope.
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Affiliation(s)
- Jyotirmoy Ghosh
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907, USA
| | - Joshua Mendoza
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907, USA
| | - R Graham Cooks
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907, USA
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44
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Deal AM, Vaida V. Infrared Reflection–Absorption Spectroscopy of α-Hydroxyacids at the Water–Air Interface. J Phys Chem A 2022; 126:8280-8294. [DOI: 10.1021/acs.jpca.2c04462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexandra M. Deal
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Veronica Vaida
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
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45
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Holden DT, Morato NM, Cooks RG. Aqueous microdroplets enable abiotic synthesis and chain extension of unique peptide isomers from free amino acids. Proc Natl Acad Sci U S A 2022; 119:e2212642119. [PMID: 36191178 PMCID: PMC9586328 DOI: 10.1073/pnas.2212642119] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 08/27/2022] [Indexed: 12/13/2022] Open
Abstract
Amide bond formation, the essential condensation reaction underlying peptide synthesis, is hindered in aqueous systems by the thermodynamic constraints associated with dehydration. This represents a key difficulty for the widely held view that prebiotic chemical evolution leading to the formation of the first biomolecules occurred in an oceanic environment. Recent evidence for the acceleration of chemical reactions at droplet interfaces led us to explore aqueous amino acid droplet chemistry. We report the formation of dipeptide isomer ions from free glycine or L-alanine at the air-water interface of aqueous microdroplets emanating from a single spray source (with or without applied potential) during their flight toward the inlet of a mass spectrometer. The proposed isomeric dipeptide ion is an oxazolidinone that takes fully covalent and ion-neutral complex forms. This structure is consistent with observed fragmentation patterns and its conversion to authentic dipeptide ions upon gentle collisions and for its formation from authentic dipeptides at ultra-low concentrations. It also rationalizes the results of droplet fusion experiments that show that the dipeptide isomer facilitates additional amide bond formation events, yielding authentic tri- through hexapeptides. We propose that the interface of aqueous microdroplets serves as a drying surface that shifts the equilibrium between free amino acids in favor of dehydration via stabilization of the dipeptide isomers. These findings offer a possible solution to the water paradox of biopolymer synthesis in prebiotic chemistry.
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Affiliation(s)
- Dylan T. Holden
- Department of Chemistry, Purdue University, West Lafayette, IN 47907
| | - Nicolás M. Morato
- Department of Chemistry, Purdue University, West Lafayette, IN 47907
| | - R. Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, IN 47907
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46
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Qiu L, Cooks RG. Simultaneous and Spontaneous Oxidation and Reduction in Microdroplets by the Water Radical Cation/Anion Pair. Angew Chem Int Ed Engl 2022; 61:e202210765. [PMID: 35994573 PMCID: PMC9825976 DOI: 10.1002/anie.202210765] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Indexed: 01/11/2023]
Abstract
Microdroplets show unique chemistry, especially in their intrinsic redox properties, and to this we here add a case of simultaneous and spontaneous oxidation and reduction. We report the concurrent conversions of several phosphonates to phosphonic acids by reduction (R-P → H-P) and to pentavalent phosphoric acids by oxidation. The experimental results suggest that the active reagent is the water radical cation/anion pair. The water radical cation is observed directly as the ionized water dimer while the water radical anion is only seen indirectly though the spontaneous reduction of carbon dioxide to formate. The coexistence of oxidative and reductive species in turn supports the proposal of a double-layer structure at the microdroplet surface, where the water radical cation and radical anion are separated and accumulated.
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Affiliation(s)
- Lingqi Qiu
- Department of ChemistryPurdue University560 Oval. Dr.West LafayetteIN 47907USA
| | - R. Graham Cooks
- Department of ChemistryPurdue University560 Oval. Dr.West LafayetteIN 47907USA
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47
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Heiss DR, Badu-Tawiah AK. Liquid Chromatography-Tandem Mass Spectrometry with Online, In-Source Droplet-Based Phenylboronic Acid Derivatization for Sensitive Analysis of Saccharides. Anal Chem 2022; 94:14071-14078. [PMID: 36179275 DOI: 10.1021/acs.analchem.2c03736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability to identify abnormalities in the body's saccharide profile is a promising means for early disease detection but requires analytical tools capable of detecting saccharides at low concentrations and/or for volume-limited samples. The preferred analysis approach for these compounds, liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), often lacks sensitivity due to poor ionization efficiency. In this work, we employ a modified electrospray interface-termed contained-electrospray (contained-ESI) to couple accelerated droplet chemistry to conventional LC-MS for the online and automated separation, derivatization, and detection of saccharides. The chromatographic component enables complex sample and mixtures analysis with low sample volume requirements, while the enhanced reaction kinetics afforded by electrosprayed microdroplets facilitates rapid, on-the-fly derivatization to boost sensitivity. Derivatization occurs during ion formation as analytes elute from the column, eliminating the need for superfluous post-column derivatization hardware or complicated benchtop protocols. A grounded coupler was incorporated to shield the LC from the high-voltage ion source, and method conditions were optimized to accommodate the low flow rates preferred for microdroplet reactions. The new LC-contained-ESI-MS/MS platform was demonstrated for the analysis of several mono-, di-, and oligosaccharides using in-source droplet-based phenylboronic acid derivatization. Femtomole limits of detection were achieved for a 1 μL injection, representing sensitivity enhancement of 1-2 orders of magnitude over conventional LC-ESI-MS/MS without derivatization. In addition, isobaric saccharides that are difficult to differentiate by MS alone were easily distinguished. Method precision, accuracy, and linearity were established, and the ability to detect oligosaccharides at trace levels in human urine and plasma was demonstrated.
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Affiliation(s)
- Derik R Heiss
- Department of Chemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio43210, United States.,Battelle Memorial Institute, Columbus, Ohio43201, United States
| | - Abraham K Badu-Tawiah
- Department of Chemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio43210, United States
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48
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Song X, Meng Y, Zare RN. Spraying Water Microdroplets Containing 1,2,3-Triazole Converts Carbon Dioxide into Formic Acid. J Am Chem Soc 2022; 144:16744-16748. [PMID: 36075012 DOI: 10.1021/jacs.2c07779] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We report the use of 1,2,3-triazole (Tz)-containing water microdroplets for gas-phase carbon dioxide (CO2) reduction at room temperature. Using a coaxial sonic spraying setup, the CO2 can be efficiently captured by Tz and converted to formic acid (HCOOH; FA) at the gas-liquid interface (GLI). A mass spectrometer operated in negative ion mode monitors the capture of CO2 to form the bicarbonate anion (HCO3-) and conversion to form the formate anion (HCOO-). Varied FA species were successfully identified by MS/MS experiments including the formate monomer ([FA - H]-, m/z 45), the dimer ([2FA - H]-, m/z 91; [2FA + Na - 2H]-, m/z 113), the trimer ([3FA - H]-, m/z 137), and some other adducts (such as [FA - H + H2CO3]-, m/z 107; [2FA + Na - 2H + Tz]-, m/z 182). The reaction conditions were systematically optimized to make the maximum conversion yield reach over 80% with an FA concentration of approximately 71 ± 3.1 μM. The mechanism for the reaction is speculated to be that Tz donates the proton and the hydroxide (OH-) at the GLI, resulting in a stepwise yield of electrons to reduce gas-phase CO2 to FA.
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Affiliation(s)
- Xiaowei Song
- Department of Chemistry, Stanford University, Stanford, California 94305 United States
| | - Yifan Meng
- Department of Chemistry, Stanford University, Stanford, California 94305 United States
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305 United States
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49
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He J, Zhang H, Wang W, Ma Y, Yang M, He Y, Liu Z, Yu K, Jiang J. Probing autoxidation of oleic acid at air-water interface: A neglected and significant pathway for secondary organic aerosols formation. ENVIRONMENTAL RESEARCH 2022; 212:113232. [PMID: 35398317 DOI: 10.1016/j.envres.2022.113232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 02/27/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
Fatty acids have been proposed to be a potential source of precursors for SOAs, but the autoxidation process was neglected in the oxidation studies. Here, the autoxidation of oleic acid was explored using microdroplet mass spectrometry. Bulk solution, concentration and solvent composition experiments provided direct evidences for that the autoxidation occurred at or near the air-water interface. The kinetic data showed an acceleration at this interface and was comparable to ozonation, indicating that autoxidation is an important pathway for SOAs formation. In addition, intermediates/products were captured and identified using tandem mass spectrometry, spin-trapping and quenched agents. The autoxidation mechanism was divided into addition intermediates (AIs) and Criegee intermediates (CIs) pathways mediated by hydroxyl radicals (OH). The CI chemistry which is ubiquitous in gas phase was observed at the air-water interface, and this leaded to the mass/volume loss of aerosols. Inversely, the AI chemistry caused the increase of mass, density and hygroscopicity of aerosols. AI chemistry was dominated compared to CI chemistry, but varied by concerning aerosol sizes, ultraviolet light (UV) and charge. Moreover, the MS approach of selectively probing the interfacial substances at the scale of sub-seconds opens new opportunities to study heterogeneous chemistry in atmosphere.
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Affiliation(s)
- Jing He
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China
| | - Hong Zhang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, PR China.
| | - Wenxin Wang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China
| | - Yingxue Ma
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China
| | - Miao Yang
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China
| | - Yuwei He
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China
| | - Zhuo Liu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China
| | - Kai Yu
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong, 264209, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China
| | - Jie Jiang
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, 150090, PR China.
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Qiu L, Cooks RG. Simultaneous and Spontaneous Oxidation and Reduction in Microdroplets by the Water Radical Cation/Anion Pair. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202210765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Lingqi Qiu
- Purdue University Chemistry UNITED STATES
| | - R Graham Cooks
- Purdue University Chemistry 560 Oval Drive 47907 West Lafayette UNITED STATES
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