1
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Sano M, Kamei K, Yatsuhashi T, Sakota K. Localization and Orientation of Dye Molecules at the Surface of a Levitated Microdroplet in Air Revealed by Whispering Gallery Mode Resonances. J Phys Chem Lett 2024; 15:8133-8141. [PMID: 39087939 DOI: 10.1021/acs.jpclett.4c01819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
Microdroplets offer unique environments that accelerate chemical reactions; however, the mechanisms behind these processes remain debated. The localization and orientation of solute molecules near the droplet surface have been proposed as factors for this acceleration. Since significant reaction acceleration has been observed for electrospray- and sonic-spray-generated aerosol droplets, the analysis of microdroplets in air has become essential. Here, we utilized whispering gallery mode (WGM) resonances to investigate the localization and orientation of dissolved rhodamine B (RhB) in a levitated microdroplet (∼3 μm in diameter) in air. Fluorescence enhancement upon resonance with the WGMs revealed the localization and orientation of RhB near the droplet surface. Numerical modeling using Mie theory quantified the RhB orientation at 68° to the surface normal, with a small fraction randomly oriented inside the droplet. Additionally, low RhB concentrations increased surface localization. These results support the significance of surface reactions in the acceleration of microdroplet reactions.
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Affiliation(s)
- Motoya Sano
- Division of Molecular Material Science, Graduate School of Science, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Kota Kamei
- Division of Molecular Material Science, Graduate School of Science, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Tomoyuki Yatsuhashi
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Kenji Sakota
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
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2
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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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3
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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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4
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Wang K, Pera-Titus M. Microstructured gas-liquid-(solid) interfaces: A platform for sustainable synthesis of commodity chemicals. SCIENCE ADVANCES 2024; 10:eado5448. [PMID: 38809985 PMCID: PMC11135396 DOI: 10.1126/sciadv.ado5448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 04/25/2024] [Indexed: 05/31/2024]
Abstract
Gas-liquid-solid catalytic reactions are widespread in nature and man-made technologies. Recently, the exceptional reactivity observed on (electro)sprayed microdroplets, in comparison to bulk gas-liquid systems, has attracted the attention of researchers. In this perspective, we compile possible strategies to engineer catalytically active gas-liquid-(solid) interfaces based on membrane contactors, microdroplets, micromarbles, microbubbles, and microfoams to produce commodity chemicals such as hydrogen peroxide, ammonia, and formic acid. In particular, particle-stabilized microfoams, with superior upscaling capacity, emerge as a promising and versatile platform to conceive high-performing (catalytic) gas-liquid-(solid) nanoreactors. Gas-liquid-(solid) nanoreactors could circumvent current limitations of state-of-the-art multiphase reactors (e.g., stirred tanks, trickle beds, and bubble columns) suffering from poor gas solubility and mass transfer resistances and access gas-liquid-(solid) reactors with lower cost and carbon footprint.
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Affiliation(s)
- Kang Wang
- Cardiff Catalysis Institute, Cardiff University, Cardiff CF10 3AT, UK
| | - Marc Pera-Titus
- Cardiff Catalysis Institute, Cardiff University, Cardiff CF10 3AT, UK
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5
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Chen H, Wang R, Chiba T, Foreman K, Bowen K, Zhang X. Designer "Quasi-Benzyne": The Spontaneous Reduction of Ortho-Diiodotetrafluorobenzene on Water Microdroplets. J Am Chem Soc 2024; 146:10979-10983. [PMID: 38586980 DOI: 10.1021/jacs.4c02819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
It has been widely shown that water microdroplets have a plethora of unique properties that are highly distinct from those of bulk water, among which an especially intriguing one is the strong reducing power as a result of the electrons spontaneously generated at the air-water interface. In this study, we take advantage of the reducing power of water microdroplets to reduce ortho-diiodotetrafluorobenzene (o-C6F4I2) into a C6F4I2•- radical anion. Photoelectron spectroscopy and density functional theory computations reveal that the excess electron in C6F4I2•- occupies the I-C1-C2-I linkage, which elongates the C-I bonds but surprisingly shortens the C1-C2 bond, making the bond order higher than a double bond, similar to the benzyne molecule, so we named it "quasi-benzyne". The C6F4I2•- anion was further successfully utilized in a Diels-Alder reaction, a typical reaction for benzyne. This study provides a good example of strategically utilizing the spontaneous properties of water microdroplets and generating an especially exotic anion, and we anticipate that microdroplet chemistry can be an avenue rich in opportunities for new catalyst-free organic reactions.
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Affiliation(s)
- Huan Chen
- 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, Tianjin300071, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin300192, 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, Tianjin300071, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin300192, China
| | - Tatsuya Chiba
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kathryn Foreman
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kit Bowen
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - 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, Tianjin300071, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin300192, China
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6
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Rodriguez HM, Martyniuk M, Iyer KS, Ciampi S. Insulator-on-Conductor Fouling Amplifies Aqueous Electrolysis Rates. J Am Chem Soc 2024; 146:10299-10311. [PMID: 38591156 DOI: 10.1021/jacs.3c11238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
The chemical industry is a major consumer of fossil fuels. Several chemical reactions of practical value proceed with the gain or loss of electrons, opening a path to integrate renewable electricity into chemical manufacturing. However, most organic molecules have low aqueous solubility, causing green and cheap electricity-driven reactions to suffer from intrinsically low reaction rates in industry's solvent of choice: water. Here, we show that a strategic, partial electrode fouling with hydrophobic insulators (oils and plastics) offsets kinetic limitations caused by poor reactant solubility, opening a new path for the direct integration of renewable electricity into the production of commodity chemicals. Through electrochemiluminescence microscopy, we reveal for the oxidation of organic reactants up to 6-fold reaction rate increase at the "fouled" oil-electrolyte-electrode interface relative to clean electrolyte-electrode areas. Analogously, electrodes partially masked (fouled) with plastic patterns, deposited either photolithographically (photoresists) or manually (inexpensive household glues and sealants), outperform clean electrodes. The effect is not limited to reactants of limited water solubility, and, for example, net gold electrodeposition rates are up to 22% larger at fouled than clean electrodes. In a system involving a surface-active reactant, rate augmentation is driven by the synergy between insulator-confined reactant enrichment and insulator-induced current crowding, whereas only the latter and possibly localized decrease in iR drop near the insulator are relevant in a system composed of non-surface-active species. Our counterintuitive electrode design enhances electrolysis rates despite the diminished area of intimate electrolyte-electrode contact and introduces a new path for upscaling aqueous electrochemical processes.
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Affiliation(s)
- Harry Morris Rodriguez
- School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia 6102, Australia
| | - Mariusz Martyniuk
- Department of Electrical, Electronic and Computer Engineering, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Killugudi Swaminathan Iyer
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Simone Ciampi
- School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia 6102, Australia
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7
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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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8
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Zhang W, Yuan K, Zheng J, Wang X, Wang X, Song Z, Zhang L, Hu J. Effects of Nanobubbles on Photochemical Processes of Levofloxacin Photosensitizer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7021-7028. [PMID: 38501919 DOI: 10.1021/acs.langmuir.4c00041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Photodynamic therapy (PDT) stands as an efficacious modality for the treatment of cancer and various diseases, in which optimization of the electron transfer and augmentation of the production of lethal reactive oxygen species (ROS) represent pivotal challenges to enhance its therapeutic efficacy. Empirical investigations have established that the spontaneous initiation of redox reactions associated with electron transfer is feasible and is located in the gas-liquid interfaces. Meanwhile, nanobubbles (NBs) are emerging as entities capable of furnishing a plethora of such interfaces, attributed to their stability and large surface/volume ratio in bulk water. Thus, NBs provide a chance to expedite the electron-transfer kinetics within the context of PDT in an ambient environment. In this paper, we present a pioneering exploration into the impact of nitrogen nanobubbles (N2-NBs) on the electron transfer of the photosensitizer levofloxacin (LEV). Transient absorption spectra and time-resolved decay spectra, as determined through laser flash photolysis, unequivocally reveal that N2-NBs exhibit a mitigating effect on the decay of the LEV excitation triplet state, thereby facilitating subsequent processes. Of paramount significance is the observation that the presence of N2-NBs markedly accelerates the electron transfer of LEV, albeit with a marginal inhibitory influence on its energy-transfer reaction. This observation is corroborated through absorbance measurements and offers compelling evidence substantiating the role of NBs in expediting electron transfer within the ambit of PDT. The mechanism elucidated herein sheds light on how N2-NBs intricately influence both electron-transfer and energy-transfer reactions in the photosensitizer LEV. These findings not only contribute to a nuanced understanding of the underlying processes but also furnish novel insights that may inform the application of NBs in the realm of photodynamic therapy.
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Affiliation(s)
- Wenpan Zhang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaiwei Yuan
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jin Zheng
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xingya Wang
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Xiaotian Wang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhejun Song
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Lijuan Zhang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Jun Hu
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
- Xiangfu Laboratory, Jiashan 314102, China
- Institute of Materiobiology, College of Science, Shanghai University, Shanghai 200444, China
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9
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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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10
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Song X, Zare RN. The power of microdroplet photochemistry. Chem Sci 2024; 15:3670-3672. [PMID: 38454998 PMCID: PMC10915808 DOI: 10.1039/d4sc00056k] [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: 01/04/2024] [Accepted: 02/01/2024] [Indexed: 03/09/2024] Open
Abstract
This study presents compelling evidence demonstrating that irradiation of the air-solution interface, whether achieved through the spraying of microdroplets into the air or by bubbling air through a solution, significantly accelerates the rate of photochemical reactions by orders of magnitude compared to identical reaction conditions in bulk solutions. We propose this approach as a novel and versatile method for harnessing solar energy in chemical transformations.
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Affiliation(s)
- Xiaowei Song
- Department of Chemistry, Stanford University Stanford California 94305 USA
| | - Richard N Zare
- Department of Chemistry, Stanford University Stanford California 94305 USA
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11
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Song Z, Liang C, Gong K, Zhao S, Yuan X, Zhang X, Xie J. Harnessing the High Interfacial Electric Fields on Water Microdroplets to Accelerate Menshutkin Reactions. J Am Chem Soc 2023; 145:26003-26008. [PMID: 38011046 DOI: 10.1021/jacs.3c11650] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Even though it is still an emerging field, the application of a high external electric field (EEF) as a green and efficient catalyst in synthetic chemistry has recently received significant attention for the ability to deliver remarkable control of reaction selectivity and acceleration of reaction rates. Here, we extend the application of the EEF to Menshutkin reactions by taking advantage of the spontaneous high electric field at the air-water interfaces of sprayed water microdroplets. Experimentally, a series of Menshutkin reactions were accelerated by 7 orders of magnitude. Theoretically, both density functional theory calculations and ab initio molecular dynamics simulations predict that the reaction barrier decreases significantly in the presence of oriented external electric fields, thereby supporting the notion that the electric fields in the water droplets are responsible for the catalysis. In addition, the ordered solvent and reactant molecules oriented by the electric field alleviate the steric effect of solvents and increase the successful collision rates, thus facilitating faster nucleophilic attack. The success of Menshutkin reactions in this study showcases the great potential of microdroplet chemistry for 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
| | - Chiyu Liang
- 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
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, 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
| | - 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
| | - Xu Yuan
- 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
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, 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
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, 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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Song X, Basheer C, Xia Y, Li J, Abdulazeez I, Al-Saadi AA, Mofidfar M, Suliman MA, Zare RN. One-step Formation of Urea from Carbon Dioxide and Nitrogen Using Water Microdroplets. J Am Chem Soc 2023; 145:25910-25916. [PMID: 37966066 DOI: 10.1021/jacs.3c10784] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
Water (H2O) microdroplets are sprayed onto a graphite mesh covered with a CuBi2O4 coating using a 1:1 mixture of N2 and CO2 as the nebulizing gas. The resulting microdroplets contain urea [CO(NH2)2] as detected by both mass spectrometry and 13C nuclear magnetic resonance. This gas-liquid-solid heterogeneous catalytic system synthesizes urea in one step on the 0.1 ms time scale. The conversion rate reaches 2.7 mmol g-1 h-1 at 25 °C and 12.3 mmol g-1 h-1 at 65 °C, with no external voltage applied. Water microdroplets serve as the hydrogen source and the electron transfer medium for N2 and CO2 in contact with CuBi2O4. Water-gas and water-solid contact electrification are speculated to drive the reaction process. This strategy couples N2 fixation and CO2 utilization in an ecofriendly process to produce urea, converting a greenhouse gas into a value-added product.
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Affiliation(s)
- Xiaowei Song
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Chanbasha Basheer
- Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Yu Xia
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Juan Li
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Ismail Abdulazeez
- Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Abdulaziz A Al-Saadi
- Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Mohammad Mofidfar
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Mohammed Altahir Suliman
- Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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13
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Zhu C, Pham LN, Yuan X, Ouyang H, Coote ML, Zhang X. High Electric Fields on Water Microdroplets Catalyze Spontaneous and Fast Reactions in Halogen-Bond Complexes. J Am Chem Soc 2023; 145:21207-21212. [PMID: 37724917 DOI: 10.1021/jacs.3c08818] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
The use of external electric fields as green and efficient catalysts in synthetic chemistry has recently received significant attention for their ability to deliver remarkable control of reaction selectivity and acceleration of reaction rates. Technically, methods of generating high electric fields in the range of 1-10 V/nm are limited, as in-vacuo techniques have obvious scalability issues. The spontaneous high fields at various interfaces promise to solve this problem. In this study, we take advantage of the spontaneous high electric field at the air-water interface of sprayed water microdroplets in the reactions of several halogen bond systems: Nu:--X-X, where Nu: is pyridine or quinuclidine and X is bromine or iodine. The field facilitates ultrafast electron transfer from Nu:, yielding a Nu-X covalent bond and causing the X-X bond to cleave. This reaction occurs in microseconds in microdroplets but takes days to weeks in bulk solution. Density functional theory calculations predict that the reaction becomes barrier-free in the presence of oriented external electric fields, supporting the notion that the electric fields in the water droplets are responsible for the catalysis. We anticipate that microdroplet chemistry will be an avenue rich in opportunities in the reactions facilitated by high electric fields and provides an alternative way to tackle the scalability problem.
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Affiliation(s)
- 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
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Le Nhan Pham
- Institute for Nanoscale Science & Technology, Flinders University, Adelaide, South Australia 5042, Australia
| | - Xu Yuan
- 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
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Haoran Ouyang
- 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
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Michelle L Coote
- Institute for Nanoscale Science & Technology, Flinders University, Adelaide, South Australia 5042, Australia
| | - 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
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
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14
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Wang R, Ghanbari Ghalehjoughi N, Wang X. Ion-modulated interfacial fluorescence in droplet microfluidics using an ionophore-doped oil. Chem Commun (Camb) 2023; 59:11867-11870. [PMID: 37721472 DOI: 10.1039/d3cc02945j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
Fluorescence at the oil-water interface is used for chemical sensing in droplet microfluidics. Potassium ions in aqueous droplets are extracted into oil segments doped with an ionophore, a cation exchanger, and a cationic dye to expel the dye. When a low concentration of dye with a balanced solubility is used, it actively accumulates at the thin interface between oil and water instead of getting dissolved in the aqueous phase. The interfacial fluorescence is monitored distinct from the fluorescence in the oil sensor and the aqueous sample, allowing for highly sensitive and selective turn-on fluorescence sensing of ions.
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Affiliation(s)
- Renjie Wang
- Department of Chemistry, Virginia Commonwealth University, 1001 W. Main Street, Richmond, VA 23284, USA.
| | | | - Xuewei Wang
- Department of Chemistry, Virginia Commonwealth University, 1001 W. Main Street, Richmond, VA 23284, USA.
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15
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Grooms AJ, Nordmann AN, Badu-Tawiah AK. Dual Tunability for Uncatalyzed N-Alkylation of Primary Amines Enabled by Plasma-Microdroplet Fusion. Angew Chem Int Ed Engl 2023:e202311100. [PMID: 37770409 DOI: 10.1002/anie.202311100] [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: 08/01/2023] [Revised: 09/22/2023] [Accepted: 09/28/2023] [Indexed: 09/30/2023]
Abstract
The fusion of non-thermal plasma with charged microdroplets facilitates catalyst-free N-alkylation for a variety of primary amines, without halide salt biproduct generation. Significant reaction enhancement (up to >200×) is observed over microdroplet reactions generated from electrospray. This enhancement for the plasma-microdroplet system is attributed to the combined effects of energetic collisions and the presence of reactive oxygen species (ROS). The ROS (e.g., O2 ⋅- ) act as a proton sink to increase abundance of free neutral amines in the charged microdroplet environment. The effect of ROS on N-alkylation is confirmed through three unique experiments: (i) utilization of radical scavenging reagent, (ii) characterization of internal energy distribution, and (iii) controls performed without plasma, which lacked reaction acceleration. Establishing plasma discharge in the wake of charged microdroplets as a green synthetic methodology overcomes two major challenges within conventional gas-phase plasma chemistry, including the lack of selectivity and product scale-up. Both limitations are overcome here, where dual tunability is achieved by controlling reagent concentration and residence time in the microdroplet environment, affording single or double N-alkylated products. Products are readily collected yielding milligram quantities in eight hours. These results showcase a novel synthetic strategy that represents a straightforward and sustainable C-N bond-forming process.
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Affiliation(s)
- Alexander J Grooms
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH-43210, USA
| | - Anna N Nordmann
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH-43210, USA
| | - Abraham K Badu-Tawiah
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH-43210, USA
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16
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Brown JB, Qian Y, Huang-Fu ZC, Zhang T, Wang H, Rao Y. In Situ Probing of the Surface Properties of Droplets in the Air. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023. [PMID: 37497860 DOI: 10.1021/acs.langmuir.3c00875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Surface properties of nanodroplets and microdroplets are intertwined with their immense applicability in biology, medicine, production, catalysis, the environment, and the atmosphere. However, many means for analyzing droplets and their surfaces are destructive, non-interface-specific, not conducted under ambient conditions, require sample substrates, conducted ex situ, or a combination thereof. For these reasons, a technique for surface-selective in situ analyses under any condition is necessary. This feature article presents recent developments in second-order nonlinear optical scattering techniques for the in situ interfacial analysis of aerosol droplets in the air. First, we describe the abundant utilization of such droplets across industries and how their unique surface properties lead to their ubiquitous usage. Then, we describe the fundamental properties of droplets and their surfaces followed by common methods for their study. We next describe the fundamental principles of sum-frequency generation (SFG) spectroscopy, the Langmuir adsorption model, and how they are used together to describe adsorption processes at planar liquid and droplet surfaces. We also discuss the history of developments of second-order scattering from droplets suspended in dispersive media and introduce second-harmonic scattering (SHS) and sum-frequency scattering (SFS) spectroscopies. We then go on to outline the developments of SHS, electronic sum-frequency scattering (ESFS), and vibrational sum-frequency scattering (VSFS) from droplets in the air and discuss the fundamental insights about droplet surfaces that the techniques have provided. Finally, we describe some of the areas of nonlinear scattering from airborne droplets which need improvement as well as potential future directions and utilizations of SHS, ESFS, and VSFS throughout environmental systems, interfacial chemistry, and fundamental physics. The goal of this feature article is to spread knowledge about droplets and their unique surface properties as well as introduce second-order nonlinear scattering to a broad audience who may be unaware of recent progress and advancements in their applicability.
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Affiliation(s)
- Jesse B Brown
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
| | - Yuqin Qian
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
| | - Zhi-Chao Huang-Fu
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
| | - Tong Zhang
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
- Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Hui Wang
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
| | - Yi Rao
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
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17
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Jin S, Chen H, Yuan X, Xing D, Wang R, Zhao L, Zhang D, Gong C, Zhu C, Gao X, Chen Y, Zhang X. The Spontaneous Electron-Mediated Redox Processes on Sprayed Water Microdroplets. JACS AU 2023; 3:1563-1571. [PMID: 37388681 PMCID: PMC10301804 DOI: 10.1021/jacsau.3c00191] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/11/2023] [Accepted: 05/18/2023] [Indexed: 07/01/2023]
Abstract
Water is considered as an inert environment for the dispersion of many chemical systems. However, by simply spraying bulk water into microsized droplets, the water microdroplets have been shown to possess a large plethora of unique properties, including the ability to accelerate chemical reactions by several orders of magnitude compared to the same reactions in bulk water, and/or to trigger spontaneous reactions that cannot occur in bulk water. A high electric field (∼109 V/m) at the air-water interface of microdroplets has been postulated to be the probable cause of the unique chemistries. This high field can even oxidize electrons out of hydroxide ions or other closed-shell molecules dissolved in water, forming radicals and electrons. Subsequently, the electrons can trigger further reduction processes. In this Perspective, by showing a large number of such electron-mediated redox reactions, and by studying the kinetics of these reactions, we opine that the redox reactions on sprayed water microdroplets are essentially processes using electrons as the charge carriers. The potential impacts of the redox capability of microdroplets are also discussed in a larger context of synthetic chemistry and atmospheric chemistry.
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Affiliation(s)
- Shuihui Jin
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Huan Chen
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Xu Yuan
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Dong Xing
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Lingling Zhao
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Dongmei 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Chu Gong
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Xufeng Gao
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
| | - Yeye Chen
- 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, 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
- Haihe
Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China
- Beijing
National Laboratory for Molecular Sciences, Beijing, 100190, China
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18
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Voci S, Dick JE. An electrochemical perspective on the interfacial width between two immiscible liquid phases. CURRENT OPINION IN ELECTROCHEMISTRY 2023; 39:101244. [PMID: 37538354 PMCID: PMC10399975 DOI: 10.1016/j.coelec.2023.101244] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/04/2023]
Abstract
Molecular dynamics simulations and vibrational sum-frequency spectroscopy are historically the main techniques applied to the description of the molecular structure and dynamics of the immiscible liquid/liquid interface. A molecular sharpness is estimated for oil/water interfaces, with an interfacial width that extends from hundreds of Å to 1 nm. However, electrochemical studies have elucidated a deeper liquid/liquid interface on the order of several micrometers. The breaking down of single-entity electrochemistry to simpler systems and the combination of high-resolution microscopies is confirming a larger extension of the interface. What can be the role of the electrochemist in clarifying this fundamental question? We try to give a suggestion at the end of a brief historical overview of the liquid/liquid interface studies.
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19
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Bittermann MR, Morozova TI, Velandia SF, Mirzahossein E, Deblais A, Woutersen S, Bonn D. Surface-Mediated Molecular Transport of a Lipophilic Fluorescent Probe in Polydisperse Oil-in-Water Emulsions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:4207-4215. [PMID: 36919825 PMCID: PMC10061922 DOI: 10.1021/acs.langmuir.2c02597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/07/2023] [Indexed: 06/18/2023]
Abstract
Emulsions often act as carriers for water-insoluble solutes that are delivered to a specific target. The molecular transport of solutes in emulsions can be facilitated by surfactants and is often limited by diffusion through the continuous phase. We here investigate this transport on a molecular scale by using a lipophilic molecular rotor as a proxy for solutes. Using fluorescence lifetime microscopy we track the transport of these molecules from the continuous phase toward the dispersed phase in polydisperse oil-in-water emulsions. We show that this transport comprises two time scales, which vary significantly with droplet size and surfactant concentration, and, depending on the type of surfactant used, can be limited either by transport across the oil-water interface or by diffusion through the continuous phase. By studying the time-resolved fluorescence of the fluorophore, accompanied by molecular dynamics simulations, we demonstrate how the rate of transport observed on a macroscopic scale can be explained in terms of the local environment that the probe molecules are exposed to.
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Affiliation(s)
- Marius R. Bittermann
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | | | - Santiago F. Velandia
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Elham Mirzahossein
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Antoine Deblais
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Sander Woutersen
- Van
’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Daniel Bonn
- Van
der Waals-Zeeman Institute, IoP, University
of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
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20
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Rafferty A, Vennes B, Bain A, Preston TC. Optical trapping and light scattering in atmospheric aerosol science. Phys Chem Chem Phys 2023; 25:7066-7089. [PMID: 36852581 DOI: 10.1039/d2cp05301b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Aerosol particles are ubiquitous in the atmosphere, and currently contribute a large uncertainty to climate models. Part of the endeavour to reduce this uncertainty takes the form of improving our understanding of aerosol at the microphysical level, thus enabling chemical and physical processes to be more accurately represented in larger scale models. In addition to modeling efforts, there is a need to develop new instruments and methodologies to interrogate the physicochemical properties of aerosol. This perspective presents the development, theory, and application of optical trapping, a powerful tool for single particle investigations of aerosol. After providing an overview of the role of aerosol in Earth's atmosphere and the microphysics of these particles, we present a brief history of optical trapping and a more detailed look at its application to aerosol particles. We also compare optical trapping to other single particle techniques. Understanding the interaction of light with single particles is essential for interpreting experimental measurements. In the final part of this perspective, we provide the relevant formalism for understanding both elastic and inelastic light scattering for single particles. The developments discussed here go beyond Mie theory and include both how particle and beam shape affect spectra. Throughout the entirety of this work, we highlight numerous references and examples, mostly from the last decade, of the application of optical trapping to systems that are relevant to the atmospheric aerosol.
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Affiliation(s)
| | - Benjamin Vennes
- Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, Canada.
| | - Alison Bain
- School of Chemistry, University of Bristol, Bristol, UK
| | - Thomas C Preston
- Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, Canada. .,Department of Chemistry, McGill University, Montreal, Quebec, Canada
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21
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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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22
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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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23
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Zhang D, Yuan X, Gong C, Zhang X. High Electric Field on Water Microdroplets Catalyzes Spontaneous and Ultrafast Oxidative C-H/N-H Cross-Coupling. J Am Chem Soc 2022; 144:16184-16190. [PMID: 35960958 DOI: 10.1021/jacs.2c07385] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Oxidative C-H/N-H cross-coupling has emerged as an atom-economical method for the construction of C-N bonds. Conventional oxidative C-H/N-H coupling requires at least one of the following: high temperatures, strong oxidizers, transition metal catalysts, organic solvents, light, and electrochemical cells. In this study, by merely spraying the water solutions of the substrates into microdroplets at room temperature, we show a series of oxidative C-H/N-H coupling products that are strikingly produced in a spontaneous and ultrafast manner. The reactions are accelerated by six orders of magnitude compared to the same reactions in the bulk. It has been previously proposed by fluorescence microscopy and theory that the spontaneously generated electric field at the microdroplets peripheries can be in the ∼109 V/m range. Based on mass spectrometric analysis of key radical intermediates, we opine that the ultrahigh electric field catalytically oxidizes the substrates by removing an electron, which further promotes C/N coupling. Taken together, we anticipate that microdroplet chemistry will be an avenue rich in green opportunities of constructing C-heteroatom bonds.
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Affiliation(s)
- Dongmei Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Shenzhen Research Institute, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Xu Yuan
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Shenzhen Research Institute, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Chu Gong
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Shenzhen Research Institute, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Shenzhen Research Institute, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China.,Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China.,Beijing National Laboratory for Molecular Sciences, Beijing 100190, China
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24
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Ai Y, Xu J, Gunawardena HP, Zare RN, Chen H. Investigation of Tryptic Protein Digestion in Microdroplets and in Bulk Solution. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:1238-1249. [PMID: 35647885 PMCID: PMC10512443 DOI: 10.1021/jasms.2c00072] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Recent studies have shown that ultrafast enzymatic digestion of proteins can be achieved in microdroplet within 250 μs. Further investigation of peptides resulting from microdroplet digestion (MD) would be necessary to evaluate it as an alternative to the conventional bulk digestion for bottom-up and biotherapeutic protein characterization. Herein we examined and compared protein tryptic digestion in both MD and bulk solution. In the case of MD of β-lactoglobulin B, the preservation of long peptides was observed due to the short digestion time. In addition, MD is applicable to digest both high- and low-abundance proteins in mixture. In the case of digesting NIST 8671 mAb antibody containing a low level of commonly encountered host cell protein (HCP) PLBL2 (mAb:PLBL2 = 100:1 by weight), MD produced lower levels of digestion-induced chemical modifications of asparagine/glutamine deamidation, compared with overnight digestion. No significant difference between MD and bulk digestion was observed in terms of trypsin digestion specificity based on examination of semi- and unspecific-cleaved peptides. Our study suggests that MD, a fast digestion approach, could be adopted for bottom-up proteomics research and for peptide mapping of mAbs to characterize site-specific deamidation and glycosylation, for the purpose of development of biopharmaceuticals.
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Affiliation(s)
- Yongling Ai
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, USA
| | - Jeffrey Xu
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, USA
| | - Harsha P. Gunawardena
- Janssen Research & Development, The Janssen Pharmaceutical Companies of Johnson & Johnson, Spring House, Pennsylvania 19477, USA
| | - Richard N. Zare
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA
| | - Hao Chen
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, USA
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25
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Qiu L, Morato NM, Huang KH, Cooks RG. Spontaneous Water Radical Cation Oxidation at Double Bonds in Microdroplets. Front Chem 2022; 10:903774. [PMID: 35559217 PMCID: PMC9086510 DOI: 10.3389/fchem.2022.903774] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 04/11/2022] [Indexed: 12/20/2022] Open
Abstract
Spontaneous oxidation of compounds containing diverse X=Y moieties (e.g., sulfonamides, ketones, esters, sulfones) occurs readily in organic-solvent microdroplets. This surprising phenomenon is proposed to be driven by the generation of an intermediate species [M+H2O]+·: a covalent adduct of water radical cation (H2O+·) with the reactant molecule (M). The adduct is observed in the positive ion mass spectrum while its formation in the interfacial region of the microdroplet (i.e., at the air-droplet interface) is indicated by the strong dependence of the oxidation product formation on the spray distance (which reflects the droplet size and consequently the surface-to-volume ratio) and the solvent composition. Importantly, based on the screening of a ca. 21,000-compound library and the detailed consideration of six functional groups, the formation of a molecular adduct with the water radical cation is a significant route to ionization in positive ion mode electrospray, where it is favored in those compounds with X=Y moieties which lack basic groups. A set of model monofunctional systems was studied and in one case, benzyl benzoate, evidence was found for oxidation driven by hydroxyl radical adduct formation followed by protonation in addition to the dominant water radical cation addition process. Significant implications of molecular ionization by water radical cations for oxidation processes in atmospheric aerosols, analytical mass spectrometry and small-scale synthesis are noted.
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26
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Xia Y, Li J, Huang LX, Hua B, Guo SS. In Situ Microreaction Platform Based on Acoustic Droplet Manipulation for Ultra-High-Precision Multiplex Bioassay. Anal Chem 2022; 94:6347-6354. [DOI: 10.1021/acs.analchem.2c00698] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yu Xia
- Key Laboratory of Artificial Micro/Nano-Structures, Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Juan Li
- Key Laboratory of Artificial Micro/Nano-Structures, Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Lan-Xiang Huang
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University Wuhan 430072, China
| | - Bo Hua
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430072, China
| | - Shi-Shang Guo
- Key Laboratory of Artificial Micro/Nano-Structures, Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
- Hubei Yangtze Memory Laboratories, Wuhan 430072, China
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27
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Gong C, Li D, Li X, Zhang D, Xing D, Zhao L, Yuan X, Zhang X. Spontaneous Reduction-Induced Degradation of Viologen Compounds in Water Microdroplets and Its Inhibition by Host-Guest Complexation. J Am Chem Soc 2022; 144:3510-3516. [PMID: 35167288 DOI: 10.1021/jacs.1c12028] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Water serves as an inert environment for the dispersion and application of many kinds of herbicides. Viologen compounds, a type of widely used but highly toxic herbicide, are stable in bulk water, whose half-life can be up to 23 weeks in natural water, imposing a severe health risk to mammals. In this study, we present the striking results of the spontaneous and ultrafast reduction-induced degradation of three viologen compounds in water microdroplets and provide the concentration, time, temperature dependence, mechanism, and scale-up of the reactions. We postulate that the electrons existing at the air-water interface of the microdroplets due to the unique redox potential therein initiate the reduction, from which further degradation occurs. The host-guest complexation between cucurbit[7]uril and viologens only slightly changes the redox potential of viologens in the bulk but completely inhibits the reactions in microdroplets, adding to the uniqueness of the redox potentials at the air-water interfaces of microdroplets. Taken together, microdroplets might have been functioning as naturally occurring ubiquitous tiny electrochemical cells for a plethora of unique redox reactions that were thought to be impossible in the bulk water.
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Affiliation(s)
- Chu Gong
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
| | - Danyang Li
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
| | - Xilai Li
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
| | - Dongmei Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
| | - Dong Xing
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
| | - Lingling Zhao
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
| | - Xu Yuan
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Haihe Laboratory of Sustainable Chemical Transformations, Beijing National Laboratory for Molecular Sciences, Frontiers Science Center for New Organic Matter, Shenzhen Research Institute, Nankai University, Tianjin 300071, China
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28
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Droplet Flow Assisted Electrocatalytic Oxidation of Selected Alcohols under Ambient Condition. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27020382. [PMID: 35056693 PMCID: PMC8779358 DOI: 10.3390/molecules27020382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/27/2021] [Accepted: 01/04/2022] [Indexed: 12/04/2022]
Abstract
This study reports using a droplet flow assisted mechanism to enhance the electrocatalytic oxidation of benzyl alcohol, 2-phenoxyethanol, and hydroxymethylfurfural at room temperature. Cobalt phosphide (CoP) was employed as an active electrocatalyst to promote the oxidation of each of the individual substrates. Surface analysis of the CoP electrocatalyst using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), as well as electrochemical characterization, revealed that it had excellent catalytic activity for each of the substrates studied. The combined droplet flow with the continuous flow electrochemical oxidation approach significantly enhanced the conversion and selectivity of the transformation reactions. The results of this investigation show that at an electrolysis potential of 1.3 V and ambient conditions, both the selectivity and yield of aldehyde from substrate conversion can reach 97.0%.
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29
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Rainer T, Eidelpes R, Tollinger M, Müller T. Microdroplet Mass Spectrometry Enables Extremely Accelerated Pepsin Digestion of Proteins. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1841-1845. [PMID: 34101451 PMCID: PMC8267842 DOI: 10.1021/jasms.1c00126] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In microdroplets, rates of chemical or biomolecular reactions can exceed those in the bulk phase by more than a million times. As electrospray ionization-based mass spectrometry (MS) involves the formation of charged microdroplets, reaction acceleration and online MS monitoring of reaction products can readily be performed at the same time. We investigated accelerated enzymatic reactions in microdroplets and focused on the proteolytic enzyme pepsin. Electrosonic spray ionization (ESSI) was utilized for developing the ultrarapid pepsin in-spray digestion of two different proteins, cytochrome c and RocC, at low pH values. The optimization of the protein digestion aimed at achieving maximum sequence coverage for the analyzed proteins. Furthermore, carefully designed control experiments allowed us to unambiguously prove that enzymatic protein cleavage almost exclusively occurs within the spray at a millisecond time scale and not prior to microdroplet generation.
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30
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Ultrafast enzymatic digestion of deoxyribonucleic acid in aqueous microdroplets for sequence discrimination and identification. QRB DISCOVERY 2021; 2:e4. [PMID: 34192264 PMCID: PMC8185430 DOI: 10.1017/qrd.2021.2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 04/05/2021] [Accepted: 05/07/2021] [Indexed: 12/31/2022] Open
Abstract
We report the use of aqueous microdroplets to accelerate deoxyribonucleic acid (DNA) fragmentation by deoxyribonuclease I (DNase I), and we present a simple, ultrafast approach named DNA fragment mass fingerprinting to discriminate different DNA sequences by comparing their fragment mass patterns. DNA fragmentation in tiny microdroplets, which was produced by electrosonically spraying (+3 kV) a room temperature aqueous solution containing 10 μM DNA and 10 μg ml−1 DNase I from a homemade setup, takes less than 1 ms. High differentiation/identification fidelity could be obtained by applying a cosine correlation measure for similarity assessment between two fragment mass patterns, which compares both mass-to-charge ratios (m/z) with an error tolerance of 5 ppm and the peaks’ relative intensities. A single-nucleotide mutation in the sequence of bases, as exemplified by the sickle cell anemia mutation, is differentiated by setting a cutoff value of similarity at 90%. The order change of two adjacent bases in the sequence could still be well discriminated with a similarity of only 62% between the fragment mass patterns of the two similar sequences, which have the same molecular weights and thus cannot be differentiated by gel electrophoresis or direct mass detection by mass spectrometry. Compared to traditional genotyping methods, such as quantitative real-time polymerase chain reaction, the identification process with our approach could be completed within several minutes without any other expensive and complicated reagents or experimental steps. The potential of our approach for convenient and fast microbe genetic discrimination or identification is further demonstrated by differentiating the Orf1ab gene fragments of two similar coronaviruses with a very high sequence homologous rate of 96%, SARS-CoV-2 and bat-SL-CoVZC45, with a similarity of 0% between their fragment mass patterns.
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31
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Kuai D, Cheng H, Kuan KY, Yan X. Accelerated five-component spiro-pyrrolidine construction at the air-liquid interface. Chem Commun (Camb) 2021; 57:3757-3760. [PMID: 33876122 DOI: 10.1039/d1cc00574j] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Multi-component reactions assemble complex molecules in a highly effective way, however, they often suffer from long reaction times. We demonstrate that acceleration of a five-component spiro-pyrrolidine construction can be achieved in microdroplets and thin films. The deposition method and mild heating are crucial factors for product formation. Three key intermediates were captured by mass spectrometry to elucidate the tandem reaction mechanism. We also found that hydrogen bonding can significantly flatten the energy barrier at the air-liquid interface.
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Affiliation(s)
- Dacheng Kuai
- Department of Chemistry, Texas A&M University, College Station, TX 77843, USA.
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32
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Li Y, Mehari TF, Wei Z, Liu Y, Cooks RG. Reaction acceleration at air-solution interfaces: Anisotropic rate constants for Katritzky transamination. JOURNAL OF MASS SPECTROMETRY : JMS 2021; 56:e4585. [PMID: 32686310 DOI: 10.1002/jms.4585] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 05/22/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
To disentangle the factors controlling the rates of accelerated reactions in droplets, we used mass spectrometry to study the Katritzky transamination in levitated Leidenfrost droplets of different yet constant volumes over a range of concentrations while holding concentration constant by adding back the evaporated solvent. The set of concentration and droplet volume data indicates that the reaction rate in the surface region is much higher than that in the interior. These same effects of concentration and volume were also seen in bulk solutions. Three pyrylium reagents with different surface activity showed differences in transamination reactivity. The conclusion is drawn that reactions with surface-active reactants are subject to greater acceleration, as seen particularly at lower concentrations in systems of higher surface-to-volume ratios. These results highlight the key role that air-solution interfaces play in Katritzky reaction acceleration. They are also consistent with the view that reaction-increased rate constant is at least in part due to limited solvation of reagents at the interface.
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Affiliation(s)
- Yangjie Li
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
| | - Tsdale F Mehari
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
| | - Zhenwei Wei
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
| | - Yong Liu
- Department of Analytical Sciences, MRL, Merck & Co., Inc., Rahway, New Jersey, USA
| | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
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33
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Zhao P, Gunawardena HP, Zhong X, Zare RN, Chen H. Microdroplet Ultrafast Reactions Speed Antibody Characterization. Anal Chem 2021; 93:3997-4005. [PMID: 33590747 DOI: 10.1021/acs.analchem.0c04974] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recently, microdroplet reactions have aroused much interest because the microdroplet provides a unique medium where organic reactions could be accelerated by a factor of 103 or more. However, microdroplet reactions of proteins have been rarely studied. We report the occurrence of multiple-step reactions of a large protein, specifically, the digestion, reduction, and deglycosylation of an intact antibody, which can take place in microseconds with high reaction yields in aqueous microdroplets at room temperature. As a result, fast structural characterization of a monoclonal antibody, essential for assessing its quality as a therapeutic drug, can be enabled. We found that the IgG1 antibody can be digested completely by the IdeS protease in aqueous microdroplets in 250 microseconds, a 7.5 million-fold improvement in speed in comparison to traditional digestion in bulk solution (>30 min). Strikingly, inclusion of the reductant tris(2-carboxyethyl)phosphine in the spray solution caused simultaneous antibody digestion and disulfide bond reduction. Digested and reduced antibody fragments were either collected or analyzed online by mass spectrometry. Further addition of PNGase F glycosylase into the spray solution led to antibody deglycosylation, thereby producing reduced and deglycosylated fragments of analytical importance. In addition, glycated fragments of IgG1 derived from glucose modification were identified rapidly with this ultrafast digestion/reduction technique. We suggest that microdroplets can serve as powerful microreactors for both exploring large-molecule reactions and speeding their structural analyses.
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Affiliation(s)
- Pengyi Zhao
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Harsha P Gunawardena
- Janssen Research & Development, The Janssen Pharmaceutical Companies of Johnson & Johnson, Spring House, Pennsylvania 19477, United States
| | - Xiaoqin Zhong
- Department of Chemistry, Fudan University, Shanghai 200438, China
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, United States
| | - Hao Chen
- Department of Chemistry & Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
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34
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Li Y, Mehari TF, Wei Z, Liu Y, Cooks RG. Reaction Acceleration at Solid/Solution Interfaces: Katritzky Reaction Catalyzed by Glass Particles. Angew Chem Int Ed Engl 2021; 60:2929-2933. [PMID: 33164315 DOI: 10.1002/anie.202014613] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Indexed: 11/08/2022]
Abstract
The Katritzky reaction in bulk solution at room temperature is accelerated significantly by the surface of a glass container compared to a plastic container. Remarkably, the reaction rate is increased by more than two orders of magnitude upon the addition of glass particles with the rate increasing linearly with increasing amounts of glass. A similar phenomenon is observed when glass particles are added to levitated droplets, where large acceleration factors are seen. Evidence shows that glass acts as a "green" heterogeneous catalyst: it participates as a base in the deprotonation step and is recovered unchanged from the reaction mixture. Reaction acceleration at two separate interfaces is recognized in this study: i) air/solution phase acceleration, as is well known in microdroplets; ii) solid/solution phase, where such acceleration appears to be a new phenomenon.
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Affiliation(s)
- Yangjie Li
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907, USA
| | - Tsdale F Mehari
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907, USA
| | - Zhenwei Wei
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907, USA
| | - Yong Liu
- Department of Analytical Sciences, MRL, Merck & Co., Inc., 126 East Lincoln Ave, Rahway, NJ, 07065, USA
| | - R Graham Cooks
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907, USA
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35
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Reaction Acceleration at Solid/Solution Interfaces: Katritzky Reaction Catalyzed by Glass Particles. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014613] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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36
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Resonance in Chirogenesis and Photochirogenesis: Colloidal Polymers Meet Chiral Optofluidics. Symmetry (Basel) 2021. [DOI: 10.3390/sym13020199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Metastable colloids made of crystalline and/or non-crystalline matters render abilities of photonic resonators susceptible to chiral chemical and circularly polarized light sources. By assuming that μm-size colloids and co-colloids consisting of π- and/or σ-conjugated polymers dispersed into an optofluidic medium are artificial models of open-flow, non-equilibrium coacervates, we showcase experimentally resonance effects in chirogenesis and photochirogenesis, revealed by gigantic boosted chiroptical signals as circular dichroism (CD), optical rotation dispersion, circularly polarized luminescence (CPL), and CPL excitation (CPLE) spectral datasets. The resonance in chirogenesis occurs at very specific refractive indices (RIs) of the surrounding medium. The chirogenesis is susceptible to the nature of the optically active optofluidic medium. Moreover, upon an excitation-wavelength-dependent circularly polarized (CP) light source, a fully controlled absolute photochirogenesis, which includes all chiroptical generation, inversion, erase, switching, and short-/long-lived memories, is possible when the colloidal non-photochromic and photochromic polymers are dispersed in an achiral optofluidic medium with a tuned RI. The hand of the CP light source is not a determining factor for the product chirality. These results are associated with my experience concerning amphiphilic polymerizable colloids, in which, four decades ago, allowed proposing a perspective that colloids are connectable to light, polymers, helix, coacervates, and panspermia hypotheses, nuclear physics, biology, radioisotopes, homochirality question, first life, and cosmology.
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37
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Huang KH, Wei Z, Cooks RG. Accelerated reactions of amines with carbon dioxide driven by superacid at the microdroplet interface. Chem Sci 2020; 12:2242-2250. [PMID: 34163990 PMCID: PMC8179320 DOI: 10.1039/d0sc05625a] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Microdroplets display distinctive interfacial chemistry, manifested as accelerated reactions relative to those observed for the same reagents in bulk. Carbon dioxide undergoes C–N bond formation reactions with amines at the interface of droplets to form carbamic acids. Electrospray ionization mass spectrometry displays the reaction products in the form of the protonated and deprotonated carbamic acid. Electrosonic spray ionization (ESSI) utilizing carbon dioxide as nebulization gas, confines reaction to the gas–liquid interface where it proceeds much faster than in the bulk. Intriguingly, trace amounts of water accelerate the reaction, presumably by formation of superacid or superbase at the water interface. The suggested mechanism of protonation of CO2 followed by nucleophilic attack by the amine is analogous to that previously advanced for imidazole formation from carboxylic acids and diamines. Microdroplets display distinctive interfacial chemistry, manifested as accelerated reactions relative to those observed for the same reagents in bulk.![]()
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Affiliation(s)
- Kai-Hung Huang
- Department of Chemistry, Purdue University West Lafayette IN 47907 USA
| | - Zhenwei Wei
- Department of Chemistry, Purdue University West Lafayette IN 47907 USA
| | - R Graham Cooks
- Department of Chemistry, Purdue University West Lafayette IN 47907 USA
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38
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Lee JK, Han HS, Chaikasetsin S, Marron DP, Waymouth RM, Prinz FB, Zare RN. Condensing water vapor to droplets generates hydrogen peroxide. Proc Natl Acad Sci U S A 2020; 117:30934-30941. [PMID: 33229543 PMCID: PMC7733789 DOI: 10.1073/pnas.2020158117] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
It was previously shown [J. K. Lee et al., Proc. Natl. Acad. Sci. U.S.A, 116, 19294-19298 (2019)] that hydrogen peroxide (H2O2) is spontaneously produced in micrometer-sized water droplets (microdroplets), which are generated by atomizing bulk water using nebulization without the application of an external electric field. Here we report that H2O2 is spontaneously produced in water microdroplets formed by dropwise condensation of water vapor on low-temperature substrates. Because peroxide formation is induced by a strong electric field formed at the water-air interface of microdroplets, no catalysts or external electrical bias, as well as precursor chemicals, are necessary. Time-course observations of the H2O2 production in condensate microdroplets showed that H2O2 was generated from microdroplets with sizes typically less than ∼10 µm. The spontaneous production of H2O2 was commonly observed on various different substrates, including silicon, plastic, glass, and metal. Studies with substrates with different surface conditions showed that the nucleation and the growth processes of condensate water microdroplets govern H2O2 generation. We also found that the H2O2 production yield strongly depends on environmental conditions, including relative humidity and substrate temperature. These results show that the production of H2O2 occurs in water microdroplets formed by not only atomizing bulk water but also condensing water vapor, suggesting that spontaneous water oxidation to form H2O2 from water microdroplets is a general phenomenon. These findings provide innovative opportunities for green chemistry at heterogeneous interfaces, self-cleaning of surfaces, and safe and effective disinfection. They also may have important implications for prebiotic chemistry.
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Affiliation(s)
- Jae Kyoo Lee
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - Hyun Soo Han
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305
- Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305
| | | | - Daniel P Marron
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | | | - Fritz B Prinz
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305;
- Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, CA 94305;
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39
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Xiong H, Lee JK, Zare RN, Min W. Strong Concentration Enhancement of Molecules at the Interface of Aqueous Microdroplets. J Phys Chem B 2020; 124:9938-9944. [DOI: 10.1021/acs.jpcb.0c07718] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hanqing Xiong
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Jae Kyoo Lee
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Richard N. Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Wei Min
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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40
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Wei Z, Li Y, Cooks RG, Yan X. Accelerated Reaction Kinetics in Microdroplets: Overview and Recent Developments. Annu Rev Phys Chem 2020; 71:31-51. [PMID: 32312193 DOI: 10.1146/annurev-physchem-121319-110654] [Citation(s) in RCA: 218] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Various organic reactions, including important synthetic reactions involving C-C, C-N, and C-O bond formation as well as reactions of biomolecules, are accelerated when the reagents are present in sprayed or levitated microdroplets or in thin films. The reaction rates increase by orders of magnitude with decreasing droplet size or film thickness. The effect is associated with reactions at the solution-air interface. A key factor is partial solvation of the reagents at the interface, which reduces the critical energy for reaction. This phenomenon is of intrinsic interest and potentially of practical value as a simple, rapid method of performing small-scale synthesis.
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Affiliation(s)
- Zhenwei Wei
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA;
| | - Yangjie Li
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA;
| | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA;
| | - Xin Yan
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA;
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41
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Kang J, Lhee S, Lee JK, Zare RN, Nam HG. Restricted intramolecular rotation of fluorescent molecular rotors at the periphery of aqueous microdroplets in oil. Sci Rep 2020; 10:16859. [PMID: 33033365 PMCID: PMC7545199 DOI: 10.1038/s41598-020-73980-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 08/17/2020] [Indexed: 01/14/2023] Open
Abstract
Fluorescent molecular rotor dyes, including Cy3, Cy5, and Alexa Fluor 555, dissolved in micron-sized aqueous droplets (microdroplets) in oil were excited, and the fluorescence intensity was recorded as function of time. We observed lengthening of the fluorescence lifetime of these dyes at the water-oil periphery, which extended several microns inward. This behavior shows that intramolecular rotation is restricted at and near the microdroplet interface. Lengthened lifetimes were observed in water microdroplets but not in microdroplets composed of organic solvents. This lifetime change was relatively insensitive to added glycerol up to 60%, suggesting that solution viscosity is not the dominant mechanism. These restricted intramolecular rotations at and near the microdroplet periphery are consistent with the reduced entropy observed in chemical reactions in microdroplets compared to the same reaction conditions in bulk solution and helps us further understand why microdroplet chemistry differs so markedly from bulk-phase chemistry.
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Affiliation(s)
- Jooyoun Kang
- Center for Plant Aging Research, Institute for Basic Science, Daegu, 42988, Republic of Korea.,Department of Chemistry, Stanford University, Stanford, CA, 94305, USA
| | - SangMoon Lhee
- Center for Plant Aging Research, Institute for Basic Science, Daegu, 42988, Republic of Korea
| | - Jae Kyoo Lee
- Department of Chemistry, Stanford University, Stanford, CA, 94305, USA
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, CA, 94305, USA.
| | - Hong Gil Nam
- Center for Plant Aging Research, Institute for Basic Science, Daegu, 42988, Republic of Korea. .,Department of New Biology, DGIST, Daegu, 42988, Republic of Korea.
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42
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Lhee S, Lee JK, Kang J, Kato S, Kim S, Zare RN, Nam HG. Spatial localization of charged molecules by salt ions in oil-confined water microdroplets. SCIENCE ADVANCES 2020; 6:6/41/eaba0181. [PMID: 33028513 PMCID: PMC7541078 DOI: 10.1126/sciadv.aba0181] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 08/19/2020] [Indexed: 05/28/2023]
Abstract
Cells contain more than 100 mM salt ions that are typically confined to dimensions of 5 to 10 micrometers by a hydrophobic cellular membrane. We found that in aqueous microdroplets having the same size as cells and that are confined in hydrocarbon oil, negatively charged molecules were distributed rather uniformly over the interior of the microdroplet, whereas positively charged molecules were localized at and near the surface. However, the addition of salt (NaCl) to the microdroplet caused all charged molecules to be localized near the oil-water interface. This salt-induced relocalization required less salt concentration in microdroplets compared to bulk water. Moreover, the localization became more prominent as the size of the microdroplet was reduced. The relocatization also critically depended on the type of oil. Our results imply that salt ions and different hydrophobic interfaces together may govern the local distribution of charged biomolecules in confined intracellular environments.
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Affiliation(s)
- SangMoon Lhee
- Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea
| | - Jae Kyoo Lee
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Jooyoun Kang
- Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Shota Kato
- Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea
| | - Sunhee Kim
- Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA.
| | - Hong Gil Nam
- Center for Plant Aging Research, Institute for Basic Science, Daegu 42988, Republic of Korea.
- Department of New Biology, DGIST, Daegu 42988, Republic of Korea
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43
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Xiong H, Lee JK, Zare RN, Min W. Strong Electric Field Observed at the Interface of Aqueous Microdroplets. J Phys Chem Lett 2020; 11:7423-7428. [PMID: 32804510 DOI: 10.1021/acs.jpclett.0c02061] [Citation(s) in RCA: 140] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Chemical reactions in aqueous microdroplets often exhibit unusual kinetic and thermodynamic properties not observed in bulk solution. While an electric field has been implicated at the water interface, there has been no direct measurement in aqueous microdroplets, largely due to the lack of proper measurement tools. Herein, we employ newly developed stimulated Raman excited fluorescence microscopy to measure the electric field at the water-oil interface of microdroplets. As determined by the vibrational Stark effect of a nitrile-bearing fluorescent probe, the strength of the electric field is found to be on the order of 107 V/cm. This strong electric field aligns probe dipoles with respect to the interface. The formation of the electric field likely arises from charge separation caused by the adsorption of negative ions at the water-oil interface of microdroplets. We suggest that this strong electric field might account in part for the unique properties of chemical reactions reported in microdroplets.
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Affiliation(s)
- Hanqing Xiong
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Jae Kyoo Lee
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Wei Min
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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44
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Wilson KR, Prophet AM, Rovelli G, Willis MD, Rapf RJ, Jacobs MI. A kinetic description of how interfaces accelerate reactions in micro-compartments. Chem Sci 2020; 11:8533-8545. [PMID: 34123113 PMCID: PMC8163377 DOI: 10.1039/d0sc03189e] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A kinetic expression is derived to explain how interfaces alter bulk chemical equilibria and accelerate reactions in micro-compartments. This description, aided by the development of a stochastic model, quantitatively predicts previous experimental observations of accelerated imine synthesis in micron-sized emulsions. The expression accounts for how reactant concentration and compartment size together lead to accelerated reaction rates under micro-confinement. These rates do not depend solely on concentration, but rather the fraction of total molecules in the compartment that are at the interface. Although there are ∼107 to 1013 solute molecules in a typical micro-compartment, a kind of "stochasticity" appears when compartment size and reagent concentration yield nearly equal numbers of bulk and interfacial molecules. Although this is distinct from the stochasticity produced by nano-confinement, these results show how interfaces can govern chemical transformations in larger atmospheric, geologic and biological compartments.
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Affiliation(s)
- Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Alexander M Prophet
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA .,Department of Chemistry, University of California Berkeley CA 94720 USA
| | - Grazia Rovelli
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Megan D Willis
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Rebecca J Rapf
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Michael I Jacobs
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
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45
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Narendra N, Chen X, Wang J, Charles J, Cooks RG, Kubis T. Quantum Mechanical Modeling of Reaction Rate Acceleration in Microdroplets. J Phys Chem A 2020; 124:4984-4989. [PMID: 32453564 DOI: 10.1021/acs.jpca.0c03225] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Organic reactions in microdroplets can be orders of magnitude faster than their bulk counterparts. We hypothesize that solvation energy differences between bulk and interface play a key role in the intrinsic rate constant increase and test the hypothesis with explicit solvent calculations. We demonstrate for both the protonated phenylhydrazine reagent and the hydrazone transition state (TSB) that molecular orientations which place the charge sites at the surface confer high energy. A pathway in which this high-energy form transforms into a fully solvated TSB has a lower activation energy than bulk by some 59 kJ/mol, a result that is consistent with experimental rate acceleration studies.
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Affiliation(s)
- Namita Narendra
- Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47906, United States
| | - Xingshuo Chen
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, United States
| | - Jinying Wang
- Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47906, United States
| | - James Charles
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906, United States
| | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, United States
| | - Tillmann Kubis
- Network for Computational Nanotechnology, Purdue University, West Lafayette, Indiana 47906, United States.,School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906, United States.,Center for Predictive Materials and Devices, Purdue University, West Lafayette, Indiana 47906, United States.,Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, Indiana 47906, United States
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46
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Water-in-oil microcompartments for the study of biomimetic drug metabolism. J Colloid Interface Sci 2020; 569:378-385. [PMID: 32126350 DOI: 10.1016/j.jcis.2020.02.096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 02/19/2020] [Accepted: 02/24/2020] [Indexed: 12/24/2022]
Abstract
Microcompartments in the form of water-in-oil droplets have been utilized to construct artificial cells and simulate human body environment. However, the performance of subcellular structure involved metabolism in emulsion droplets has not been explored, and the underlying mechanism is still being elucidated. In this work, drug metabolism is presented on the basis of great amounts of microcompartments formed of picoliter-volume droplets with different radius (R), using a commercial four-way valve as a droplet generator. A model substrate, phenacetin, and its metabolite, paracetamol, are quantitatively analyzed by liquid-chromatography (LC) tandem mass spectrometry (MS/MS), and the reaction kinetics is characterized. In microdroplets of varying size (R = 18, 27, 42, and 51 μm, respectively), both conversion ratio and reaction rate constant of the metabolism are influenced in different degree. For instance, the substrate conversion ratio after 60 min of incubation in R = 27 μm droplets improves from 15% to 42%, and the reaction rate constant improves nearly five-fold, compared to that in bulk phase. The influence of microcompartment size on metabolism rate is further explored by simulation using a diffusion-reaction model. The droplet-based strategy is rapid, accurate and cost-efficient, fitting especially into biomimetic metabolism studies.
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47
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Ultrafast enzymatic digestion of proteins by microdroplet mass spectrometry. Nat Commun 2020; 11:1049. [PMID: 32103000 PMCID: PMC7044307 DOI: 10.1038/s41467-020-14877-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 01/21/2020] [Indexed: 11/15/2022] Open
Abstract
Enzymatic digestion for protein sequencing usually requires much time, and does not always result in high sequence coverage. Here we report the use of aqueous microdroplets to accelerate enzymatic reactions and, in particular, to improve protein sequencing. When a room temperature aqueous solution containing 10 µM myoglobin and 5 µg mL−1 trypsin is electrosonically sprayed (−3 kV) from a homemade setup to produce tiny (∼9 µm) microdroplets, we obtain 100% sequence coverage in less than 1 ms of digestion time, in sharp contrast to 60% coverage achieved by incubating the same solution at 37 °C for 14 h followed by analysis with a commercial electrospray ionization source that produces larger (∼60 µm) droplets. We also confirm the sequence of the therapeutic antibody trastuzumab (∼148 kDa), with a sequence coverage of 100% for light chains and 85% for heavy chains, demonstrating the practical utility of microdroplets in drug development. Mass spectrometry (MS)-based protein sequencing usually relies on in-solution proteolytic digestion, which is time-consuming and inefficient for certain proteins. Here, the authors achieve full protein sequence coverage in less than 1 ms by subjecting protein-protease mixtures to electrosonic spray ionization-MS.
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48
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Gnanamani E, Yan X, Zare RN. Chemoselective N‐Alkylation of Indoles in Aqueous Microdroplets. Angew Chem Int Ed Engl 2020; 59:3069-3072. [DOI: 10.1002/anie.201913069] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 12/12/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Elumalai Gnanamani
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305-5080 USA
- Department of ChemistryFudan University Shanghai 200438 China
| | - Xin Yan
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305-5080 USA
- Department of ChemistryTexas A&M University 580 Ross Street College Station TX 77843-3255 USA
| | - Richard N. Zare
- Department of ChemistryStanford University 333 Campus Drive Stanford CA 94305-5080 USA
- Department of ChemistryFudan University Shanghai 200438 China
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49
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Cavell AC, Krasecki VK, Li G, Sharma A, Sun H, Thompson MP, Forman CJ, Guo SY, Hickman RJ, Parrish KA, Aspuru-Guzik A, Cronin L, Gianneschi NC, Goldsmith RH. Optical monitoring of polymerizations in droplets with high temporal dynamic range. Chem Sci 2020; 11:2647-2656. [PMID: 34084323 PMCID: PMC8157680 DOI: 10.1039/c9sc05559b] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/02/2020] [Indexed: 12/23/2022] Open
Abstract
The ability to optically monitor a chemical reaction and generate an in situ readout is an important enabling technology, with applications ranging from the monitoring of reactions in flow, to the critical assessment step for combinatorial screening, to mechanistic studies on single reactant and catalyst molecules. Ideally, such a method would be applicable to many polymers and not require only a specific monomer for readout. It should also be applicable if the reactions are carried out in microdroplet chemical reactors, which offer a route to massive scalability in combinatorial searches. We describe a convenient optical method for monitoring polymerization reactions, fluorescence polarization anisotropy monitoring, and show that it can be applied in a robotically generated microdroplet. Further, we compare our method to an established optical reaction monitoring scheme, the use of Aggregation-Induced Emission (AIE) dyes, and find the two monitoring schemes offer sensitivity to different temporal regimes of the polymerization, meaning that the combination of the two provides an increased temporal dynamic range. Anisotropy is sensitive at early times, suggesting it will be useful for detecting new polymerization "hits" in searches for new reactivity, while the AIE dye responds at longer times, suggesting it will be useful for detecting reactions capable of reaching higher molecular weights.
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Affiliation(s)
- Andrew C Cavell
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
| | - Veronica K Krasecki
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
| | - Guoping Li
- Department of Chemistry, Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
| | - Abhishek Sharma
- School of Chemistry, University of Glasgow Joseph Black Building, University Avenue Glasgow Scotland G12 8QQ UK
| | - Hao Sun
- Department of Chemistry, Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
| | - Matthew P Thompson
- Department of Chemistry, Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
| | - Christopher J Forman
- Department of Chemistry, Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
| | - Si Yue Guo
- Department of Chemistry, University of Toronto 80 St. George Street Toronto Ontario M5S 3H6 Canada
- Department of Computer Science, University of Toronto 40 St. George Street Toronto Ontario M5S 2E4 Canada
| | - Riley J Hickman
- Department of Chemistry, University of Toronto 80 St. George Street Toronto Ontario M5S 3H6 Canada
- Department of Computer Science, University of Toronto 40 St. George Street Toronto Ontario M5S 2E4 Canada
| | - Katherine A Parrish
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
| | - Alán Aspuru-Guzik
- Department of Chemistry, University of Toronto 80 St. George Street Toronto Ontario M5S 3H6 Canada
- Department of Computer Science, University of Toronto 40 St. George Street Toronto Ontario M5S 2E4 Canada
- Canadian Institute for Advanced Research (CIFAR) Senior Fellow Toronto Ontario M5S 1M1 Canada
- CIFAR Artificial Intelligence Chair, Vector Institute Toronto Ontario M5S 1M1 Canada
| | - Leroy Cronin
- School of Chemistry, University of Glasgow Joseph Black Building, University Avenue Glasgow Scotland G12 8QQ UK
| | - Nathan C Gianneschi
- Department of Chemistry, Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
| | - Randall H Goldsmith
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
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50
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Luo K, Li J, Cao Y, Liu C, Ge J, Chen H, Zare RN. Reaction of chloroauric acid with histidine in microdroplets yields a catalytic Au-(His) 2 complex. Chem Sci 2020; 11:2558-2565. [PMID: 34084419 PMCID: PMC8157187 DOI: 10.1039/c9sc06221a] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 01/29/2020] [Indexed: 01/17/2023] Open
Abstract
An aqueous solution containing histidine (His, 100 μM) and chloroauric acid (HAuCl4, 10 μM) is electrosprayed (-4.5 kV) from a capillary (50 μm in diameter) with N2 nebulizing gas (120 psi). The resulting microdroplets entered a mass spectrometer with a 2 cm flight path. The mass spectrum recorded in negative ion mode showed several peaks including the Au5 nanocluster with the major one being [Au + 2His-2H]-, which is a catalytically active species. The reaction time was less 1 ms, and the yield of [Au + 2His-2H]- was 76%. In contrast, the bulk reaction for the same concentration run at room temperature for 2 h did not produce this species but instead formed Au10 nanocluster. When a solution of water and acetonitrile (1 : 1) containing indoline (100 mM) and the phenylacetylene (200 mM) as well as histidine and chloroauric acid at the same concentrations as above was electrosprayed, the mass spectrum showed the formation of the intermediate [Au + 2His + phenylacetylene + H]+. Upon collecting the microdroplets, the 4-methyl-4,6-diphenyl-1,2-dihydro-4H-pyrrolo[3,2,1-ij] quinolone product was observed by 1H nuclear magnetic resonance and liquid chromatography with a yield of 44%. The microdroplet synthesis using the Au-(His)2 complex as a catalyst was scaled up using room-temperature ultrasonic nebulization to produce the product at the rate of 35 mg min-1, which is semi-preparative and demonstrates the promise of using microdroplet reactions for chemical synthesis.
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Affiliation(s)
- Kai Luo
- Department of Chemistry, Fudan University Shanghai 200438 China
| | - Jia Li
- Department of Chemistry, Fudan University Shanghai 200438 China
| | - Yufei Cao
- Department of Chemical Engineering, Key Lab for Industrial Biocatalysis, Ministry of Education, Tsinghua University Beijing 100084 China
| | - Chengyuan Liu
- Department of Chemistry, Fudan University Shanghai 200438 China
| | - Jun Ge
- Department of Chemical Engineering, Key Lab for Industrial Biocatalysis, Ministry of Education, Tsinghua University Beijing 100084 China
| | - Hao Chen
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology Newark NJ 07102 USA
| | - Richard N Zare
- Department of Chemistry, Fudan University Shanghai 200438 China
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