1
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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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2
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Westhoff P, Weber APM. The role of metabolomics in informing strategies for improving photosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1696-1713. [PMID: 38158893 DOI: 10.1093/jxb/erad508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 12/29/2023] [Indexed: 01/03/2024]
Abstract
Photosynthesis plays a vital role in acclimating to and mitigating climate change, providing food and energy security for a population that is constantly growing, and achieving an economy with zero carbon emissions. A thorough comprehension of the dynamics of photosynthesis, including its molecular regulatory network and limitations, is essential for utilizing it as a tool to boost plant growth, enhance crop yields, and support the production of plant biomass for carbon storage. Photorespiration constrains photosynthetic efficiency and contributes significantly to carbon loss. Therefore, modulating or circumventing photorespiration presents opportunities to enhance photosynthetic efficiency. Over the past eight decades, substantial progress has been made in elucidating the molecular basis of photosynthesis, photorespiration, and the key regulatory mechanisms involved, beginning with the discovery of the canonical Calvin-Benson-Bassham cycle. Advanced chromatographic and mass spectrometric technologies have allowed a comprehensive analysis of the metabolite patterns associated with photosynthesis, contributing to a deeper understanding of its regulation. In this review, we summarize the results of metabolomics studies that shed light on the molecular intricacies of photosynthetic metabolism. We also discuss the methodological requirements essential for effective analysis of photosynthetic metabolism, highlighting the value of this technology in supporting strategies aimed at enhancing photosynthesis.
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Affiliation(s)
- Philipp Westhoff
- CEPLAS Plant Metabolomics and Metabolism Laboratory, Heinrich-Heine-University, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | - Andreas P M Weber
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Science (CEPLAS), Heinrich-Heine-University, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
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3
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Thøgersen J, Madzharova F, Weidner T, Jensen F. Aqueous pyruvate partly dissociates under deep ultraviolet irradiation but is resilient to near ultraviolet excitation. Nat Commun 2024; 15:1978. [PMID: 38438353 PMCID: PMC10912111 DOI: 10.1038/s41467-024-46309-5] [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: 11/08/2023] [Accepted: 02/14/2024] [Indexed: 03/06/2024] Open
Abstract
The deep ultraviolet photochemistry of aqueous pyruvate is believed to have been essential to the origin of life, and near ultraviolet excitation of pyruvate in aqueous aerosols is assumed to contribute significantly to the photochemistry of the Earth's atmosphere. However, the primary photochemistry of aqueous pyruvate is unknown. Here we study the susceptibility of aqueous pyruvate to photodissociation by deep ultraviolet and near ultraviolet irradiation with femtosecond spectroscopy supported by density functional theory calculations. The primary photo-dynamics of the aqueous pyruvate show that upon deep-UV excitation at 200 nm, about one in five excited pyruvate anions have dissociated by decarboxylation 100 ps after the excitation, while the rest of the pyruvate anions return to the ground state. Upon near-UV photoexcitation at a wavelength of 340 nm, the dissociation yield of aqueous pyruvate 200 ps after the excitation is insignificant and no products are observed. The experimental results are explained by our calculations, which show that aqueous pyruvate anions excited at 200 nm have sufficient excess energy for decarboxylation, whereas excitation at 340 nm provides the aqueous pyruvate anions with insufficient energy to overcome the decarboxylation barrier.
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Affiliation(s)
- Jan Thøgersen
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000, Aarhus C, Denmark
| | - Fani Madzharova
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000, Aarhus C, Denmark
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000, Aarhus C, Denmark
| | - Frank Jensen
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000, Aarhus C, Denmark.
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4
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Tian YM, Silva W, Gschwind RM, König B. Accelerated photochemical reactions at oil-water interface exploiting melting point depression. Science 2024; 383:750-756. [PMID: 38359135 DOI: 10.1126/science.adl3092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 01/11/2024] [Indexed: 02/17/2024]
Abstract
Water can accelerate a variety of organic reactions far beyond the rates observed in classical organic solvents. However, using pure water as a solvent introduces solubility constraints that have limited the applicability of efficient photochemistry in particular. We report here the formation of aggregates between pairs of arenes, heteroarenes, enamines, or esters with different electron affinities in an aqueous medium, leading to an oil-water phase boundary through substrate melting point depression. The active hydrogen atoms in the reactants engage in hydrogen bonds with water, thereby accelerating photochemical reactions. This methodology realizes appealingly simple conditions for aqueous coupling reactions of complex solid molecules, including complex drug molecules that are poorly soluble in water.
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Affiliation(s)
- Ya-Ming Tian
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, 93040 Regensburg, Germany
| | - Wagner Silva
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, 93040 Regensburg, Germany
| | - Ruth M Gschwind
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, 93040 Regensburg, Germany
| | - Burkhard König
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, 93040 Regensburg, Germany
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5
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Li M, Boothby C, Continetti RE, Grassian VH. Size-Dependent Sigmoidal Reaction Kinetics for Pyruvic Acid Condensation at the Air-Water Interface in Aqueous Microdroplets. J Am Chem Soc 2023; 145:22317-22321. [PMID: 37787586 PMCID: PMC10591466 DOI: 10.1021/jacs.3c08249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Indexed: 10/04/2023]
Abstract
The chemistry of pyruvic acid (PA) under thermal dark conditions is limited in bulk solutions, but in microdroplets it is shown to readily occur. Utilizing in situ micro-Raman spectroscopy as a probe, we investigated the chemistry of PA within aqueous microdroplets in a relative humidity- and temperature-controlled environmental cell. We found that PA undergoes a condensation reaction to yield mostly zymonic acid. Interestingly, the reaction follows a size-dependent sigmoidal kinetic profile, i.e., an induction period followed by reaction and then completion. The induction time is linearly proportional to the surface area (R2), and the maximum apparent reaction rate is proportional to the surface-to-volume ratio (1/R), showing that both the induction and reaction occur at the air-water interface. Furthermore, the droplet size is shown to be dynamic due to changes in droplet composition and re-equilibration with the relative humidity within the environmental cell as the reaction proceeds. Overall, the size-dependent sigmoidal kinetics, shown for the first time in microdroplets, demonstrates the complexity of the reaction mechanism and the importance of the air-water interface in the pyruvic acid condensation reaction.
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Affiliation(s)
- Meng Li
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
| | - Christian Boothby
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
| | - Robert E. Continetti
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
| | - Vicki H. Grassian
- Department of Chemistry and
Biochemistry, University of California San
Diego, La Jolla, California 92093, United States
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6
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Deal A, Smith AE, Oyala KM, Campolo GH, Rugeley BE, Mose TA, Talley DL, Cooley CB, Rapf RJ. Infrared Reflection-Absorption Spectroscopy of α-Keto Acids at the Air-Water Interface: Effects of Chain Length and Headgroup on Environmentally Relevant Surfactant Films. J Phys Chem A 2023; 127:4137-4151. [PMID: 37103984 PMCID: PMC10184673 DOI: 10.1021/acs.jpca.3c01266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/12/2023] [Indexed: 04/28/2023]
Abstract
A variety of organic surfactants are found at air-water interfaces in natural environments, including on the surfaces of aqueous aerosols. The structure and morphology of these organic films can have profound impacts on material transfer between the gas and condensed phases, the optical properties of atmospheric aerosol, and chemical processing at air-water interfaces. Combined, these effects can have significant impacts on climate via radiative forcing, but our understanding of organic films at air-water interfaces is incomplete. Here, we examine the impact of the polar headgroup and alkyl tail length on the structure and morphology of organic monolayers at the air-water interfaces. First, we focus on the substituted carboxylic acids, α-keto acids, using Langmuir isotherms and infrared reflection absorption spectroscopy (IR-RAS) to elucidate key structures and phase behaviors of α-keto acids with a range of surface activities. We show that the structure of α-keto acids, both soluble and insoluble, at water surfaces is a compromise between van der Waals interactions of the hydrocarbon tail and hydrogen bonding interactions involving the polar headgroup. Then, we use this new data set regarding α-keto acid films at water surfaces to examine the role of the polar headgroup on organic films using a similar substituted carboxylic acid (α-hydroxystearic acid), an unsubstituted carboxylic acid (stearic acid), and an alcohol (stearyl alcohol). We show that the polar headgroup and its hydrogen bonding interactions can significantly affect the orientation of amphiphiles at air-water interfaces. Here, we provide side-by-side comparisons of Langmuir isotherms and IR-RA spectra for a set of environmentally relevant organic amphiphiles with a range of alkyl tail lengths and polar headgroup structures.
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Affiliation(s)
- Alexandra
M. Deal
- Department
of Chemistry and Cooperative Institute for Research in Environmental
Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Abigail E. Smith
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Krista M. Oyala
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Giovanna H. Campolo
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Burgess E. Rugeley
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Tim A. Mose
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Denver L. Talley
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Christina B. Cooley
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Rebecca J. Rapf
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
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7
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Deal AM, Vaida V. Oxygen Effect on the Ultraviolet-C Photochemistry of Lactic Acid. J Phys Chem A 2023; 127:2936-2945. [PMID: 36962071 DOI: 10.1021/acs.jpca.3c00992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023]
Abstract
Lactic acid, a small α-hydroxyacid, is ubiquitous in both indoor and outdoor environments. Recently, the photochemistry of lactic acid has garnered interest among the abiotic organic chemistry community as it would have been present in abiotic settings and photoactive with the high-energy solar radiation that would have been available in the low oxygen early Earth environment. Additionally, we propose that the photochemistry of lactic acid is relevant to modern Earth during indoor ultraviolet-C (UVC) sterilization procedures as lactic acid is emitted by humans and is thus prevalent in indoor environments where UVC sterilization is increasingly being used. Here, we study the oxygen effect on the gas phase photolysis of lactic acid using Fourier-transform infrared (FTIR) spectroscopy and isotopically labeled oxygen (18O2). We find that the major products of gas phase lactic acid photolysis are CO2, CO, acetaldehyde, and acetic acid. Furthermore, these products are the same with or without added oxygen, but the partial pressures of produced CO2, CO, and acetaldehyde increase with the amount of added oxygen. Notably, the added oxygen is primarily incorporated into produced CO2 and CO, while little or none is incorporated into acetaldehyde. We combine the results presented here with those in the literature to propose a mechanism for the gas phase photolysis of lactic acid and the role of oxygen in this mechanism. Finally, we compare the output of a krypton-chloride excimer lamp (λ = 222 nm), one of the lamps proposed for UVC sterilization procedures, to the absorption of lactic acid. We show that lactic acid would be photoactive during UVC sterilization procedures, and we use the gas phase results presented here and aqueous lactic acid photolysis results previously published to assess potential byproducts from lactic acid reactions during UVC sterilization procedures.
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Affiliation(s)
- Alexandra M Deal
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Veronica Vaida
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
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8
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Guo Z, Kodikara D, Albi LS, Hatano Y, Chen G, Yoshimura C, Wang J. Photodegradation of organic micropollutants in aquatic environment: Importance, factors and processes. WATER RESEARCH 2023; 231:118236. [PMID: 36682233 DOI: 10.1016/j.watres.2022.118236] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 02/22/2022] [Accepted: 02/23/2022] [Indexed: 06/17/2023]
Abstract
Photochemical reactions widely occur in the aquatic environment and play fundamental roles in aquatic ecosystems. In particular, solar-induced photodegradation is efficient for many organic micropollutants (OMPs), especially those that cannot undergo hydrolysis or biodegradation, and thus can mitigate chemical pollution. Recent reports indicate that photodegradation may play a more important role than biodegradation in many OMP transformations in the aquatic environment. Photodegradation can be influenced by the water matrix such as pH, inorganic ions, and dissolved organic matter (DOM). The effect of the water matrix such as DOM on photodegradation is complex, and new insights concerning the disparate effects of DOM have recently been reported. In addition, the photodegradation process is also influenced by physical factors such as latitude, water depth, and temporal variations in sunlight as these factors determine the light conditions. However, it remains challenging to gain an overview of the importance of photodegradation in the aquatic environment because the reactions involved are diverse and complex. Therefore, this review provides a concise summary of the importance of photodegradation and the major processes related to the photodegradation of OMPs, with particular attention given to recent progress on the major reactions of DOM. In addition, major knowledge gaps in this field of environmental photochemistry are highlighted.
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Affiliation(s)
- Zhongyu Guo
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
| | - Dilini Kodikara
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
| | - Luthfia Shofi Albi
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
| | - Yuta Hatano
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
| | - Guo Chen
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
| | - Chihiro Yoshimura
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan.
| | - Jieqiong Wang
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
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9
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Bready CJ, Fowler VR, Juechter LA, Kurfman LA, Mazaleski GE, Shields GC. The driving effects of common atmospheric molecules for formation of prenucleation clusters: the case of sulfuric acid, formic acid, nitric acid, ammonia, and dimethyl amine. ENVIRONMENTAL SCIENCE: ATMOSPHERES 2022; 2:1469-1486. [PMID: 36561556 PMCID: PMC9648633 DOI: 10.1039/d2ea00087c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/30/2022] [Indexed: 11/12/2022]
Abstract
How secondary aerosols form is critical as aerosols' impact on Earth's climate is one of the main sources of uncertainty for understanding global warming. The beginning stages for formation of prenucleation complexes, that lead to larger aerosols, are difficult to decipher experimentally. We present a computational chemistry study of the interactions between three different acid molecules and two different bases. By combining a comprehensive search routine covering many thousands of configurations at the semiempirical level with high level quantum chemical calculations of approximately 1000 clusters for every possible combination of clusters containing a sulfuric acid molecule, a formic acid molecule, a nitric acid molecule, an ammonia molecule, a dimethylamine molecule, and 0-5 water molecules, we have completed an exhaustive search of the DLPNO-CCSD(T)/CBS//ωB97X-D/6-31++G** Gibbs free energy surface for this system. We find that the detailed geometries of each minimum free energy cluster are often more important than traditional acid or base strength. Addition of a water molecule to a dry cluster can enhance stabilization, and we find that the (SA)(NA)(A)(DMA)(W) cluster has special stability. Equilibrium calculations of SA, FA, NA, A, DMA, and water using our quantum chemical ΔG° values for cluster formation and realistic estimates of the concentrations of these monomers in the atmosphere reveals that nitric acid can drive early stages of particle formation just as efficiently as sulfuric acid. Our results lead us to believe that particle formation in the atmosphere results from the combination of many different molecules that are able to form highly stable complexes with acid molecules such as SA, NA, and FA.
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Affiliation(s)
- Conor J. Bready
- Department of Chemistry, Furman UniversityGreenvilleSouth Carolina 29613USA
| | - Vance R. Fowler
- Department of Chemistry, Furman UniversityGreenvilleSouth Carolina 29613USA
| | - Leah A. Juechter
- Department of Chemistry, Furman UniversityGreenvilleSouth Carolina 29613USA
| | - Luke A. Kurfman
- Department of Chemistry, Furman UniversityGreenvilleSouth Carolina 29613USA
| | - Grace E. Mazaleski
- Department of Chemistry, Furman UniversityGreenvilleSouth Carolina 29613USA
| | - George C. Shields
- Department of Chemistry, Furman UniversityGreenvilleSouth Carolina 29613USA
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10
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Deal AM, Vaida V. Infrared Reflection–Absorption Spectroscopy of α-Hydroxyacids at the Water–Air Interface. J Phys Chem A 2022; 126:8280-8294. [DOI: 10.1021/acs.jpca.2c04462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexandra M. Deal
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Veronica Vaida
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
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11
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Frandsen BN, Vaida V. Spectroscopy of Retinoic Acid at the Air-Water Interface. J Phys Chem A 2022; 126:6908-6919. [PMID: 36129815 DOI: 10.1021/acs.jpca.2c04873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The spectroscopy of all-trans-retinoic acid (ATRA), an important molecule of biological origin that can be found in nature, is investigated at the air-water interface using UV-Vis and IR reflection spectroscopy. We employ a UV-Vis reflection absorption spectroscopy (RAS) experiment along with infrared reflection absorption spectroscopy (IR-RAS) to probe ATRA at the air-water interface. We elucidate the factors influencing the spectroscopy of ATRA at the air-water interface and compare its spectra at the water surface with results of bulk samples obtained with conventional spectroscopic methods and computational chemistry. Monolayers of pure ATRA as well as mixed ATRA with stearic-d35 acid were prepared, and the spectroscopy reveals that ATRA forms J-aggregates with itself, causing a significant redshift of its S0 to S1 electronic transition. Pure ATRA monolayers are found to be unstable at the air-water interface and are lost from the surface over time due to the formation of aggregates. The mixture of ATRA and stearic-d35 acid has been shown to stabilize the monolayers and inhibit the loss of surface ATRA. On the basis of our observations, we propose that ATRA could be a significant photosensitizer in natural aqueous environments.
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Affiliation(s)
- Benjamin N Frandsen
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States.,Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, UCB 216, Boulder, Colorado 80309, United States
| | - Veronica Vaida
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States.,Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, UCB 216, Boulder, Colorado 80309, United States
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12
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Miller TM, Wiens JP, Viggiano AA, Ard SG, Shuman NS. Thermal Electron Attachment to Pyruvic Acid, Thermal Detachment from the Parent Anion, and the Electron Affinity of Pyruvic Acid. J Phys Chem A 2022; 126:5545-5551. [PMID: 35951543 DOI: 10.1021/acs.jpca.2c04036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The kinetics of electron attachment to pyruvic acid (CH3COCOOH) and thermal detachment from the resulting parent anion were measured from 300-515 K using a flowing afterglow─Langmuir probe apparatus. An adiabatic electron affinity (EA) for pyruvic acid was derived, 0.84 ± 0.02 eV. Electron attachment rate constants to pyruvic acid of 2.1 × 10-8 and 1.2 × 10-8 were measured at 300 and 400 K, respectively. Rate constants at higher temperatures are less well-defined due to possible contributions from attachment to zymonic open ketone, an endemic impurity in pyruvic acid. Similarly, unimolecular detachment rates are complicated by secondary proton transfer reaction of the pyruvic acid anion with pyruvic acid to yield an 87 Da anion. The possible contributions from these chemistries are considered, and in all cases the equilibrium constant between attachment and detachment remains well-defined, allowing for determination of the EA.
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Affiliation(s)
- Thomas M Miller
- Boston College Institute for Scientific Research, Boston, Massachusetts 02549, United States
| | - Justin P Wiens
- Boston College Institute for Scientific Research, Boston, Massachusetts 02549, United States
| | - Albert A Viggiano
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, Albuquerque, New Mexico 87117, United States
| | - Shaun G Ard
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, Albuquerque, New Mexico 87117, United States
| | - Nicholas S Shuman
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, Albuquerque, New Mexico 87117, United States
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13
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Lesnicki D, Wank V, Cyran JD, Backus EHG, Sulpizi M. Lower degree of dissociation of pyruvic acid at water surfaces than in bulk. Phys Chem Chem Phys 2022; 24:13510-13513. [PMID: 35640627 DOI: 10.1039/d2cp01293f] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Understanding the acid/base behavior of environmentally relevant organic acids is of key relevance for accurate climate modelling. Here we investigate the effect of pH on the (de)protonation state of pyruvic acid at the air-water interface and in bulk by using the analytical techniques surface-specific vibrational sum frequency generation and attenuated total reflection spectroscopy. To provide a molecular interpretation of the observed behavior, simulations are carried out using a free energy perturbation approach in combination with electronic structure-based molecular dynamics. In both the experimental and theoretical results we observe that the protonated form of pyruvic acid is preferred at the air-water interface. The increased proton affinity is the result of the specific microsolvation at the interface.
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Affiliation(s)
- Dominika Lesnicki
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55099 Mainz, Germany.
| | - Veronika Wank
- University of Vienna, Faculty of Chemistry, Institute of Physical Chemistry, Währinger Straße 42, 1090 Vienna, Austria. .,University of Vienna, Vienna Doctoral School in Chemistry (DoSChem), Währinger Straße 42, 1090 Vienna, Austria
| | - Jenée D Cyran
- Department of Chemistry and Biochemistry, Baylor University, 76706 Waco, Texas, USA
| | - Ellen H G Backus
- University of Vienna, Faculty of Chemistry, Institute of Physical Chemistry, Währinger Straße 42, 1090 Vienna, Austria. .,University of Vienna, Vienna Doctoral School in Chemistry (DoSChem), Währinger Straße 42, 1090 Vienna, Austria
| | - Marialore Sulpizi
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55099 Mainz, Germany. .,Department of Physics, Ruhr Universität Bochum, 44780 Bochum, Germany
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14
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Lee C, Pohl MN, Ramphal IA, Yang W, Winter B, Abel B, Neumark DM. Evaporation and Molecular Beam Scattering from a Flat Liquid Jet. J Phys Chem A 2022; 126:3373-3383. [PMID: 35579333 DOI: 10.1021/acs.jpca.2c01174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An experimental setup for molecular beam scattering from flat liquid sheets has been developed, with the goal of studying reactions at gas-liquid interfaces for volatile liquids. Specifically, a crossed molecular beam instrument that can measure angular and translational energy distributions of scattered products has been adapted for liquid jet scattering. A microfluidic chip is used to create a stable flat liquid sheet inside vacuum from which scattering occurs, and both evaporation and scattering from this sheet are characterized using a rotatable mass spectrometer that can measure product time-of-flight distributions. This article describes the instrument and reports on the first measurements of evaporation of dodecane and Ne from a Ne-doped dodecane flat jet, as well as scattering of Ne from a flat jet of pure dodecane.
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Affiliation(s)
- Chin Lee
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Marvin N Pohl
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Isaac A Ramphal
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Walt Yang
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Bernd Winter
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Bernd Abel
- Department of Functional Surfaces, Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318 Leipzig, Germany.,Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University of Leipzig, Linnéstrasse 3, 04318 Leipzig, Germany
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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15
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Hammami F, Issaoui N. A DFT Study of the Hydrogen Bonded Structures of Pyruvic Acid–Water Complexes. FRONTIERS IN PHYSICS 2022. [DOI: 10.3389/fphy.2022.901736] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The molecular geometries of the possible conformations of pyruvic acid–water complexes (PA-(H2O)n = 1–4) have been fully optimized at DFT/B3LYP/6-311G++ (d, p) levels of calculation. Among several optimized molecular clusters, we present here the most stable molecular arrangements obtained when one, two, three, and four water molecules are hydrogen-bonded to a central pyruvic acid molecule. Appropriate topological and geometrical parameters are considered primary indicators of H-bond strength. Atoms in molecules analysis shows that pyruvic acid can form a ring structure with water, and the molecular structures are stabilized by both strong O–H⋅⋅⋅O and C–H⋅⋅⋅O hydrogen bonds. In large clusters, classical O–H⋅⋅⋅O hydrogen bonds still exist between water molecules, and a cage-like structure is built around some parts of the central molecule of pyruvic acid.
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16
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Corral Arroyo P, David G, Alpert PA, Parmentier EA, Ammann M, Signorell R. Amplification of light within aerosol particles accelerates in-particle photochemistry. Science 2022; 376:293-296. [PMID: 35420964 DOI: 10.1126/science.abm7915] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Optical confinement (OC) structures the optical field and amplifies light intensity inside atmospheric aerosol particles, with major consequences for sunlight-driven aerosol chemistry. Although theorized, the OC-induced spatial structuring has so far defied experimental observation. Here, x-ray spectromicroscopic imaging complemented by modeling provides direct evidence for OC-induced patterning inside photoactive particles. Single iron(III)-citrate particles were probed using the iron oxidation state as a photochemical marker. Based on these results, we predict an overall acceleration of photochemical reactions by a factor of two to three for most classes of atmospheric aerosol particles. Rotation of free aerosol particles and intraparticle molecular transport generally accelerate the photochemistry. Given the prevalence of OC effects, their influence on aerosol particle photochemistry should be considered by atmospheric models.
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Affiliation(s)
- Pablo Corral Arroyo
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Grégory David
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Peter A Alpert
- Laboratory of Environmental Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Evelyne A Parmentier
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Markus Ammann
- Laboratory of Environmental Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Ruth Signorell
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
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17
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Harold SE, Bready CJ, Juechter LA, Kurfman LA, Vanovac S, Fowler VR, Mazaleski GE, Odbadrakh TT, Shields GC. Hydrogen-Bond Topology Is More Important Than Acid/Base Strength in Atmospheric Prenucleation Clusters. J Phys Chem A 2022; 126:1718-1728. [PMID: 35235333 DOI: 10.1021/acs.jpca.1c10754] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We explored the hypothesis that on the nanoscale level, acids and bases might exhibit different behavior than in bulk solution. Our study system consisted of sulfuric acid, formic acid, ammonia, and water. We calculated highly accurate Domain-based Local pair-Natural Orbital- Coupled-Cluster/Complete Basis Set (DLPNO-CCSD(T)/CBS) energies on DFT geometries and used the resulting Gibbs free energies for cluster formation to compute the overall equilibrium constants for every possible cluster. The equilibrium constants combined with the initial monomer concentrations were used to predict the formation of clusters at the top and the bottom of the troposphere. Our results show that formic acid is as effective as ammonia at forming clusters with sulfuric acid and water. The structure of formic acid is uniquely suited to form hydrogen bonds with sulfuric acid. Additionally, it can partner with water to form bridges from one side of sulfuric acid to the other, hence demonstrating that hydrogen bonding topology is more important than acid/base strength in these atmospheric prenucleation clusters.
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Affiliation(s)
- Shannon E Harold
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Conor J Bready
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Leah A Juechter
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Luke A Kurfman
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Sara Vanovac
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Vance R Fowler
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Grace E Mazaleski
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - Tuguldur T Odbadrakh
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
| | - George C Shields
- Department of Chemistry, Furman University, Greenville, South Carolina 29613, United States
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18
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Kappes K, Frandsen BN, Vaida V. Infrared spectroscopy of 2-oxo-octanoic acid in multiple phases. Phys Chem Chem Phys 2022; 24:6757-6768. [PMID: 35237773 DOI: 10.1039/d1cp05345k] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Alpha-keto acids are environmentally and biologically relevant species whose chemistry has been shown to be influenced by their local environment. Vibrational spectroscopy provides useful ways to probe the potential inter- and intramolecular interactions available to them in several phases. We measure and compare the IR spectra of 2-oxo-octanoic acid (2OOA) in the gas phase, solid phase, and at the air-water interface. With theoretical support, we assign many of the vibrational modes in each of the spectra. In the gas phase, two types of conformers are identified and distinguished, with the intramolecularly H-bonded form being the dominant type, while the second conformer type identified does not have an intramolecular hydrogen bond. The van der Waals interactions between molecules in solid 2OOA manifest C-H and CO vibrations lower in energy than in the gas phase and we propose an intermolecular hydrogen bonding scheme for the solid phase. At the air-water interface the hydrocarbon tails of 2OOA do interact with each other while the carbonyls appear to interact with water in the subphase, but not with neighboring 2OOA as might be expected of a closely packed surfactant film.
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Affiliation(s)
- Keaten Kappes
- Department of Chemistry, University of Colorado-Boulder, UCB 215, Boulder, CO 80309, USA. .,Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder, UCB 216, Boulder, CO 80309, USA
| | - Benjamin N Frandsen
- Department of Chemistry, University of Colorado-Boulder, UCB 215, Boulder, CO 80309, USA. .,Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder, UCB 216, Boulder, CO 80309, USA
| | - Veronica Vaida
- Department of Chemistry, University of Colorado-Boulder, UCB 215, Boulder, CO 80309, USA. .,Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder, UCB 216, Boulder, CO 80309, USA
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19
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Photochemistry of the pyruvate anion produces CO 2, CO, CH 3-, CH 3, and a low energy electron. Nat Commun 2022; 13:937. [PMID: 35177613 PMCID: PMC8854594 DOI: 10.1038/s41467-022-28582-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 02/01/2022] [Indexed: 11/09/2022] Open
Abstract
The photochemistry of pyruvic acid has attracted much scientific interest because it is believed to play critical roles in atmospheric chemistry. However, under most atmospherically relevant conditions, pyruvic acid deprotonates to form its conjugate base, the photochemistry of which is essentially unknown. Here, we present a detailed study of the photochemistry of the isolated pyruvate anion and uncover that it is extremely rich. Using photoelectron imaging and computational chemistry, we show that photoexcitation by UVA light leads to the formation of CO2, CO, and CH3−. The observation of the unusual methide anion formation and its subsequent decomposition into methyl radical and a free electron may hold important consequences for atmospheric chemistry. From a mechanistic perspective, the initial decarboxylation of pyruvate necessarily differs from that in pyruvic acid, due to the missing proton in the anion. Pyruvic acid and its conjugate base, the pyruvate anion, are largely present in the atmosphere. Here the authors, using photoelectron imaging and quantum chemistry calculations, investigate the photochemistry of isolated pyruvate anions initiated by UVA radiation and report the formation of CO2, CO, and CH3− further decomposing into CH3 and a free electron.
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20
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Deal AM, Frandsen BN, Vaida V. Lactic acid photochemistry following excitation of S
0
to S
1
at 220 to 250 nm. J PHYS ORG CHEM 2022. [DOI: 10.1002/poc.4316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Alexandra M. Deal
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder Boulder CO USA
| | - Benjamin N. Frandsen
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder Boulder CO USA
| | - Veronica Vaida
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder Boulder CO USA
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21
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Barquilla MDP, Mayes ML. Role of hydrogen bonding in bulk aqueous phase decomposition, complexation, and covalent hydration of pyruvic acid. Phys Chem Chem Phys 2022; 24:25151-25170. [DOI: 10.1039/d2cp03579k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The behavior of hydrogen bonding changes between the gas and aqueous phase, altering the mechanisms of various pyruvic acid processes and consequently affecting the aerosol formation in different environments.
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Affiliation(s)
- Michael Dave P. Barquilla
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, North Dartmouth, MA 02747, USA
| | - Maricris L. Mayes
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, North Dartmouth, MA 02747, USA
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22
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Jarraya M, Bellili A, Barreau L, Cubaynes D, Garcia GA, Poisson L, Hochlaf M. Probing the dynamics of the photo-induced decarboxylation of neutral and ionic pyruvic acid. Faraday Discuss 2022; 238:266-294. [DOI: 10.1039/d2fd00023g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of the electronically excited pyruvic acid (PA) and of its unimolecular decomposition upon single photon ionization are investigated by means of a table top fs laser and VUV...
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23
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Aqueous Photochemistry of 2-Oxocarboxylic Acids: Evidence, Mechanisms, and Atmospheric Impact. Molecules 2021; 26:molecules26175278. [PMID: 34500711 PMCID: PMC8433822 DOI: 10.3390/molecules26175278] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 08/27/2021] [Accepted: 08/29/2021] [Indexed: 11/17/2022] Open
Abstract
Atmospheric organic aerosols play a major role in climate, demanding a better understanding of their formation mechanisms by contributing multiphase chemical reactions with the participation of water. The sunlight driven aqueous photochemistry of small 2-oxocarboxylic acids is a potential major source of organic aerosol, which prompted the investigations into the mechanisms of glyoxylic acid and pyruvic acid photochemistry reviewed here. While 2-oxocarboxylic acids can be contained or directly created in the particles, the majorities of these abundant and available molecules are in the gas phase and must first undergo the surface uptake process to react in, and on the surface, of aqueous particles. Thus, the work also reviews the acid-base reaction that occurs when gaseous pyruvic acid meets the interface of aqueous microdroplets, which is contrasted with the same process for acetic acid. This work classifies relevant information needed to understand the photochemistry of aqueous pyruvic acid and glyoxylic acid and motivates future studies based on reports that use novel strategies and methodologies to advance this field.
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24
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Abstract
Theoretical chemists have been actively engaged for some time in processes such as ozone photodissociation, overtone photodissociation in nitric acid, pernitric acid, sulphuric acid, clusters and in small organic acids. The last of these have shown very different behaviours in the gas phase, liquid phase and importantly at the air–water interface in aqueous aerosols. The founder of molecular dynamics, B J Alder, pointed out long ago that hydrodynamic behaviour emerged when the symmetry of a random, thermalised population of hard spheres—billiard balls—was broken by a flux of energetic molecules. Despite this, efforts over two centuries to solve turbulence by finding top-down solutions to the Navier–Stokes equation have failed. It is time for theoretical chemistry to try a bottom-up solution. Gibbs free energy that drives the circulation arises from the entropy difference between the incoming low-entropy beam of visible and ultraviolet photons and the outgoing higher-entropy flux of infrared photons over the whole 4π solid angle. The role of the most energetic molecules with the highest velocities will affect the rovibrational line shapes of water, carbon dioxide and ozone in the far wings, where there is the largest effect on radiative transfer and hence on calculations of atmospheric temperature. The atmospheric state is determined by the interaction of radiation, chemistry and fluid dynamics on the microscopic scale, with propagation through the mesoscale to the macroscale. It will take theoretical chemistry to simulate that accurately. A challenging programme of research for theoretical chemistry is proposed, involving ab initio simulation by molecular dynamics of an air volume, starting in the upper stratosphere. The aim is to obtain scaling exponents for turbulence, providing a physical method for upscaling in numerical models. Turbulence affects chemistry, radiation and fluid dynamics at a fundamental, molecular level and is thus of basic concern to theoretical chemistry as it applies to the atmosphere, which consists of molecules in motion.
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25
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Deal AM, Rapf RJ, Vaida V. Water-Air Interfaces as Environments to Address the Water Paradox in Prebiotic Chemistry: A Physical Chemistry Perspective. J Phys Chem A 2021; 125:4929-4942. [PMID: 33979519 DOI: 10.1021/acs.jpca.1c02864] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The asymmetric water-air interface provides a dynamic aqueous environment with properties that are often very different than bulk aqueous or gaseous phases and promotes reactions that are thermodynamically, kinetically, or otherwise unfavorable in bulk water. Prebiotic chemistry faces a key challenge: water is necessary for life yet reduces the efficiency of many biomolecular synthesis reactions. This perspective considers water-air interfaces as auspicious reaction environments for abiotic synthesis. We discuss recent evidence that (1) water-air interfaces promote condensation reactions including peptide synthesis, phosphorylation, and oligomerization; (2) photochemistry at water-air interfaces may have been a significant source of prebiotic molecular complexity, given the lack of oxygen and increased availability of near-ultraviolet radiation on early Earth; and (3) water-air interfaces can promote spontaneous reduction and oxidation reactions, potentially providing protometabolic pathways. Life likely began within a relatively short time frame, and water-air interfaces offer promising environments for simultaneous and efficient biomolecule production.
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Affiliation(s)
- Alexandra M Deal
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Rebecca J Rapf
- Department of Chemistry, Trinity University, 1 Trinity Place, San Antonio, Texas 78212, United States
| | - Veronica Vaida
- Department of Chemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
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