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Dutta J, Tiwari S. Aromatic nucleophilic substitution (s
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ar) reactions of halo‐substituted dinitrobenzene in liposome reaction media: Effect of reaction medium and role of halogen leaving group. J PHYS ORG CHEM 2021. [DOI: 10.1002/poc.4182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jyoti Dutta
- Department of Chemistry Institute of Chemical Technology Mumbai Maharashtra India
| | - Shraeddha Tiwari
- Department of Chemistry Institute of Chemical Technology Mumbai Maharashtra India
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2
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Chern MS, Okamoto Y, Suga K, Watanabe N, Umakoshi H. Changes Caused by Liposomes to the Belousov-Zhabotinsky Reaction. J Phys Chem B 2020; 124:9862-9869. [PMID: 33086793 DOI: 10.1021/acs.jpcb.0c06413] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Belousov-Zhabotinsky (BZ) reaction has been applied to give autonomous dynamic behaviors to artificial systems. This reaction is conducted in an aqueous system, but it produces some hydrophobic intermediates, such as bromine. On the basis of previous works about reactions in the lipid bilayer, we investigated how liposome membranes (water-oil interface) affect the BZ reaction. Herein diacylglycerophosphocholine (PC) molecules with a variety of hydrocarbon tails were selected as components of liposomes, and the BZ reaction in the presence of the liposomes was characterized. As a result, membrane fluidity was the main characteristic leading to changes in the reaction behavior. The decrease of the frequency of oscillations was relevant to membrane fluidity, suggesting the interaction of bromine species in the hydrophobic site of the liposomes. In addition, the heterogeneous membrane (so+ld) of DMPC showed a fast decrease in the amplitude of oscillations. Conclusively, characteristics of the hydrophobic environment play a role in the reaction.
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Affiliation(s)
- Michael S Chern
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 5608531, Japan
| | - Yukihiro Okamoto
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 5608531, Japan
| | - Keishi Suga
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 5608531, Japan
| | - Nozomi Watanabe
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 5608531, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 5608531, Japan
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3
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Abstract
A method to detect the L-proline- (L-Pro-) catalyzed Michael addition reaction in model biomembranes has been established, using N-[p(2-benzimidazolyl)phenyl]maleimide and acetone as reactants. The effect of liposome membranes on this reaction was kinetically analyzed using fluorescence spectroscopy. The kinetics of the reaction were different from those of the constituent lipids of the liposomes. Zwitterionic 1,2-dipalmitoyl-sn-glycero-3-phosphocholine liposome, which is in the solid-ordered phase, had a better value of reaction rate, suggesting that the reaction rate constants of this reaction in liposome membrane systems could be regulated by the characteristics of the liposome membrane (i.e., the phase state and surface charge). Based on the results obtained, a plausible model of the L-Pro-catalyzed Michael addition reaction was discussed. The obtained results provide us with an easily detectable method to assess the reactivity of L-Pro in biological systems.
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Serrano-Luginbühl S, Ruiz-Mirazo K, Ostaszewski R, Gallou F, Walde P. Soft and dispersed interface-rich aqueous systems that promote and guide chemical reactions. Nat Rev Chem 2018. [DOI: 10.1038/s41570-018-0042-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Hirose M, Fujiwara S, Ishigami T, Suga K, Okamoto Y, Umakoshi H. Liposome Membranes Assist the l-Proline-catalyzed Aldol Reaction of Acetone and p-Nitrobenzaldehyde in Water. CHEM LETT 2018. [DOI: 10.1246/cl.180180] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Masanori Hirose
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Shimpei Fujiwara
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Takaaki Ishigami
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Keishi Suga
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Yukihiro Okamoto
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
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Luginbühl S, Iwasaki F, Chirackal Varkey E, Umakoshi H, Walde P. A Novel Role of Vesicles as Templates for the Oxidation and Oligomerization of p-Aminodiphenylamine by Cytochrome c. Helv Chim Acta 2017. [DOI: 10.1002/hlca.201700027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sandra Luginbühl
- Polymer Chemistry Group; Department of Materials (D-MATL); ETH Zürich; Vladimir Prelog-Weg 5 CH-8093 Zürich
| | - Fumihiko Iwasaki
- Polymer Chemistry Group; Department of Materials (D-MATL); ETH Zürich; Vladimir Prelog-Weg 5 CH-8093 Zürich
- Bio-Inspired Chemical Engineering Lab; Division of Chemical Engineering; Graduate School of Engineering Science; Osaka University; 1-3 Machikaneyamacho Toyonaka Osaka 560-8531 Japan
| | - Elizabeth Chirackal Varkey
- Polymer Chemistry Group; Department of Materials (D-MATL); ETH Zürich; Vladimir Prelog-Weg 5 CH-8093 Zürich
| | - Hiroshi Umakoshi
- Bio-Inspired Chemical Engineering Lab; Division of Chemical Engineering; Graduate School of Engineering Science; Osaka University; 1-3 Machikaneyamacho Toyonaka Osaka 560-8531 Japan
| | - Peter Walde
- Polymer Chemistry Group; Department of Materials (D-MATL); ETH Zürich; Vladimir Prelog-Weg 5 CH-8093 Zürich
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Iwasaki F, Suga K, Okamoto Y, Umakoshi H. Enantioselective C-C Bond Formation Enhanced by Self-Assembly of Achiral Surfactants. ACS OMEGA 2017; 2:1447-1453. [PMID: 31457516 PMCID: PMC6641137 DOI: 10.1021/acsomega.7b00034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 03/30/2017] [Indexed: 05/12/2023]
Abstract
The use of achiral surfactant assemblies as a reaction platform for an alkylation reaction resulted in a high enantiomeric excess. Dilauryldimethylammonium bromide (DDAB) vesicles were modified with cholesterol to promote alkylation of N-(diphenylmethylene)glycine tert-butyl ester (DMGBE) with benzyl bromide, resulting in high conversion (∼90%) and high enantioselectivity (up to 80%). The R-enantiomer was formed on using the DDAB vesicles, whereas the use of phospholipid liposomes prepared from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) produced an excess of the S-enantiomer. Considering the chemical structures of the reaction substrates and amphiphiles as well as the membrane structures and properties of DDAB vesicles and DOPC liposomes, it is suggested that the enantiomeric excesses result from the location of the quaternary amine of the amphiphiles and the DMGBE at the outer surface of the membrane. We show that the enantioselective reaction at the surface of the self-assembly could be regulated by adjusting the chemical structures and resulting membrane properties of the self-assembly.
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Iwasaki F, Luginbühl S, Suga K, Walde P, Umakoshi H. Fluorescent Probe Study of AOT Vesicle Membranes and Their Alteration upon Addition of Aniline or the Aniline Dimer p-Aminodiphenylamine (PADPA). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:1984-1994. [PMID: 28161960 DOI: 10.1021/acs.langmuir.6b04480] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Artificial vesicles formed from sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in aqueous solution are used successfully as additives for enzymatic oligomerizations or polymerizations of aniline or the aniline dimer p-aminodiphenylamine (PADPA) under slightly acidic conditions (e.g., pH 4.3 with horseradish peroxidase and hydrogen peroxide as oxidants). In these systems, the reactions occur membrane surface-confined. Therefore, (i) the physicochemical properties of the vesicle membrane and (ii) the interaction of aniline or PADPA with the AOT membrane play crucial roles in the progress and final outcome of the reactions. For this reason, the properties of AOT vesicles with and without added aniline or PADPA were investigated by using two fluorescent membrane probes: 1,6-diphenyl-1,3,5-hexatriene (DPH) and 6-lauroyl-2-dimethylaminonaphthalene (Laurdan). DPH and Laurdan were used as "sensors" of the membrane fluidity, surface polarity, and membrane phase state. Moreover, the effect of hexanol, alone or in combination with aniline or PADPA, as a possible modifier of the AOT membrane, was also studied with the aim of evaluating whether the membrane fluidity and surface polarity is altered significantly by hexanol, which, in turn, may have an influence on the mentioned types of reactions. The data obtained indicate that the AOT vesicle membrane at room temperature and pH 4.3 (0.1 M NaH2PO4) is more fluid and has a more polar surface than in the case of fluid phospholipid vesicle membranes formed from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). Furthermore, the fluorescence measurements indicate that mixed AOT-hexanol membranes are less fluid than pure AOT membranes and that they have a lower surface polarity than pure AOT membranes. PADPA strongly binds to AOT and to mixed AOT/hexanol membranes and leads to drastic changes in the membrane properties (decrease in fluidity and surface polarity), resulting in Laurdan fluorescence spectra, which are characteristic for intramembrane phase separations (coexistence of ordered and disordered domains). This means that highly fluid AOT membranes transform upon the addition of PADPA into membranes that have ordered domains. Although the relevance of this finding for the enzymatic oligomerization of PADPA is not yet clear, it is also of interest if one likes to use heterogeneous vesicle membranes as additives for carrying out membrane surface-confined reactions that do not necessarily involve PADPA as a reactant.
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Affiliation(s)
- Fumihiko Iwasaki
- Bio-Inspired Chemical Engineering Lab, Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Sandra Luginbühl
- Laboratory of Polymer Chemistry, Department of Materials, ETH Zürich , Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Keishi Suga
- Bio-Inspired Chemical Engineering Lab, Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Peter Walde
- Laboratory of Polymer Chemistry, Department of Materials, ETH Zürich , Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Hiroshi Umakoshi
- Bio-Inspired Chemical Engineering Lab, Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
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Iwasaki F, Suga K, Okamoto Y, Umakoshi H. Liposomes Can Achieve Enantioselective C-C Bond Formation of an α-Amino Acid Derivative in Aqueous Media. ACS OMEGA 2017; 2:91-97. [PMID: 31457212 PMCID: PMC6640982 DOI: 10.1021/acsomega.6b00479] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 12/29/2016] [Indexed: 05/09/2023]
Abstract
We first report that a highly enantioselective C-C bond formation reaction was achieved with liposomes in aqueous media. Alkylation of N-(diphenylmethylene)glycine tert-butyl ester (DMGBE) with benzyl bromide was conducted in the presence of cetyltrimethylammonium bromide micelles, resulting in a high conversion of DMGBE but little enantiomeric excess (e.e.) of the product. The same reaction was then carried out in 1,2-dioleoyl-sn-glycero-3-phosphocholine liposome suspensions, where the e.e. values were high (at least 90 % (S)), indicating that the liposome membranes can behave as the promoter of the enantioselective reaction. Changing the type of lipid to 1,2-dipalmitoyl-sn-glycero-3-phosphocholine to form a more ordered bilayer membrane lowered the reaction conversion but still maintained high e.e.% , that is, >90 (S), regardless of lipid chirality. It is indicated that multiple interactions between the DMGBE intermediate and lipid molecules promoted the migration of the intermediate into the interior of the membrane, whose bottom side (Si face) could be free for alkylation. These results suggest that liposomes can promote and regulate the alkylation of amino acid derivatives.
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Luginbühl S, Bertschi L, Willeke M, Schuler LD, Walde P. How Anionic Vesicles Steer the Oligomerization of Enzymatically Oxidized p-Aminodiphenylamine (PADPA) toward a Polyaniline Emeraldine Salt (PANI-ES)-Type Product. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:9765-9779. [PMID: 27570882 DOI: 10.1021/acs.langmuir.6b02146] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The oxidation of the aniline dimer, p-aminodiphenylamine (PADPA), with Trametes versicolor laccase and O2 in an aqueous solution of pH 3.5 is controlled by negatively charged AOT (sodium bis(2-ethylhexyl) sulfosuccinate) vesicles. With vesicles, a product resembling polyaniline in its emeraldine salt form (PANI-ES) is obtained, in contrast to the reaction without vesicles where no such product is formed. To understand this observation, the product distribution and structures from the reaction with and without vesicles were determined by using partially selectively deuterated PADPA as a starting material and analyzing the products with HPLC-MS. We found that in the presence of vesicles the main product is obtained in about 50% yield, which is the N-C-para-coupled PADPA dimer that has spectroscopic properties of PANI-ES, as determined by time-dependent density functional theory (TD-DFT) calculations. A secondary reaction route leads to longer PADPA oligomers that must contain a phenazine core. Without vesicles, PADPA and its products undergo partial hydrolysis, but in the presence of vesicles, hydrolysis does not occur. Because molecular dynamics (MD) simulations show that the main intermediate oxidation product is embedded within the vesicle membrane, where the water content is very low, we propose that the microenvironment of the vesicle membrane protects the oxidation products from unwanted hydrolysis.
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Affiliation(s)
- Sandra Luginbühl
- Laboratory of Polymer Chemistry, Department of Materials, ETH Zürich , Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Louis Bertschi
- Laboratory of Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich , Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Martin Willeke
- Materials Science Education, Department of Materials, ETH Zürich , Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland
| | | | - Peter Walde
- Laboratory of Polymer Chemistry, Department of Materials, ETH Zürich , Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
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Suga K, Kondo D, Otsuka Y, Okamoto Y, Umakoshi H. Characterization of Aqueous Oleic Acid/Oleate Dispersions by Fluorescent Probes and Raman Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:7606-7612. [PMID: 27404017 DOI: 10.1021/acs.langmuir.6b02257] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Oleic acid (OA) and oleates form self-assembled structures dispersible in aqueous media. Herein, the physicochemical properties of OA/oleate assemblies were characterized using fluorescent probes and Raman spectroscopy, under relatively high dilution (<100 mM of total amphiphile) at 25 °C. Anisotropy analysis using 1,6-diphenyl-1,3,5-hexatriene showed that the microviscosity of the OA/oleate assembly was highest at pH 7.5 (the pH range of 6.9-10.6 was investigated). The fluorescence spectra of 6-lauroyl-2-dimethylaminonaphthalene revealed the dehydrated environments on membrane surfaces at pH < 7.7. The pH-dependent Raman peak intensity ratios, chain torsion (S = I1124/I1096) and chain packing (R = I2850/I2930), showed local maxima, indicating the occurrence of metastable phases, such as dispersed cubic phase (pH = 7.5), vesicle (pH = 8.5), and dispersed cylindrical micelle (pH = 9.7). These results suggest that large-scale OA/oleate assemblies could possess particular membrane properties in a narrow pH region, e.g., at pH 7.5, and 9.7.
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Affiliation(s)
- Keishi Suga
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Dai Kondo
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Yoko Otsuka
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Yukihiro Okamoto
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
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Ishigami T, Tauchi A, Suga K, Umakoshi H. Effect of Boundary Edge in DOPC/DPPC/Cholesterol Liposomes on Acceleration of l-Histidine Preferential Adsorption. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:6011-6019. [PMID: 27232976 DOI: 10.1021/acs.langmuir.5b04626] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In order to investigate the interaction of hydrophilic molecules with liposomal membranes, we employed 1-(4-(trimethylamino)phenyl)-6-phenyl-1,3,5-hexatriene and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(5-dimethylamino-1-naphthalenesulfonyl) as fluorescent probes to monitor the surface regions of the membrane, and the results for various liposomes were plotted in correlation diagrams. According to the formation of a variety of phase states, different tendencies of decreasing surface hydrophobicity were observed in the liposomes that were modified with high concentrations of cholesterol or in the liposomes that were composed of ternary components. These liposomes, with hydrophobic surfaces, also showed preferential adsorption of l-histidine (l-His), and the hydrophobicity of the liposomal membrane at the surface changed during l-His adsorption regardless of the initial liposomal properties. Furthermore, we revealed that accelerated adsorption of l-His and preferential binding was induced in ternary liposomes forming boundaries between two separate phases.
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Affiliation(s)
- Takaaki Ishigami
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| | - Atsushi Tauchi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| | - Keishi Suga
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
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Yoshimura A, Nguyen KC, Rohde GT, Saito A, Yusubov MS, Zhdankin VV. Oxidative Cycloaddition of Aldoximes with Maleimides using Catalytic Hydroxy(aryl)iodonium Species. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201600331] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Hirose M, Ishigami T, Suga K, Umakoshi H. Liposome Membrane as a Platform for the L-Pro-Catalyzed Michael Addition of trans-β-Nitrostyrene and Acetone. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:12968-12974. [PMID: 26549731 DOI: 10.1021/acs.langmuir.5b03439] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Herein, we show that the L-proline (L-Pro)-catalyzed Michael addition of trans-β-nitrostyrene and acetone can proceed in "water" using liposome membranes and that the membrane fluidity and polarity are major controlling factors for this reaction. The highest conversion and rate constant of the reaction within the liposomes was achieved with the 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)/1,2-dipalmitoyl-3-trimethylammoniumpropane (DPTAP) system. The catalytic activity of L-Pro in the liposome suspension was found to be comparable to that in a DMSO system. The reaction rate constant was found to be controlled by both the phase state of the liposome membrane and the surface charge on the membrane. Greater enantioselectivity was achieved in the presence of the liposomes than in DMSO solution, with corresponding enantiomeric excess values of 97.6% for the DOPC/DPTAP liposome system and 10% in DMSO. The hydrophobic region of the liposome membrane, which is a relatively stable self-organizing system, can serve as an effective "platform" for molecular recognition and selective conversion in aqueous media.
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Affiliation(s)
- Masanori Hirose
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Takaaki Ishigami
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Keishi Suga
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
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Characterization of the physicochemical properties of phospholipid vesicles prepared in CO2/water systems at high pressure. Biointerphases 2015; 10:031005. [DOI: 10.1116/1.4928722] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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