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Yoon BK, Tan SW, Tan JYB, Jackman JA, Cho NJ. Nanoarchitectonics-based model membrane platforms for probing membrane-disruptive interactions of odd-chain antimicrobial lipids. NANO CONVERGENCE 2022; 9:48. [PMID: 36318349 PMCID: PMC9626702 DOI: 10.1186/s40580-022-00339-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
The use of nanoscience tools to investigate how antimicrobial lipids disrupt phospholipid membranes has greatly advanced molecular-level biophysical understanding and opened the door to new application possibilities. Until now, relevant studies have focused on even-chain antimicrobial lipids while there remains an outstanding need to investigate the membrane-disruptive properties of odd-chain antimicrobial lipids that are known to be highly biologically active. Herein, using the quartz crystal microbalance-dissipation (QCM-D) and electrochemical impedance spectroscopy (EIS) techniques, we investigated how an 11-carbon, saturated fatty acid and its corresponding monoglyceride-termed undecanoic acid and monoundecanoin, respectively-disrupt membrane-mimicking phospholipid bilayers with different nanoarchitectures. QCM-D tracking revealed that undecanoic acid and monoundecanoin caused membrane tubulation and budding from supported lipid bilayers, respectively, and were only active above their experimentally determined critical micelle concentration (CMC) values. Monoundecanoin was more potent due to a lower CMC and electrochemical impedance spectroscopy (EIS) characterization demonstrated that monoundecanoin caused irreversible membrane disruption of a tethered lipid bilayer platform at sufficiently high compound concentrations, whereas undecanoic acid only induced transient membrane disruption. This integrated biophysical approach also led us to identify that the tested 11-carbon antimicrobial lipids cause more extensive membrane disruption than their respective 12-carbon analogues at 2 × CMC, which suggests that they could be promising molecular components within next-generation antimicrobial nanomedicine strategies.
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Affiliation(s)
- Bo Kyeong Yoon
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- School of Healthcare and Biomedical Engineering, Chonnam National University, Yeosu, 59626, Republic of Korea
| | - Sue Woon Tan
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jia Ying Brenda Tan
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Joshua A Jackman
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon, 16419, Republic of Korea.
| | - Nam-Joon Cho
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
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2
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Biophysical Characterization of LTX-315 Anticancer Peptide Interactions with Model Membrane Platforms: Effect of Membrane Surface Charge. Int J Mol Sci 2022; 23:ijms231810558. [PMID: 36142470 PMCID: PMC9501188 DOI: 10.3390/ijms231810558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 09/06/2022] [Accepted: 09/08/2022] [Indexed: 11/16/2022] Open
Abstract
LTX-315 is a clinical-stage, anticancer peptide therapeutic that disrupts cancer cell membranes. Existing mechanistic knowledge about LTX-315 has been obtained from cell-based biological assays, and there is an outstanding need to directly characterize the corresponding membrane-peptide interactions from a biophysical perspective. Herein, we investigated the membrane-disruptive properties of the LTX-315 peptide using three cell-membrane-mimicking membrane platforms on solid supports, namely the supported lipid bilayer, intact vesicle adlayer, and tethered lipid bilayer, in combination with quartz crystal microbalance-dissipation (QCM-D) and electrochemical impedance spectroscopy (EIS) measurements. The results showed that the cationic LTX-315 peptide selectively disrupted negatively charged phospholipid membranes to a greater extent than zwitterionic or positively charged phospholipid membranes, whereby electrostatic interactions were the main factor to influence peptide attachment and membrane curvature was a secondary factor. Of note, the EIS measurements showed that the LTX-315 peptide extensively and irreversibly permeabilized negatively charged, tethered lipid bilayers that contained high phosphatidylserine lipid levels representative of the outer leaflet of cancer cell membranes, while circular dichroism (CD) spectroscopy experiments indicated that the LTX-315 peptide was structureless and the corresponding membrane-disruptive interactions did not involve peptide conformational changes. Dynamic light scattering (DLS) measurements further verified that the LTX-315 peptide selectively caused irreversible disruption of negatively charged lipid vesicles. Together, our findings demonstrate that the LTX-315 peptide preferentially disrupts negatively charged phospholipid membranes in an irreversible manner, which reinforces its potential as an emerging cancer immunotherapy and offers a biophysical framework to guide future peptide engineering efforts.
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Di Leone S, Kyropoulou M, Köchlin J, Wehr R, Meier WP, Palivan CG. Tailoring a Solvent-Assisted Method for Solid-Supported Hybrid Lipid-Polymer Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:6561-6570. [PMID: 35580858 PMCID: PMC9161443 DOI: 10.1021/acs.langmuir.2c00204] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/11/2022] [Indexed: 06/15/2023]
Abstract
Combining amphiphilic block copolymers and phospholipids opens new opportunities for the preparation of artificial membranes. The chemical versatility and mechanical robustness of polymers together with the fluidity and biocompatibility of lipids afford hybrid membranes with unique properties that are of great interest in the field of bioengineering. Owing to its straightforwardness, the solvent-assisted method (SA) is particularly attractive for obtaining solid-supported membranes. While the SA method was first developed for lipids and very recently extended to amphiphilic block copolymers, its potential to develop hybrid membranes has not yet been explored. Here, we tailor the SA method to prepare solid-supported polymer-lipid hybrid membranes by combining a small library of amphiphilic diblock copolymers poly(dimethyl siloxane)-poly(2-methyl-2-oxazoline) and poly(butylene oxide)-block-poly(glycidol) with phospholipids commonly found in cell membranes including 1,2-dihexadecanoyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine, sphingomyelin, and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(glutaryl). The optimization of the conditions under which the SA method was applied allowed for the formation of hybrid polymer-lipid solid-supported membranes. The real-time formation and morphology of these hybrid membranes were evaluated using a combination of quartz crystal microbalance and atomic force microscopy. Depending on the type of polymer-lipid combination, significant differences in membrane coverage, formation of domains, and quality of membranes were obtained. The use of the SA method for a rapid and controlled formation of solid-supported hybrid membranes provides the basis for developing customized artificial hybrid membranes.
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Affiliation(s)
- Stefano Di Leone
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- School
of Life Sciences, Institute for Chemistry and Bioanalytics, University of Applied Sciences Northwestern Switzerland
(FHNW), Grundenstrasse
40, 4132 Muttenz, Switzerland
| | - Myrto Kyropoulou
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- National
Centre of Competence in Research Molecular Systems Engineering (NCCR
MSE), BPR 1095, Mattenstrasse
24a, 4058 Basel, Switzerland
| | - Julian Köchlin
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Riccardo Wehr
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Wolfgang P. Meier
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- National
Centre of Competence in Research Molecular Systems Engineering (NCCR
MSE), BPR 1095, Mattenstrasse
24a, 4058 Basel, Switzerland
| | - Cornelia G. Palivan
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- National
Centre of Competence in Research Molecular Systems Engineering (NCCR
MSE), BPR 1095, Mattenstrasse
24a, 4058 Basel, Switzerland
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Xu H, Tae H, Cho NJ, Huang C, Hsia KJ. Thermodynamic Modeling of Solvent-Assisted Lipid Bilayer Formation Process. MICROMACHINES 2022; 13:mi13010134. [PMID: 35056299 PMCID: PMC8777629 DOI: 10.3390/mi13010134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/10/2022] [Accepted: 01/11/2022] [Indexed: 12/22/2022]
Abstract
The solvent-assisted lipid bilayer (SALB) formation method provides a simple and efficient, microfluidic-based strategy to fabricate supported lipid bilayers (SLBs) with rich compositional diversity on a wide range of solid supports. While various studies have been performed to characterize SLBs formed using the SALB method, relatively limited work has been carried out to understand the underlying mechanisms of SALB formation under various experimental conditions. Through thermodynamic modeling, we studied the experimental parameters that affect the SALB formation process, including substrate surface properties, initial lipid concentration, and temperature. It was found that all the parameters are critically important to successfully form high-quality SLBs. The model also helps to identify the range of parameter space within which conformal, homogeneous SLBs can be fabricated, and provides mechanistic guidance to optimize experimental conditions for lipid membrane-related applications.
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Affiliation(s)
- Hongmei Xu
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore;
| | - Hyunhyuk Tae
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore;
| | - Nam-Joon Cho
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore;
- Correspondence: (N.-J.C.); (C.H.); (K.J.H.)
| | - Changjin Huang
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore;
- Correspondence: (N.-J.C.); (C.H.); (K.J.H.)
| | - K. Jimmy Hsia
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore;
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Correspondence: (N.-J.C.); (C.H.); (K.J.H.)
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Di Leone S, Vallapurackal J, Yorulmaz Avsar S, Kyropolou M, Ward TR, Palivan CG, Meier W. Expanding the Potential of the Solvent-Assisted Method to Create Bio-Interfaces from Amphiphilic Block Copolymers. Biomacromolecules 2021; 22:3005-3016. [PMID: 34105950 DOI: 10.1021/acs.biomac.1c00424] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Artificial membranes, as materials with biomimetic properties, can be applied in various fields, such as drug screening or bio-sensing. The solvent-assisted method (SA) represents a straightforward method to prepare lipid solid-supported membranes. It overcomes the main limitations of established membrane preparation methods, such as Langmuir-Blodgett (LB) or vesicle fusion. However, it has not yet been applied to create artificial membranes based on amphiphilic block copolymers, despite their enhanced mechanical stability compared to lipid-based membranes and bio-compatible properties. Here, we applied the SA method on different amphiphilic di- and triblock poly(dimethylsiloxane)-block-poly(2-methyl-2-oxazoline) (PDMS-b-PMOXA) copolymers and optimized the conditions to prepare artificial membranes on a solid support. The real-time membrane formation, the morphology, and the mechanical properties have been evaluated by a combination of atomic force microscopy and quartz crystal microbalance. Then, selected biomolecules including complementary DNA strands and an artificial deallylase metalloenzyme (ADAse) were incorporated into these membranes relying on the biotin-streptavidin technology. DNA strands served to establish the capability of these synthetic membranes to interact with biomolecules by preserving their correct conformation. The catalytic activity of the ADAse following its membrane anchoring induced the functionality of the biomimetic platform. Polymer membranes on solid support as prepared by the SA method open new opportunities for the creation of artificial membranes with tailored biomimetic properties and functionality.
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Affiliation(s)
- Stefano Di Leone
- Chemistry Department, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland.,School of Life Sciences, Institute for Chemistry and Bioanalytics, University of Applied Sciences Northwestern Switzerland (FHNW), Grundenstrasse 40, 4132 Muttenz, Switzerland
| | - Jaicy Vallapurackal
- Chemistry Department, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Saziye Yorulmaz Avsar
- Chemistry Department, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Myrto Kyropolou
- Chemistry Department, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Thomas R Ward
- Chemistry Department, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Cornelia G Palivan
- Chemistry Department, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Wolfgang Meier
- Chemistry Department, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
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Jackman JA, Cho NJ. Supported Lipid Bilayer Formation: Beyond Vesicle Fusion. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:1387-1400. [PMID: 31990559 DOI: 10.1021/acs.langmuir.9b03706] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Supported lipid bilayers (SLBs) are cell-membrane-mimicking platforms that can be formed on solid surfaces and integrated with a wide range of surface-sensitive measurement techniques. SLBs are useful for unravelling details of fundamental membrane biology and biophysics as well as for various medical, biotechnology, and environmental science applications. Thus, there is high interest in developing simple and robust methods to fabricate SLBs. Currently, vesicle fusion is a popular method to form SLBs and involves the adsorption and spontaneous rupture of lipid vesicles on a solid surface. However, successful vesicle fusion depends on high-quality vesicle preparation, and it typically works with a narrow range of material supports and lipid compositions. In this Feature Article, we summarize current progress in developing two new SLB fabrication techniques termed the solvent-assisted lipid bilayer (SALB) and bicelle methods, which have compelling advantages such as simple sample preparation and compatibility with a wide range of material supports and lipid compositions. The molecular self-assembly principles underpinning the two strategies and important experimental parameters are critically discussed, and recent application examples are presented. Looking forward, we envision that these emerging SLB fabrication strategies can be widely adopted by specialists and nonspecialists alike, paving the way to enriching our understanding of lipid membrane properties and realizing new application possibilities.
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Affiliation(s)
- Joshua A Jackman
- School of Chemical Engineering , Sungkyunkwan University , Suwon 16419 , Republic of Korea
| | - Nam-Joon Cho
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , Singapore 639798 , Singapore
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Su Z, Juhaniewicz-Debinska J, Sek S, Lipkowski J. Water Structure in the Submembrane Region of a Floating Lipid Bilayer: The Effect of an Ion Channel Formation and the Channel Blocker. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:409-418. [PMID: 31815479 DOI: 10.1021/acs.langmuir.9b03271] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The structure of water in the submembrane region of the bilayer of DPhPC floating (fBLM) on a monolayer of 1-thio-β-d-glucose (β-Tg)-modified gold nanoparticle film was studied by the surface-enhanced infrared absorption spectroscopy (SEIRAS). SEIRAS employs surface enhancement of the mean square electric field of the photon, which is acting on a few molecular layers above the film of gold nanoparticles. Therefore, it is uniquely suited to probe water molecules in the submembrane region and provides unique information concerning the structure of the hydrogen bond network of water surrounding the lipid bilayer. The IR spectra indicated that water with a strong hydrogen network is separating the membrane from the gold surface. This water is more ordered than the water in the bulk. When alamethicin, a peptide forming ion channels, is inserted into the membrane, the network is only slightly loosened. The addition of amiloride, an ion channel blocker, results in a significant decrease in the amount of water in the submembrane region. The remaining water has a significantly distorted hydrogen bond network. This study provides unique information about the effect of the ion channel on water transport across the bilayer. The electrode potential has a relatively small effect on water structure in the submembrane region. However, the IR studies demonstrated that water is less ordered at positive transmembrane potentials. The present results provide significant insight into the nature of hydration of a floating lipid bilayer on the gold electrode surface.
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Affiliation(s)
- ZhangFei Su
- Department of Chemistry , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
| | - Joanna Juhaniewicz-Debinska
- Faculty of Chemistry, Biological and Chemical Research Centre , University of Warsaw , Żwirki i Wigury 101 , 02-089 Warsaw , Poland
| | - Slawomir Sek
- Department of Chemistry , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
- Faculty of Chemistry, Biological and Chemical Research Centre , University of Warsaw , Żwirki i Wigury 101 , 02-089 Warsaw , Poland
| | - Jacek Lipkowski
- Department of Chemistry , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
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Sut TN, Park S, Choe Y, Cho NJ. Characterizing the Supported Lipid Membrane Formation from Cholesterol-Rich Bicelles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:15063-15070. [PMID: 31670521 DOI: 10.1021/acs.langmuir.9b02851] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Supported lipid bilayers (SLBs) are simplified model membrane systems that mimic the fundamental properties of biological cell membranes and allow the surface-sensitive tools to be used in numerous sensing applications. SLBs can be prepared by various methods including vesicle fusion, solvent-assisted lipid bilayer (SALB), and bicelle adsorption and are generally composed of phospholipids. Incorporating other biologically relevant molecules, such as cholesterol (Chol), into SLBs has been reported with the vesicle fusion and SALB methods, whereas it remains unexplored with the bicelle absorption method. Herein, using the quartz crystal microbalance-dissipation (QCM-D) and fluorescence microscopy techniques, we explored the possibility of forming SLBs from Chol-containing bicelles and discovered that Chol-enriched SLBs can be fabricated with bicelles. We also compared the Chol-enriched SLB formation of the bicelle method to that of vesicle fusion and SALB and discussed how the differences in lipid assembly properties can cause the differences in the adsorption kinetics and final results of SLB formation. Collectively, our findings demonstrate that the vesicle fusion method is least favorable for forming Chol-enriched SLBs, whereas the SALB and bicelle methods are more favorable, highlighting the need to consider the application requirements when choosing a suitable method for the formation of Chol-enriched SLBs.
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Affiliation(s)
- Tun Naw Sut
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
| | - Soohyun Park
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
| | - Younghwan Choe
- Department of Chemistry , Columbia University , 3000 Broadway , New York 10027 , United States
| | - Nam-Joon Cho
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
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Chin H, Gillissen JJJ, Miyako E, Cho NJ. Microfluidic liquid cell chamber for scanning probe microscopy measurement application. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:046105. [PMID: 31043033 DOI: 10.1063/1.5086063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 03/25/2019] [Indexed: 06/09/2023]
Abstract
In this paper, we present a universal microfluidic liquid chamber device platform for atomic force microscopy (AFM), which enables to fabricate the uniform lipid bilayer on the hydrophilic surface using the solvent-assisted lipid bilayer formation method. Using this device enables us to acquire the various properties of delicate soft matter, including morphological data, and mechanical property measurements, using high-resolution AFM systems. The proposed technology is expected to provide an understanding of complicated biological materials.
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Affiliation(s)
- Hokyun Chin
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798
| | - Jurriaan J J Gillissen
- Department of Mathematics, University College London, Gower Street, Bloomsbury, London WC1E 6BT, United Kingdom
| | - Eijiro Miyako
- Nanomaterials Research Institute (NMRI), National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Nam-Joon Cho
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798
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Valle-González ER, Jackman JA, Yoon BK, Park S, Sut TN, Cho NJ. Characterizing How Acidic pH Conditions Affect the Membrane-Disruptive Activities of Lauric Acid and Glycerol Monolaurate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:13745-13753. [PMID: 30343569 DOI: 10.1021/acs.langmuir.8b02536] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Fatty acids and monoglycerides are single-chain lipid amphiphiles that interact with phospholipid membranes as part of various biological activities. For example, they can exhibit membrane-disruptive behavior against microbial pathogens on the human skin surface. Supported lipid bilayers (SLBs) provide a useful experimental platform to characterize these membrane-disruptive behaviors, although related studies have been limited to neutral pH conditions. Herein, we investigated how lauric acid (LA) and glycerol monolaurate (GML) interact with SLBs and cause membrane morphological changes under acidic pH conditions that are representative of the human skin surface. Although LA induces tubule formation under neutral pH conditions, we discovered that LA causes membrane phase separation under acidic pH conditions. By contrast, GML induced membrane budding in both pH environments, although there was more extensive membrane remodeling under acidic pH conditions. We discuss these findings in the context of how solution pH affects the ionization states and micellar aggregation properties of LA and GML as well as its effect on the bending stiffness of lipid bilayers. Collectively, the findings demonstrate that solution pH plays an important role in modulating the interaction of fatty acids and monoglycerides with phospholipid membranes, and hence influences the scope and potency of their membrane-disruptive activities.
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Affiliation(s)
- Elba R Valle-González
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 50 Nanyang Drive , 637553 , Singapore
| | - Joshua A Jackman
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 50 Nanyang Drive , 637553 , Singapore
| | - Bo Kyeong Yoon
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 50 Nanyang Drive , 637553 , Singapore
| | - Soohyun Park
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 50 Nanyang Drive , 637553 , Singapore
| | - Tun Naw Sut
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 50 Nanyang Drive , 637553 , Singapore
| | - Nam-Joon Cho
- School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 50 Nanyang Drive , 637553 , Singapore
- School of Chemical and Biomedical Engineering , Nanyang Technological University , 62 Nanyang Drive , 637459 , Singapore
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