title: Preservation of Supported Lipid Membrane Integrity from Thermal Disruption: Osmotic Effect.
abstract: Preservation of structural integrity under various environmental conditions is one major concern in the development of the supported lipid membrane (SLM)-based devices. It is common for SLMs to experience temperature shifts from manufacture, processing, storage, and transport to operation. In this work, we studied the thermal adaption of the supported membranes on silica substrates. Homogenous SLMs with little defects were formed through the vesicle fusion method. The mass and fluidity of the bilayers were found to deteriorate from a heating process but not a cooling process. Fluorescence characterizations showed that the membranes initially budded as a result of heating-induced lipid lateral area expansion, followed by the possible fates including maintenance, retraction, and fission, among which the last contributes to the irreversible compromise of the SLM integrity and spontaneous release of the interlipid stress accumulated. Based on the mechanism, we developed a strategy to protect SLMs from thermal disruption by increasing the solute concentration in medium. An improved preservation of the membrane mass and fluidity against the heating process was observed, accompanied by a decrease in the retraction and fission of the buds. Theoretical analysis revealed a high osmotic energy penalty for the fission, which accounts for the depressed disruption. This osmotic-based protection strategy is facile, solute nonspecific, and long-term efficient and has little impact on the original SLM properties. The results may help broaden SLM applications and sustain the robustness of SLM-based devices under multiple thermal conditions.
authors.affiliation: Collaborative Innovation Center of Advanced Microstructures and Department of Physics, Nanjing University , Nanjing 210093, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhu
authors.affiliation: School of Electronics and Information Engineering, Yi Li Normal University , Yining 835000, China.|Laboratory of Solid State Microstructures, Nanjing University , Nanjing 210093, China.
authors.forename: Zhongying
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: Collaborative Innovation Center of Advanced Microstructures and Department of Physics, Nanjing University , Nanjing 210093, China.|Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University , Suzhou 215006, China.
authors.forename: Yuqiang
authors.initials: Y
authors.lastname: Ma
authors.affiliation: College of Engineering and Applied Sciences, Nanjing University , Nanjing 210093, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Hu
mesh_terms: D000067493:Dynamic Light Scattering; D008051:Lipid Bilayers / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009995:Osmosis; D058525:Quartz Crystal Microbalance Techniques; D012965:Sodium Chloride / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics
chemical_list: D008051:Lipid Bilayers; D012965:Sodium Chloride
keywords: fission; fluidity; lipid lateral area; osmotic stress; supported lipid membrane; thermal stability