Title:	Studies on the mechanical properties and phase behavior of lipid bilayers in the presence of some alcohols and oxysterols
Authors:	Buti, Suryabrahmam
Thesis Advisor:	Raghunathan, V.A.
Subject:	Soft condensed matter
Issue Date:	2-May-2022
Publisher:	Raman Research Institute, Bangalore.
Citation:	Ph.D. Thesis, Jawaharlal Nehru University, New Delhi, 2022
Abstract:	Lipid bilayers are present in different parts of a cell, such as the plasma membrane, nuclear membrane, endoplasmic reticulum, Golgi apparatus and vacuole. They are involved in a variety of processes like endocytosis, exocytosis, cell fusion and fission. In order to understand their function, it is essential to know their physical properties and their interaction with other molecules. To reduce the complexity of the system, studies are often conducted on model membranes made up of a few lipids. This thesis deals with the mechanical properties, structure and phase behaviour of lipid bilayers in the presence of short and medium-chain length alcohols and oxysterols. Experimental studies presented in this thesis can be divided into two parts. The first part is related to the mechanical properties of lipid bilayers. Towards this, we have implemented and employed the vesicle fluctuation analysis (VFA) technique to obtain bending rigidity of membranes. The influence of short and medium-chain alcohols on bending rigidity and thickness of bilayers in the fluid phase has been studied using VFA and X-ray scattering techniques, respectively. In the second part, I will discuss a novel fluid-fluid phase coexistence region induced in two-component lipid membranes. We have studied the influence of 1-decanol on the phase behaviour of DMPC bilayers and have found a narrow region of fluid-fluid coexistence between the fluid and gel phases. I have also observed tension-induced fluid-fluid coexistence in POPC membranes in the presence of a cholesterol derivative. In this study, tension is varied either by micropipette aspiration technique or by applying an osmotic pressure.
Description:	Restricted Access
URI:	http://hdl.handle.net/2289/7980
Copyright:	This thesis is posted here with the permission of the author. Personal use of this material is permitted. Any other use requires prior permission of the author. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.
Appears in Collections:	Theses (SCM)

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