Composite contact of binary lipid membranes

• Published in: The European physical journal. E, Soft matter and biological physics Soft matter and biological physics, 2013-08, Vol.36 (8), p.89-89, Article 89
• Main Authors: Jelerčič, U., Ziherl, P.
• Format: Article
• Language: English
• Subjects: Biological and Medical Physics; Biophysics; Chemistry; Colloidal state and disperse state; Complex Fluids and Microfluidics; Complex Systems; Elastic Modulus; Exact sciences and technology; General and physical chemistry; Lipid Bilayers - chemistry; Lipids - chemistry; Membranes; Micelles; Nanotechnology; Physics; Physics and Astronomy; Polymer Sciences; Regular Article; Soft and Granular Matter; Surfaces and Interfaces; Thin Films; Unilamellar Liposomes - chemistry
• ISSN: 1292-8941; 1292-895X
• DOI: 10.1140/epje/i2013-13089-8

Upon adhesion, binary lipid membranes may retain their structural identity but they may also undergo partial fusion promoted by microscopic phase separation of the components. In membranes composed of cylindrical and inverted conical lipids, a partially fused contact zone may consist of inverted micelles sandwiched between two monolayers. We theoretically analyze the elastic properties of such a composite contact zone. We calculate its bending moduli and we show that they may be considerably larger than the moduli of a phase-nonseparated double bilayer. The main mechanism responsible for the enhanced rigidity of the composite contact structure is the increased separation of the two monolayers caused by the presence of water in the inverted micelles. Graphical abstract