Structural States of Self-Assembled Lamellar DNA-Membrane Templates During Artificial Biomineralization of CdS Nanorods

摘要

Self-assembled complexes comprised of anionic polyelectrolytes and cationic lipids have recently received intense experimental and theoretical attention. In this preprint, we examine CdS growth within self-assembled lamellar DNA-membrane templates, a simple prototypical biomineralization system in which the structures, charge distributions, and phase behavior of the components can be controlled precisely. DNA-membrane complexes were originally conceived as non-viral gene delivery systems. The addition of DNA to cationic liposomes induces a topological transition from liposomes to condensed, birefringent liquid crystalline globules with a novel multi-lamellar structure, in which a periodic one-dimensional (1D) lattice of parallel DNA chains is confined between stacked two-dimensional (2D) lipid sheets.1 The interhelical distance between DNA chains in the 1D lattice intercalated between the lamellar membrane sheets can be tuned between 2.5-6.0 nm by changing the relative proportion of cationic and neutral lipids.