DNA gel particles from single and double-tail surfactants: supramolecular assemblies and release characteristics

Abstract

Cationic surfactants with one alkyl chain have offered a particularly efficient control of the properties of DNA-based particles. However, most transfection lipids do not form micelles as single-chain surfactants. In this work, the formation of DNA gel particles mixing DNA (either single- (ssDNA) or double-stranded (dsDNA)) with the vesicle-forming double chain surfactant didodecyldimethylammonium bromide (DDAB) is described. For comparative purposes, the formation of DNA gel particles using the single chain surfactant dodecyltrimethylammonium bromide (DTAB) has been investigated. Results on the encapsulation of DNA and its release are strongly dependent on the surfactant structure. DDAB–DNA gel particles have been shown to form ordered multi-vesicular assemblies which resemble the architecture of biological tissues. The characteristic sizes and shapes of the resulting structures strongly depend on the secondary structure of the DNA. Some features about the DNA–vesicle interaction involved in these particles have been deduced from direct optical, fluorescence and electron microscopy observations.