Preparation of Polyion Complex Fibers and Capsules of DNA and Chitosan at an Aqueous Interface

Abstract

Abstract Hybrid fiber and capsule creation based on the electrostatic polynucleotide–polysaccharide interaction has been studied. The fibrous form is made from single (SS)- and double (DS)-stranded DNAs and chitosan via polyion complex (PIC) formation. When DNA solutions with and without NaCl are added to an aqueous chitosan solution without mixing, PIC films are formed at the interface. When these PIC films are withdrawn from the interface, fiber lines form in the wet states. After the intact wet fibers are dried in air, SS- and DSDNA–chitosan fibers form. The tensile strength of the strongest DSDNA–chitosan fiber is 84 MPa. The strength and the strain of the fibers depend on the NaCl concentrations of the DNA solutions. Stable SS- and DSDNA–chitosan PIC capsules can also be prepared.