Chitosan-coated electrospun nanofibers with antibacterial activity

Charged nanofibers were prepared by electrospinning (ESP) poly(epsilon-caprolactone) with a copolymer bearing carboxylic acid functions. The presence of these functions allowed exposing some negative charges on the fiber surface, by dipping the fibers in a phosphate buffer. A layer of chitosan, a polycation in acidic medium, was then deposited on the nanofiber surface, thanks to electrostatic attraction. Fibers were characterized at each step of the process and the influence of the copolymer architecture on chitosan deposition was discussed. The antibacterial activity of the resulting fibers was finally assessed.