The copper (Ⅱ) complex fibers were prepared by heterogeneous coordination replacement reaction of silk fibroin

viscose cellulose and poly(vinyl alcohol)(PVA) fiber in cuprammonium solution.The coordination structures of the fiber were studied by ESR spectra etc.The antibacterial experiment shows that the antibacterial activities of these three copper (Ⅱ) complex fibers are in the following order:Cu2+ PVA fiber >Cu2+ Cellulose fiber >Cu2+ Silk fibroin fiber.It is verified that the antibacterial activity is related with stability of the coordination structure of the copper(Ⅱ) complex fiber.That is the more unstable coordination structure

the better the antibacterial activity.A copper (Ⅱ) complex fiber of citric acid modified cellulose (Cu2+-CA-Cellulose) with moderate stability of the coordination structure which has been designed shows good antibacterial activity and washing fastness

as expectd.