HEMA-grafted chitosan for dialysis membrane applications

Chitosan was graft copolymerized with HEMA (2‐Hydroxyethylmethacrylate) for the development of blood‐compatible dialysis membranes. The permeation characteristics of HEMA‐grafted chitosan films for four different solutes creatinine, urea, glucose, and albumin was studied in vitro at 37°C for assessment of the suitability as dialysis membranes. The grafted film CH‐12.5 composition (425% grafting) showed very high permeation to creatinine by reaching the equilibrium within 45 min. The compositions CH‐7.5 and CH‐12.5 showed excellent permeation to glucose when compared to virgin chitosan films. In the case of urea permeation, all the grafted compositions exhibited higher percent permeation than the virgin chitosan films. The copolymer films CH‐7.5 and CH‐12.5 showed enhanced permeability for the high molecular weight solute, albumin. The other grafted copolymer compositions followed almost the same trend as that of chitosan for the low molecular weight solutes as well as the high molecular weight solute. The copolymer films were also found to be highly blood compatible, noncytotoxic, and biodegradable. Hence, the need for developing blood‐compatible chitosan membranes with desirable permeability properties is achieved by the graft copolymerization of HEMA onto chitosan. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2960–2966, 2006