ABSTRACT
Objective To investigate the sustained release of BSA from chitosan-OREC/BSA films coated mats in vitro.Methods The negatively charged cellulose acetate (CA) fibrous mats were modified with multilayers of the positively charged chitosan or chitosan-OREC intercalated composites and the negatively charged bovine serum albumin (BSA) via electrostatic layer-by-layer (LBL) self-assembly technique.The adsorption and rinsing steps were repeated until the desired number of deposition bilayers was obtained.The in vitro BSA encapsulation and release experiments demonstrated that OREC could affect the degree of protein loading capacity and release ficiency of the LBL films coating.Results In the pH-gradient release assay,only a small amount of BSA was released from the mats in 1 h.As the time increased,the release rate of BSA of all the samples gradually went up to the maximum data within 8 h.For the samples with identical number of bilayers and record time,obvious increasing of the release amount could be seen in pH 7.4,in comparison with pH 1.2.Besides,doubling bilayers film-coated mats generally.Meanwhile,it was slightly distinguishable between 5 and 5.5 as well as 10 and 10.5 bilayers (t=0.651～ 1.324,P＞0.05).Interestingly,it could be seen that protein release of the chitosan-OREC/BSA films coated mats remarkably increased compared with that of chitosan/BSA films coated mats(t=2.264～ 2.305,P＜0.05).Conclusion The release of protein in the initial time could be controlled by adjusting the number of deposition bilayers,the outmost layer and the composition of coating bilayers.