Chitosan/bovine serum albumin ultrathin films studied by radio-labeled method

Chitosan/bovine serum albumin (BSA) ultrathin films were fabricated on modified quartz wafer through layer by layer deposition.The effects of experimental conditions, such as pH value, molecular weight of CS, ionic strength and polyanions coexisting in BSA solution, on the fabrication and the stab...Chitosan/bovine serum albumin (BSA) ultrathin films were fabricated on modified quartz wafer through layer-by-layer deposition. The effects of experimental conditions, such as pH value, molecular weight of CS, ionic strength and polyanions coexisting in BSA solution, on the fabrication and the stability of films were investigated with a radio-labeled method. The results show that the absorbed BSA is almost proportional to the number of assembly cycle except the first 2 cycles, and chitosan/BSA films are favorable to be fabricated in chitosan aq AcOH at pH = 5. 2 as compared with at pH = 1.0. When two different molecular weight ( MW) chitosans were used (Meta approximate to1.2 x 10(5), Meta approximate to 1.0 x 10(6)), the lower MW chitosan adsorbs more BSA, but less stable ultrathin films are fabricated. Similar results were obtained that the amount of adsorbed BSA is higher but the films formed are less stable in water than in phosphate-buffered saline (PBS). The adsorption of BSA is restricted greatly in the presence of poly(sodium styrene-sulfonate) (PSS) mainly because of the competitive adsorption.SCI(E)中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)401116-11