N-组氨酸壳聚糖多孔支架对牛血清白蛋白的吸附性能

Adsorption Behavior of Bovine Serum Albumin by Histidine Grafted Chitosan Porous Scaffolds

通过改变组氨酸/壳聚糖的配比及壳聚糖的相对分子质量合成了6种N-组氨酸壳聚糖(NHCS)多孔支架,考察其在模拟体液中吸附牛血清白蛋白(BSA)的能力,用紫外-可见分光光度法测定NHCS不同温度的吸附等温线和不同起始浓度下的吸附动力学曲线等。结果表明,在37.0℃、BSA的初始浓度为2.5 mg/mL时,壳聚糖的相对分子质量为50×103、组氨酸/壳聚糖的摩尔比为3∶1制得的50kD-NHCS-3多孔支架吸附BSA效果最好,吸附容量(Qe)为820.90 mg/g;吸附遵循Langmuir吸附等温式和准一级动力学方程,且是一个自发、熵增、吸热的物理吸附过程。50kD-NHCS-3多孔支架可以重复使用,有望用于BSA或其他蛋白的分离纯化。

Six type of histidine grafted chitosan （NHCS） porous scaffolds were synthesized by changing the mole ratio of histidine/chitosan and the molecular weight of the chitosan. Adsorption behavior of bovine serum albumin （BSA） by NHCS in simulated body fluid （SBF） was investigated. Ultraviolet-visible spectrophotometer was used to determine the adsorptive equilibrium curve at different initial concentrations and the adsorptive dynamic curve at different temperatures. The results indicate the adsorption capacity of 50kD-NHCS-3 （S4, Mw（CS） is 50 103, n （histidine）/n （chitosan） is 3：1） is the best of all studied NHCS porous scaffolds, the maximum adsorption capacity is 820.90 mg/g at 37.0℃, while the initial concentration of BSA solution is 2.5 mg/mL, The adsorption kinetics is in good agreement with pseudo first-order kinetic model, whereas, the adsorption isotherms could be well described by Langmuir equation. The adsorption of BSA is a spontaneous, entropy increasing, endothermic and physical process. 50kD-NHCS-3 is a good reusable matrix for adsorption and separation of BSA.