藻蓝蛋白静态吸附平衡及热力学研究

摘要

研究了钝顶螺旋藻中藻蓝蛋白在DEAE-Sephadex A-50离子交换树脂上的静态吸附平衡,考察了无机盐NaCl浓度和聚合物PEG6000质量分数,以及吸附温度对藻蓝蛋白静态吸附平衡的影响,以Langmuir和Freundlich吸附等温方程分别对不同条件下的吸附平衡数据进行拟合,并计算出吸附过程的热力学参数△G,△H和△S.研究表明:NaCl具有显著抑制藻蓝蛋白吸附的作用,而PEG具有明显促进藻蓝蛋白吸附的作用；Freundlich吸附等温方程对藻蓝蛋白的吸附平衡数据具有更好的拟合效果,并判定吸附过程为优惠吸附；在不同的吸附条件下,AG ＜0,且其绝对值小于20 k J/mol,表明吸附过程可自发进行并为物理吸附,△H＞O,表明该吸附过程为吸热过程,△S＞0,该吸附过程属于熵增过程.%The adsorption equilibrium of c-phycocyanin from Spirulina platensis on DEAE-Sephadex A-SO was studied. The effects of NaCl concentration and polymer PEG6000 mass fraction, and adsorption temperature on the adsorption equilibrium of c-phycocyanin were investigated. The adsorption data were fitted to the Langmuir and Freundlich equations, and the thermodynamic parameters such as AG, Aif and AS were calculated. The results imply that NaCl can decrease the adsorption while PEC can increase the adsorption. The experimental data can be well fitted by Freundlich equations and the adsorption is verified to be the optimal adsorption. Under the various adsorption conditions, Gibbs free energy change △G<0, its absolute value is less than 20 kJ/mol, showing that the adsorption process is spontaneous and physical adsorption. The enthalpy change △H>0 indicates that the process is endothermic and physical adsorption. The entropy change △S>0 indicates that the adsorption is an entropic increasing process.