超声波对PEG/磷酸盐双水相系统组成及BSA分配的影响

超声波有望强化双水相萃取分离过程。本文研究了超声波对聚乙二醇(PEG)/磷酸盐双水相系统(ATPS)组成及牛血清白蛋白(BSA)在其中分配的变化规律。在超声波作用下,由于PEG6000的分子量增大,引起PEG600010%(w/w)/PO43-6%(w/w)ATPS在混合过程的Gibbs自由能变化增大,所形成的两相间差别变大,相图节线变长;而且,PEG分子量增大改变了BSA在双水相系统的静电作用和盐析作用,超声波作用提高了BSA在ATPS上相中的含量,增大了分配系数,减少了下相分配率。

Effect of ultrasonic wave on phase constitution of and BSA partitioning in the PEG/ phosphate aqueous two-phase system

Ultrasonic irradiation is expected to enhance the aqueous two-phase extraction.The effect of ultrasonic wave on the phase composition of and the partitioning of BSA in PEG/ phosphate aqueous two-phase system (ATPS) is studied.Under the irradiation of ultrasound, the tie-line length of PEG 6000 10% (w/w)/ PO43-6% (w/w) ATPS increases due to the increase in the PEG molecular weight, indicating that the difference between the top phase and the bottom phase increases.Moreover, the partition of BSA in the top phase of ATPS will be increased due to the change in electrostatic interaction and salt-out interaction, which are caused by the increase in the PEG molecular weight in the ultrasonic field, the BSA partition coefficient between the top phase and the bottom phase increases, and the fraction of BSA in the bottom phase decrease consequently.