Synthesis of two thermo-responsive copolymers forming recyclable aqueous two-phase systems and its application in cefprozil partition

Aqueous two-phase systems are efficient purification methods for bioproducts. However, recovery difficulty of the copolymers forming aqueous two-phase systems becomes obstacle in scale-up application. In the study, novel recyclable aqueous two-phase systems have been developed by using two thermo-responsive copolymers, P NE and P VAm . Copolymer P NE was copolymerized by using N-isopropylacrylamide and ethyl methacrylate as monomers, and P VAm was synthesized by using N-vinylcaprolactam and acrylamide as monomers. The lower critical solution temperatures of P NE and P VAm are 28.7   °C and 35.6   °C, respectively. The recoveries of both polymers can reach over 95%. The minimal and maximal partition coefficient of cefprozil was 0.33 at 50   mM NH 4 F and 6.55 at 70   mM LiCl. Two empirical equations were used to correlate with experimental binodal curve. Partition coefficients of cefprozil examined in the ATPS were correlated with tie-line length and calculated partition coefficient.