Partition of several model bioproducts in recycling aqueous two-phase systems with pH/light responsive copolymers

Aqueous two-phase systems (ATPSs) are attractive bioseparation techniques. However, the phase-forming polymers could not be effectively recycled due to high cost and environmental problems. In this study, a new recycling aqueous two-phase system (ATPS) composed of a light-responsive copolymer (PNNC) and a pH-responsive copolymer (PADB) was applied to bioseparation. BSA, lysozyme, L-Tyr and tryptophane could be effectively enriched into one phase of the ATPS, with partition coefficients of 10.2, 0.11, 0.12 and 6.3, respectively. Trypsin was purified from its crude material by using the PNNC/PADB ATPS, with 92.3% of activity recovery, and 6.6-fold purification factor. PNNC and PADB were recycled with recovery of 96–99% in four runs, and did not disturb partition behavior of trypsin from crude material in recycling systems. The recyclable PNNC–PADB ATPSs show potential application.

Figure optionsDownload as PowerPoint slideResearch highlights▶ A new recycling aqueous two-phase systems (ATPS) composed of a light-responsive copolymer (PNNC) and a pH-responsive copolymer (PADB) was applied to bioseparation. ▶ BSA, Lysozyme, L-Tyr and Tryptophane could be effectively enriched into one phase of the ATPS, with partition coefficients of 10.2, 0.11, 0.12 and 6.3, respectively. ▶ Trypsin was purified from its crude material by using the PNNC/PADB ATPS. ▶ PNNC and PADB were recycled with recovery of 96-99% in four repeated runs. The ATPS show potential application.