title: Synthesis of thermo-responsive polymers recycling aqueous two-phase systems and phase formation mechanism with partition of ε-polylysine.
abstract: Aqueous two-phase systems (ATPS) have the potential application in bioseparation and biocatalysis engineering. In this paper, a recyclable ATPS was developed by two thermo-responsive copolymers, PVBAmand PN. Copolymer PVBAmwas copolymerized using N-vinylcaprolactam, Butyl methacrylate and Acrylamide as monomers, and PNwas synthesized by N-isopropylacrylamide. The lower critical solution temperature (LCST) of PVBAmand PNwere 45.0°C and 33.5°C, respectively. The recoveries of both polymers could achieve over 95.0%. The phase behavior and formation mechanism of PVBAm/PNATPS was studied. Low-field nuclear magnetic resonance (LF-NMR) was applied in the phase-forming mechanism study in ATPS. In addition, combining the analysis results of surface tension, transmission electron microscopy and dynamic light scattering, the phase-forming of the PVBAm/PNATPS was proved. The application was performed by partition of ε-polylysine in the 2% PVBAm/2% PN(w/w) ATPS. The results demonstrated that ε-polylysine was extracted into the PN-rich phase, the maximal partition coefficient (1/K) and extraction recovery of pure ε-polylysine were 6.87 and 96.36%, respectively, and 7.41 partition coefficient and 97.85% extraction recovery for ε-polylysine fermentation broth were obtained in the presence of 50mM (NH4)2SO4at room temperature. And this method can effectively remove the most impurities from fermentation broth when (NH4)2SO4exists in the ATPS. It is believed that the thermo-responsive recycling ATPS has a good application prospect in the field of bio-separation.
authors: State Key Laboratory of Bioreactor Engineering, Department of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China.
authors: Chengning
authors: C
authors: Xu
authors: State Key Laboratory of Bioreactor Engineering, Department of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China.
authors: Wenying
authors: W
authors: Dong
authors: State Key Laboratory of Bioreactor Engineering, Department of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China. Electronic address: wanjunfen@ecust.edu.cn.
authors: Junfen
authors: J
authors: Wan
authors: State Key Laboratory of Bioreactor Engineering, Department of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China. Electronic address: caoxj@ecust.edu.cn.
authors: Xuejun
authors: X
authors: Cao
mesh_terms: D020106:Acrylamide / Q000737:chemistry; D000178:Acrylamides / Q000737:chemistry; D002209:Caprolactam / Q000031:analogs & derivatives / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008689:Methacrylates / Q000737:chemistry; D011107:Polylysine / Q000737:chemistry* / Q000302:isolation & purification*; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*; D059027:Recycling / Q000379:methods*; D012996:Solutions; D013500:Surface Tension; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D000178:Acrylamides; D008689:Methacrylates; D011108:Polymers; D012996:Solutions; D014867:Water; D020106:Acrylamide; D011107:Polylysine; C086861:poly-N-vinylcaprolactam; D002209:Caprolactam; C067295:N-isopropylacrylamide; C016284:butyl methacrylate
keywords: Aqueous two-phase systems; Low-field nuclear magnetic resonance; Phase-forming mechanism; Thermo-responsive copolymer; ε-polylysine partition