title: New polymers forming aqueous two-phase polymer systems.
abstract: A new type of polymer, starch-modified by acrylamide, has been developed for application in aqueous two-phase systems (ATPS) for protein separation. Partial hydrolysis and acrylamide modification of starch to different degrees make it suitable for forming ATPS with poly(ethylene glycol) in a moderate concentration range. The potential of the polymer to form ATPS with the thermoprecipitating copolymer of 1-vinylimidazole with N-vinylcaprolactam (poly-VI/VCL) has been evaluated. The thermoprecipitation properties of poly-VI/VCL and Cu(II)-loaded poly-VI/VCL have been studied for application in metal affinity partitioning. The formation of ATPS with Cu(II)-loaded thermoprecipitating copolymer was critically achieved for poly-VI/VCL (10/90) copolymer in under-loaded metal concentrations. With the Cu(II)-loaded copolymer, poly-VI/VCL in the top phase and modified starch in the bottom phase, the ATPS formed was used for the purification of alpha-amylase inhibitor from wheat meal. The protein partitioned in the top phase and phase-separated polymer-protein complex could be precipitated by salt. The protein inhibitor was recovered with a yield of 75%.
authors.affiliation: Department of Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, Lund, S-221 00, Sweden.
authors.forename: N
authors.initials: N
authors.lastname: Pietruszka
authors.forename: I Y
authors.initials: IY
authors.lastname: Galaev
authors.forename: A
authors.initials: A
authors.lastname: Kumar
authors.forename: Z K
authors.initials: ZK
authors.lastname: Brzozowski
authors.forename: B
authors.initials: B
authors.lastname: Mattiasson
mesh_terms: D020106:Acrylamide / Q000737:chemistry; D002209:Caprolactam / Q000031:analogs & derivatives* / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D007093:Imidazoles / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011145:Polyvinyls; D014867:Water / Q000737:chemistry
chemical_list: C411948:1-vinylimidazole-N-vinylcaprolactam copolymer; D007093:Imidazoles; D011108:Polymers; D011145:Polyvinyls; D014867:Water; D020106:Acrylamide; D002209:Caprolactam; D003300:Copper; C425704:N-vinylimidazole