title: Synthesis of poly(N-isopropylacrylamide) particles for metal affinity binding of peptides.
abstract: Temperature-sensitive poly(N-isopropylacrylamide) (PNIPAM) microgel particles with metal affinity ligands were prepared for selective binding of peptides containing the His6-tag (six consecutive histidine residues). The PNIPAM particles were copolymerized with the functional ligand vinylbenzyl iminodiacetic acid (VBIDA) through a two-stage dispersion polymerization using poly(N-vinyl pyrrolidone) (PVP) as a steric stabilizer. The resulting particles were monodisperse in size and colloidally stable over a wide range of temperature and ionic strength due to chemically grafted PVP chains. The particle size was also found to be sensitive to ionic strength and pH of the aqueous environment, likely due to the electrostatic repulsion between ionized VBIDA groups. Divalent nickel ions were chelated to the VBIDA groups, allowing selective metal affinity attachment of a His6-Cys peptide. The peptide was released upon the addition of the competitive ligand imidazole, demonstrating that the peptide attachment to the particles is reversible and selective.
authors.affiliation: Department of Chemical Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627, United States.
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Tsai
authors.affiliation: Department of Chemical Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627, United States.
authors.forename: Alexander
authors.initials: A
authors.lastname: Lee
authors.affiliation: Department of Chemical Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Peng
authors.affiliation: Department of Chemical Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627, United States. Electronic address: myates@che.rochester.edu.
authors.forename: Matthew Z
authors.initials: MZ
authors.lastname: Yates
mesh_terms: D000180:Acrylic Resins / Q000138:chemical synthesis* / Q000737:chemistry; D002846:Chromatography, Affinity / Q000379:methods*; D006639:Histidine / Q000378:metabolism; D007098:Imino Acids / Q000737:chemistry; D007477:Ions; D007700:Kinetics; D008670:Metals / Q000378:metabolism*; D009532:Nickel / Q000302:isolation & purification; D009842:Oligopeptides / Q000378:metabolism; D010316:Particle Size; D010455:Peptides / Q000378:metabolism*; D058105:Polymerization; D011205:Povidone; D011485:Protein Binding; D013343:Styrenes / Q000737:chemistry; D013696:Temperature
chemical_list: D000180:Acrylic Resins; C471213:His-His-His-His-His-His; D007098:Imino Acids; D007477:Ions; D008670:Metals; C094450:N-(4-vinyl)benzyliminodiacetic acid; D009842:Oligopeptides; D010455:Peptides; D013343:Styrenes; C052970:poly-N-isopropylacrylamide; D006639:Histidine; D009532:Nickel; D011205:Povidone
keywords: Affinity binding; Colloidal stability; Microgel; Peptide carrier; Poly(N-isopropylacrylamide)