title: Block copolymer modified surfaces for conjugation of biomacromolecules with control of quantity and activity.
abstract: Polymer brush layers based on block copolymers of poly(oligo(ethylene glycol) methacrylate) (POEGMA) and poly(glycidyl methacrylate) (PGMA) were formed on silicon wafers by activators generated by electron transfer atom transfer radical polymerization (AGET ATRP). Different types of biomolecule can be conjugated to these brush layers by reaction of PGMA epoxide groups with amino groups in the biomolecule, while POEGMA, which resists nonspecific protein adsorption, provides an antifouling environment. Surfaces were characterized by water contact angle, ellipsometry, and Fourier transform infrared spectroscopy (FTIR) to confirm the modification reactions. Phase segregation of the copolymer blocks in the layers was observed by AFM. The effect of surface properties on protein conjugation was investigated using radiolabeling methods. It was shown that surfaces with POEGMA layers were protein resistant, while the quantity of protein conjugated to the diblock copolymer modified surfaces increased with increasing PGMA layer thickness. The activity of lysozyme conjugated on the surface could also be controlled by varying the thickness of the copolymer layer. When biotin was conjugated to the block copolymer grafts, the surface remained resistant to nonspecific protein adsorption but showed specific binding of avidin. These properties, that is, well-controlled quantity and activity of conjugated biomolecules and specificity of interaction with target biomolecules may be exploited for the improvement of signal-to-noise ratio in sensor applications. More generally, such surfaces may be useful as biological recognition elements of high specificity for functional biomaterials.
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren'ai Road, Suzhou, 215123, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Shi
authors.forename: Yajun
authors.initials: Y
authors.lastname: Xu
authors.forename: Bo
authors.initials: B
authors.lastname: Song
authors.forename: Hong
authors.initials: H
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D000890:Anti-Infective Agents / Q000737:chemistry*; D001360:Avidin / Q000737:chemistry; D001710:Biotin / Q000737:chemistry; D004579:Electron Transport; D005340:Fibrinogen / Q000737:chemistry*; D055767:Immobilized Proteins / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D009113:Muramidase / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D000890:Anti-Infective Agents; D055767:Immobilized Proteins; D008689:Methacrylates; D011109:Polymethacrylic Acids; C524499:polyethylene glycol methacrylate; D014867:Water; D001360:Avidin; C042535:polyglycidyl methacrylate; D011092:Polyethylene Glycols; D001710:Biotin; D005340:Fibrinogen; D009113:Muramidase; D012825:Silicon