title: Fabrication of a surface imprinted hydrogel shell over silica microspheres using bovine serum albumin as a model protein template.
abstract: Surface imprinting is an effective approach to improve the template transfer efficiency in applications of molecularly imprinted polymers as biosensors and separation materials. In this paper, we tried to fabricate a surface imprinted hydrogel over silica microspheres for selective recognition of bovine serum albumin by covalent immobilization of a water-soluble UV sensitive initiator onto the surface of silica beads. The polymerization was initiated by UV radiation with N-[3-(dimethylamino)propyl]methacrylamide and N-isopropylacrylamide as the functional monomer and assistant monomer, respectively, and a thin coat of stimuli-responsive hydrogel yielded over the silica gels. The surface imprinted hydrogels exhibited specific affinity toward the template protein with an association constant (K(a)) of 2.2 x 10(5)L mol(-1) and a maximum binding capacity (Q(max)) of 27.3 mgg(-1) in Tris-HCl buffer (pH 7.0). The rebinding and desorption kinetics of the surface imprinted hydrogels were determined and proven to be extremely fast (about 1 min compared to 3h for the previously prepared bulk imprinted hydrogel). Besides, the hydrogel-silica core-shell particles inherit both the stimuli-responsive property of the hydrogel and the good mechanical strength of the silica beads based on the on-line evaluation with high-performance liquid chromatography. The above comprehensive merits of the obtained surface imprinted hydrogel suggest the presented approach an attractive and broadly applicable way of developing biosensors and high-performance protein separation materials.
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry & Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Zhendong
authors.initials: Z
authors.lastname: Hua
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhou
authors.forename: Meiping
authors.initials: M
authors.lastname: Zhao
mesh_terms: D000327:Adsorption; D000818:Animals; D001391:Azo Compounds / Q000737:chemistry; D001665:Binding Sites; D015374:Biosensing Techniques; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D020100:Hydrogels; D066298:In Vitro Techniques; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D054802:Molecular Imprinting / Q000379:methods*; D011506:Proteins / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012822:Silicon Dioxide; D013499:Surface Properties; D014466:Ultraviolet Rays; D014631:Valerates / Q000737:chemistry
chemical_list: D001391:Azo Compounds; D020100:Hydrogels; D011506:Proteins; D014631:Valerates; C091250:4,4'-azobis(4-cyanovaleric acid); D012710:Serum Albumin, Bovine; D012822:Silicon Dioxide