title: Protein crystallization and biosensor applications of hydrogel-based molecularly imprinted polymers.
abstract: We have characterized the imprinting capability of a family of acrylamide polymer-based molecularly imprinted polymers (MIPs) for bovine hemoglobin (BHb) and trypsin (Tryp) using spectrophotometric and quartz crystal microbalance (QCM) sensor techniques. Bulk gel characterization on acrylamide (AA), N-hydroxymethylacrylamide (NHMA), and N-isopropylacrylamide (NiPAM) gave varied selectivities when compared with nonimprinted polymers. We have also harnessed the ability of the MIPs to facilitate protein crystallization as a means of evaluating their selectivity for cognate and noncognate proteins. Crystallization trials indicated improved crystal formation in the order NiPAM<AA<NHMA. QCM studies of thin film MIPs confirm this trend with N-hydroxymethyl acrylamide MIPs exhibiting best discrimination between MIP and NIP and also cognate/noncognate protein loading. Equivalent results for acrylamide MIPs suggested that the cavities were equally selective for both proteins, while N-isopropylacrylamide MIPs were not selective for either cognate BHb or noncognate BSA. All BHb MIP-QCM sensors based on AA, NHMA, or NiPAM were essentially nonresponsive to smaller, noncognate proteins. Protein crystallization studies validated the hydrophilic efficacy of MIPS indicated in the QCM studies.
authors.affiliation: Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, GU2 7XH, United Kingdom. s.reddy@surrey.ac.uk
authors.forename: Subrayal M
authors.initials: SM
authors.lastname: Reddy
authors.forename: Quan T
authors.initials: QT
authors.lastname: Phan
authors.forename: Hazim
authors.initials: H
authors.lastname: El-Sharif
authors.forename: Lata
authors.initials: L
authors.lastname: Govada
authors.forename: Derek
authors.initials: D
authors.lastname: Stevenson
authors.forename: Naomi E
authors.initials: NE
authors.lastname: Chayen
mesh_terms: D000178:Acrylamides / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D002417:Cattle; D003460:Crystallization / Q000379:methods; D006454:Hemoglobins / Q000378:metabolism; D020100:Hydrogels / Q000737:chemistry*; D054802:Molecular Imprinting; D011108:Polymers / Q000737:chemistry*; D011487:Protein Conformation; D058525:Quartz Crystal Microbalance Techniques / Q000379:methods; D014357:Trypsin / Q000378:metabolism
chemical_list: D000178:Acrylamides; D006454:Hemoglobins; D020100:Hydrogels; D011108:Polymers; C067295:N-isopropylacrylamide; D014357:Trypsin; C066443:N-methylolacrylamide