Protein crystallization and biosensor applications of hydrogel-based molecularly imprinted polymers

Biomacromolecules. 2012 Dec 10;13(12):3959-65. doi: 10.1021/bm301189f. Epub 2012 Nov 9.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acrylamides / chemistry
  • Acrylamides / metabolism
  • Animals
  • Biosensing Techniques / instrumentation*
  • Biosensing Techniques / methods*
  • Cattle
  • Crystallization / methods
  • Hemoglobins / metabolism
  • Hydrogels / chemistry*
  • Molecular Imprinting*
  • Polymers / chemistry*
  • Protein Conformation
  • Quartz Crystal Microbalance Techniques / methods
  • Trypsin / metabolism

Substances

  • Acrylamides
  • Hemoglobins
  • Hydrogels
  • Polymers
  • N-isopropylacrylamide
  • Trypsin
  • N-methylolacrylamide