Molecularly imprinted polymers having amidine and imidazole functional groups as an enzyme-mimetic catalyst for ester hydrolysis

Abstract

A molecularly imprinted polymer (MIP) having both amidine and imidazole functional groups in the active site has been prepared using p-nitrophenyl phosphate as a transition state analogue (TSA). The imprinted polymer MIP with amidine and imidazole found to have the highest hydrolysis activity compared with other MIPs with either amidine or imidazole groups only. It is postulated a cooperative effect between amidine and imidazole in the hydrolysis of p-nitrophenyl methyl carbonate (NPMC) as a substrate when both groups were arranged in proximity by molecular imprinting. The rate enhancement of the hydrolysis by MIP was 60 folds over the uncatalyzed solution reaction and two folds compared with the control non-imprinted polymer CP1 having both functional groups. The enzyme-mimetic catalytic hydrolysis of p-nitrophenyl acetate by MIP was evaluated in buffer at pH 7.0 with K m of 1.06 mM and k cat of 0.137 h -1 .

Molecular imprinting science and technology: a survey of the literature for the years up to and including 2003

“…More recently the work has been extended to the preparation of imprinted polymer catalysts using polymerizable amidine and imidazole monomers as arginine and histidine mimics for hydrolysis reactions. 1439 This work involved the imprinting of a 4-nitrophenyl phosphate template species as a TSA for the hydrolysis of 4-nitrophenylmethyl carbonate. Cooperativity was observed in the imprinted catalysts, with higher rates of carbonate hydrolysis observable in polymers imprinted with both amidine and imidazole functionality compared to imprinted polymers containing only one of these groups in the templated sites.…”

Synthesis and characterization of molecularly imprinted polymer for controlled release of tramadol

“…The applicability of the MIPs has led to numerous reports such as sensors and biosensors [7,8], as stationary phases for affinity chromatography [9], for membrane separation [10], as adsorbent for solid phase extraction [11], enzyme like catalysts [12], enantioseparation [13,14], or in pharmaceutical applications [15].…”

Preparation of core–shell structural surface molecular imprinting microspheres and recognition of l-Asparagine based on [N1111]Asn ionic liquid as template

“…Molecular imprinting has been applied to sensors and biosensors [4,5], solid-phase extraction [6], affinity chromatography [7][8][9], enzyme-like catalysts [10], enantioseparation [11,12], drug delivery [13], etc. The molecular imprinting technology is widely used and mostly focuses on non-biomolecules in organic solvent.…”