A Molecularly Imprinted Copolymer Designed for Enantioselective Recognition of Glutamic Acid

Abstract

A newly designed molecularly imprinted polymer (MIP) material was developed and successfully used as recognition element to fabricate a capacitive sensor for enantioselective recognition of glutamic acid (Glu). The MIP with a well‐defined structure was synthesized on a gold electrode in one step by electrochemical copolymerization of o‐phenylenediamine (o‐PD) and dopamine (DA) in the presence of template molecule Glu. The resulting MIP material was characterized with a potentiostatic frequency scan method, cyclic voltammetry, capacitance measurements, atomic force microscopy, and X‐ray photoelectron spectroscopy. The structure and recognition behaviour of the copolymer film to template molecule depended on its composition. The optimal composition was at the o‐PD to DA molar ratio of 3:2. With a potentiostatic time scan method the copolymer displayed high enantioselectivity and sensitivity to the stereoselective rebinding of L‐ or D‐Glu to their corresponding artificial receptor due to the exact definition of the imprint cavity. The capacitance response of the sensor for L‐Glu or D‐Glu was proportional to their concentration in the range of 16.7 to 250 μM. The enantiometric selectivity coefficients for L‐Glu and D‐Glu imprinted films against their respective enantiomers are 24 and 15, respectively. The resulting MIP capacitive sensors showed good reproducibility, stability and repeatability. This strategy opened a convenient way for preparation of enantioselective MIPs and recognition of enantiotropic molecules.

Myoblast Cell Interaction with Polydopamine Coated Liposomes

“…rendering hydrophobic surface cell adhesive [17] to building blocks in biosensing platforms e.g. as matrix polymer for molecular imprinting [18], and for life cell encapsulation [19]. PDA capsules have been considered using particles [20][21][22][23] or oil emulsion droplets [24] as templates.…”

Carbon Nanotubes – Imprinted Polymers: Hybrid Materials for Analytical Applications

“…et al, 2003), which were used to detect many different analytes (Augisto et al, 2010) such as barbituric acid (Mirsky et al, 1999), amino acid derivatives (Panasyuk et al, 1999), morphine , atrazine (Kim Y. et al, 2007), benzyltriphenylphosphonium chloride , thiophenol (Kröger et al, 1999), glutamic acid (Ouyang et al, 2007), folic acid (Prasad et al, 2010a;Prasad et al, 2010c), tolazoline (Zhang Z. et al, 2010a), tryptophan (Prasad et al, 2010d;Kong Y. et al, 2010), clindamycin , 2,4-dichlorophenoxy acetic acid (Xie et al, 2010), histamine (Bongaers et al, 2010) Despite the application of MIPs as sensor matrices or separation materials, they suffer from basic limitations associated with the limited concentration of imprinted sites, and the bulk volume of the polymer matrices that requires long diffusion paths of the imprinted host molecules. These limitations lead to inefficient sensing or separation processes .…”

New Materials in Electochemical Sensors for Pesticides Monitoring

“…Recently electrosynthesized polymers such as poly(dopamine) (PDA) and poly(ophenylendiamine) (Po-PD) have been prepared to form a novel well-defined structure MIP at an electrode. The designed copolymer film could be used for the recognition of the enantiomer, as a capacitive sensor (Ouyang et al, 2007) On the other hand some authors have focused their studies on the "gate effect" which is a phenomenon where solute permeability of the molecularly imprinted polymer membrane changes with specific binding with the template . The "gate effect" is probably caused by a morphological change in the polymer matrix due to specific binding with the template, similar to the "induced fit" of the natural receptors.…”