Electrochemical Sensor Based on Molecularly Imprinted Polyaniline for Enantioselective Detection of Tyrosine Enantiomers

Abstract

A novel electrochemical sensor based on molecularly imprinted polyaniline (MIP) was developed for the selective recognition and quantitative determination of tyrosine enantiomers, with a particular focus on D-tyrosine (D-Tyr) in the presence of L-tyrosine (L-Tyr). The sensor was fabricated by electropolymerization of aniline in the presence of D-Tyr as a template on the surface of a glassy carbon electrode (GCE). Following template removal, specific recognition cavities complementary to the shape and functionality of D-Tyr were generated. The electrochemical behavior of the modified electrode was investigated using cyclic voltammetry (CV) and square wave voltammetry (SWV). The MIP/GCE exhibited excellent enantioselectivity toward D-Tyr, with minimal response to L-Tyr, demonstrating the successful imprinting and selective rebinding ability of the sensor. The developed sensor showed a linear response in the concentration range of 25–800 μM for D-Tyr, with a detection limit of 7.9 nM. The proposed method offers several advantages, including high sensitivity, low cost, operational simplicity, and the ability to discriminate between structurally similar enantiomers. This sensor holds promise for applications in pharmaceutical analysis, biomedical diagnostics, and enantiomeric purity assessment.