Electrochemical Synthesis of Molecularly Imprinted Polymers for L-Tyrosine Detection

Abstract

L-Tyrosine (L-Tyr), a critical amino acid whose aberrant levels impact melanin and dopamine levels in human body while also increasing insulin resistance thereby increasing the risk of type 2 diabetes. The objective of this study was to detect the amount of L-Tyr in human fluids by tailored electrochemical synthesis of well adhered, homogenous and thin molecularly imprinted polymers (MIPs) by the electro-polymerization of pyrrole on glassy carbon electrode modified functionalized multi-walled carbon nanotubes. The key benefits of this procedure over previous imprinting techniques were the elimination of expensive materials like Au and tedious multi-step synthesis, for L-Tyr detection using a handheld potentiostat. The developed particles were characterized using Fourier Transform Infrared Spectroscopy, Scanning Electron Microscope, Chronoamperometry, and Cyclic Voltammetry. With strong reproducibility and stability, this optimized approach provides a rapid and effective method of preparing and sensing MIPs for the target analyte with a broad linear range of $1~\mu \text{M}$ to $2000~\mu \text{M}$ . The Limit of Detection and Limit of Quantification were $0.4~\mu \text{M}$ and $1.47~\mu \text{M}$ , respectively. The engineered sensor was validated for quantifying the concentrations of L-Tyr in human blood and serum samples, yielding satisfactory recovery and can be expanded in future to detect analytes simultaneous.