Ultra-sensitive detection of l-tyrosine using molecularly imprinted electrochemical sensor towards diabetic foot ulcer detection

Abstract It has been found that the concentration of l -tyrosine is greatly elevated within infected ulcers and thus there is a pressing need for sensors that can aid the point of care monitoring of this potential biomarker. In this work, a templated over-oxidised polypyrrole film on indium tin oxide is exploited as a sensitive sensing system, for the detection of tyrosine. The sensor has been characterised using a variety of surface techniques (contact angle, FTIR, SEM) and the electrochemical properties explored using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The sensor was found to exhibit a substantial linear range (100 fM−1 mM) with limits of detection of 1.73 pM (CV) and 6.63 pM (EIS). The sensor demonstrated rapid response characteristics (less than 1 minute) and high stability (up to 3 months).