Ultrasensitive Catechol Detection via Core-Shell Nanofibers: Effect of Type of Conducting Polymer and MWCNT Reinforcement

Abstract

The detection of phenols is one of the main research directions due to impact of phenols on human life. Herein, novel biosensing matrices based on pristine and composite (including MWCNTs) electrospun nanofibers coated with conducting polymers (poly(3,4-ethylenedioxythiphene (PEDOT) or polypyrrole (PPy)) were employed for immobilization of Tyrosinase enzyme and further evaluated for phenol detection. The current study is meant to provide a comparison between the two conducting polymers in terms of electron transfer and biocompatibility with the chosen enzyme, as resulted from analytical characterization of the biosensor and analysis of Michaelis-Menten behaviour. The developed biosensors (Pt/PAN(-MWCNTs)/PEDOT NFs/PPO and Pt/PAN(-MWCNTs)/PPy NFs/PPO) displayed high sensitivity values of 6846.83 and 10364 μA mM−1.cm−2 within linear ranges of 5.0 − 1.0 × 10−5 and 5.0 − 1.0 × 10−7 M, with limit of detection values in the nanomolar range (1.14 and 4.04 × 10−7 M) depending on the polymer employed (PEDOT and PPy, respectively). Given the nanostructured conducting matrix based on the synergistic effect between MWCNTs and CPs and the principle of detection employed, the analytical parameters of the current study are competent in catechol detection. In addition, the platform screened possible interferences allowing accurate detection of trace amounts of phenolics in spiked water samples.