Formalin Detection using Platinum Electrode-Based Electrochemical System

The present work concentrated on a rapid electrochemical detection system of formaldehyde content using a platinum-based noble metal electrode. Formalin, an aqueous solution of formaldehyde is globally used as food preservative. In this work, analysis of electrochemical behavior of the electrode has been studied using a three-electrode system against a silver–silver chloride reference electrode and a steel counter electrode. Voltammetry technique has been employed for the experimental study. The cyclic voltammetry (CV) responses obtained within a range of applied potential − 0.1 V to 1.6 V; depicted effective evidence about formalin existence. Differential pulse voltammetry (DPV) results have portrayed successful quantification of various formalin concentrations. Analysis of electrochemical responses provided a broad linear working range for the sensor from 100 µM to 1000 µM. A lowest limit of detection (LOD) was attained as 5 µM. Several concentrations 100 µM, 50 µM, 10 µM and 5 µM have also been evaluated by means of principal component analysis (PCA) with effective data clustering. The separability index (SI) was found as 25.68. Support vector machine (SVM), linear discriminant classifier, KNN and Ensemble have been employed, and a 100% classification accuracy of the electrode was found. Further, a prediction estimation of formalin contents by means of PLSR (partial least square regression) as well as PCR (principal component regression) algorithms were also evaluated with 97.84% and 97.66% prediction accuracies, respectively. This electrochemical system may be subjected for fast formalin detection in our daily life food consumption. © 2022, The Institution of Engineers (India).