Quenching Behavior of the Electrochemiluminescence of Ru(bpy)₃²⁺/TPrA System by Phenols on a Smartphone‐Based Sensor

Abstract

Phenolic compounds such as vanillic and p ‐coumaric acids are pollutants of major concern in the agro‐industrial processing, thereby their effective detection in the industrial environment is essential to reduce exposure. Herein, we present the quenching effect of these compounds on the electrochemiluminescence (ECL) of the Ru(bpy) 3 2+ /TPrA (TPrA=tri‐ n ‐propylamine) system at a disposable screen‐printed carbon electrode. Transient ECL profiles are obtained from multiple video frames following 1.2 V application by a smartphone‐based ECL sensor. A wide range of detection was achieved using the sensor with limit of detection of 0.26 μ m and 0.68 μ m for vanillic and p ‐coumaric acids, respectively. The estimated quenching constants determined that the quenching efficiency of vanillic acid is at least two‐fold that of p ‐coumaric acid under the current detection conditions. The present ECL quenching approach provided an effective method to detect phenolic compounds using a low‐cost, portable smartphone‐based ECL sensor.

Machine Learning Analysis for Phenolic Compound Monitoring Using a Mobile Phone-Based ECL Sensor

“…The data were split into five groups while an average of four groups (80%) were used to generate a calibration curve and the one group (20%) was employed to report the performance. We used ECL intensity for the calibration curve because all our previous work used only ECL intensity as a sole feature for data regression [ 14 , 15 , 17 ]. For Vanillic acid, the traditional nonlinear calibration curves using the peak intensity scored an MAE of 4.50 μM with a standard deviation of 1.1 μM in the concentration prediction.…”

“…The excited state of the luminophore [Ru(bpy) 3 ] 2+ *, which is generated from a series of redox reactions, can decay to the ground state [Ru(bpy) 3 ] 2+ without ECL emission in the presence of the oxidation products of the phenolic compounds, such as o - or p -benzoquinone. Details of the quenching mechanism have been described elsewhere [ 17 ]. The quantitative investigation of the ECL quenching mechanism to detect the concentration of involved species naturally leads to the use of partial differential equations that constitute complex mechanistic models.…”