Silver Inkjet-Printed Electrode on Paper for Electrochemical Sensing of Paraquat

The use of fully printed electrochemical devices has gained more attention for the monitoring of clinical, food, and environmental analytes due to their low cost, great reproducibility, and versatility characteristics, serving as an important technology for commercial application. Therefore, a paper-based inkjet-printed electrochemical system is proposed as a cost-effective analytical detection tool for paraquat. Chromatographic paper was used as the printing substrate due its sustainable and disposable characteristics, and an inkjet-printing system deposited the conductive silver ink with no further modification on the paper surface, providing a three-electrode system. The printed electrodes were characterized with scanning electron microscopy, cyclic voltammetry, and chronopotentiometry. The proposed sensor exhibited a large surface area, providing a powerful tool for paraquat detection due to its higher analytical signal. For the detection of paraquat, square-wave voltammetry was used, and the results showed a linear response range of 3.0-100 mu M and a detection limit of 0.80 mu M, along with the high repeatability and disposability of the sensor. The prepared sensors were also sufficiently selective against interference, and high accuracy (recovery range = 96.7-113%) was obtained when applied to samples (water, human serum, and orange juice), showing the promising applicability of fully printed electrodes for electrochemical monitoring.

Automated summary

The use of fully printed electrochemical devices for monitoring paraquat has been proposed as a cost-effective analytical detection tool, utilizing chromatographic paper as the printing substrate and conductive silver ink to construct a three-electrode system. The proposed sensor provides a large surface area and a high analytical signal, showing promising results in terms of selectivity, accuracy, and repeatability when applied to samples such as water, human serum, and orange juice.