Quantification of the silver content of a silver-plated nylon electrode according to the nature of the laundering detergent

Abstract

In this study, the loss of the silver content was determined accurately when silver plated nylon electrodes dedicated to a measurement of human physiological parameters are washed with detergents containing bleaching agents. Thermogravimetric analysis and morphological observations based on SEM images have been conducted to determine the quantity of remaining silver on the electrodes. This loss of the conductive silver content is critical for the electrodes as it reduces their electrical conductivity and therefore their capacity to be used to measure either low voltages from the skin generated by ECG (electrocardiograph), EMG (electromyograph) or even EEG (electroencephalograph) or to determine the bioimpedance of human body or specific organs. The reduced surface conductivity leads also to a very complex contact impedance between the electrodes and the skin and therefore to their high sensitivity to any movement. This also results in noisy signals that are not useful to monitoring of physiological parameters and the concept of predictive medicine.