Optical and electrochemical techniques for Point-of-Care water quality monitoring: A review

Abstract

Water quality monitoring has become crucial due to the increasing exposure of water bodies to pollutants from the growing global population and industrialization. Detection strategies such as electrochemical and optical analysis techniques have gained popularity in environmental monitoring owing to their sensitivity, selectivity, rapidity, low cost, and easy operation that are not obtainable in the conventional methods. However, most sensors derived from these techniques are confined to laboratory significance and need experts for signals and results analysis. In recent times, many researchers have proposed the exploitation of the robustness of these optical and electrochemical techniques for point-of-care applications in water quality monitoring. In this review, different species of water contaminants, such as biological, physical, and chemical components, were quantified and successfully detected using POCs based on these techniques. The POCs sensors demonstrated high sensitivity, reliability, and relevance at the point of need. However, the designs and implementation of these portable POC systems to support high sensitivity, selectivity, low cost, less analysis time, and robustness when deployed in complex matrices remain a challenge. Comprehending and overcoming these setbacks and limitations demand more investigations and research resources, which could delay, at the least, the development, implementation, and commercialization of POCs, even when the need is very pressing and application and merits well lauded.