Advances in imaging-assisted sensing techniques for heavy metals in water: Trends, challenges, and opportunities

Abstract

Heavy metal pollution of water resources is of worldwide concern, stimulating the development of breakthroughs in detection and remedy technologies. In the digital age, imaging solutions have been applied to almost every sector of civil society, from health and manufacturing to diagnostics, defense, and personal security. The next generation of monitoring sensors and systems for water quality and pollutants is developing at a rapid pace. The present review discusses various aspects of imaging-assisted quantification of heavy metals in water, including transduction techniques (colorimetric and photoluminescence), sensor materials (organic linkers, metal nanoparticles, carbonaceous & semiconductor quantum dots, etc.), the roles of equipment and readout tools (color charts, image scanners, digital cameras, mobile phones, etc.), substrates (organic and inorganic), and sampling methods. To the best of our knowledge, no such efforts have been made previously to critically and comprehensively analyze various aspects on the new imaging-based technologies in the environmental sector.