Colorimetric Sensing Applications of Metal and Metal Oxide Nanoparticles

Colorimetric sensing is a highly sensitive, quick and low-cost technique for the detection of various analytes, including metal, anions and organic contaminants. It is a hotspot for study since it is more efficient than its conventional equivalents. This chapter discusses the colorimetric sensing applications of several metal nanoparticles: gold, copper, iron and silver; metal oxide nanoparticles; zinc and copper oxides; and graphene, polymer and DNA. These nanoparticles are of particular interest due to their unique physical and chemical properties attributed to a reduction in surface-to-volume ratio. Here, we cover applications of colorimetric sensing in water pollution, food safety screening, food preservation, microbial contamination, heavy metal detection and detection of chemical weapons and explosives. We also cover cost-efficient methods of colorimetric detection properties of sensors such as localized surface plasmon resonance (LSPR), selectivity and sensitivity.