Although, Ag NPs have been used in less extension than Au NPs in the development of this kind of colorimetric assays, very interesting works have been published based on colour change from
yellow to brown corresponding to dispersed and aggregated AgNPs, respectively. In this section, these AgNP-based colorimetric assays will be discussed in three sub-sections: detection of organic
and inorganic analytes as well as detection based on the use of both,Au and Ag NPs