Sensitive and selective colorimetric detection of Hg(2+) by a Hg(2+) induced dual signal amplification strategy based on cascade-type catalytic reactions.

A simple and fast colorimetric method is developed for the sensitive and selective detection of Hg(2+) based on a dual signal amplification strategy: in situ Hg(2+) induced catalytic synthesis of oxidase-like AuHg nanoparticles and subsequent catalytic oxidation of TMB by AuHg nanoparticles.