Highly Sensitive and Selective Colorimetric Detection of Methylmercury Based on DNA Functionalized Gold Nanoparticles.

ABSTRACT: A new colorimetric detection of methylmercury (CH?Hg?) was developed, which was based on the surface deposition of Hg enhancing the catalytic activity of gold nanoparticles (AuNPs). The AuNPs were functionalized with a specific DNA strand (HT7) recognizing CH?Hg?, which was used to capture and separate CH?Hg? by centrifugation. It was found that the CH?Hg? reduction resulted in the deposition of Hg onto the surface of AuNPs. As a result, the catalytic activity of the AuNPs toward the chromogenic reaction of 3,3,5,5-tetramethylbenzidine (TMB)-H?O? was remarkably enhanced. Under optimal conditions, a limit of detection of 5.0 nM was obtained for CH?Hg? with a linear range of 10?200 nM. We demonstrated that the colorimetric method was fairly simple with a low cost and can be conveniently applied to CH?Hg? detection in environmental samples.

SUBMITTER: Xie ZJ 

PROVIDER: S-EPMC6111283 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature