On-site, rapid and visual method for nanomolar Hg²⁺ detection based on the thymine-Hg²⁺-thymine triggered "double" aggregation of Au nanoparticles enhancing the Tyndall effect.

ABSTRACT: This work describes a new nanosensor for the simple, rapid, portable, colorimetric analysis of mercury(ii) (Hg²⁺) ions by combining the sensitive Tyndall effect (TE) of colloidal Au nanoparticles (AuNPs) with specific thymine-Hg²⁺-thymine (T-Hg²⁺-T) coordination chemistry for the first time. For the TE-inspired assay (TEA), in the presence of Hg²⁺ in a sample, the analyte can selectively mediate the hybridization of three types of flexible single-stranded DNAs (ssDNAs) to form stable rigid double-stranded DNAs (dsDNAs) via the T-Hg²⁺-T ligand interaction. Subsequent self-assembly of the dsDNAs with terminal thiol groups on the AuNPs' surfaces led to their "double" aggregation in addition to the lack of sufficient ssDNAs as the s

SUBMITTER: Chen X 

PROVIDER: S-EPMC9043572 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature