A Simple and Ultrasensitive Colorimetric Biosensor for Anatoxin-a Based on Aptamer and Gold Nanoparticles.

ABSTRACT: Here, we designed a simple, rapid, and ultrasensitive colorimetric aptasensor for detecting anatoxin-a (ATX-a). The sensor employs a DNA aptamer as the sensing element and gold nanoparticles (AuNPs) as probes. Adsorption of the aptamer onto the AuNP surface can protect AuNPs from aggregation in NaCl solution, thus maintaining their dispersion state. In the presence of ATX-a, the specific binding of the aptamer with ATX-a results in a conformational change in the aptamer, which facilitates AuNP aggregation and, consequently, a color change of AuNPs from red to blue in NaCl solution. This color variation is directly associated with ATX-a concentration and can be easily measured using a UV/Vis spectrophotometer. The absorbance variation is linearly proportional to ATX-a concentration across t

SUBMITTER: Nguyen DK 

PROVIDER: S-EPMC8703760 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature