A colorimetric aptamer-based method for detection of cadmium using the enhanced peroxidase-like activity of Au-MoS2 nanocomposites

Zui Tao; Liting Wei; Shijia Wu; Nuo Duan; Xiang Li; Zhouping Wang

doi:10.1016/j.ab.2020.113844

A colorimetric aptamer-based method for detection of cadmium using the enhanced peroxidase-like activity of Au-MoS₂ nanocomposites

Anal Biochem. 2020 Nov 1:608:113844. doi: 10.1016/j.ab.2020.113844. Epub 2020 Aug 4.

Authors

Zui Tao¹, Liting Wei¹, Shijia Wu¹, Nuo Duan¹, Xiang Li¹, Zhouping Wang²

Affiliations

¹ State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, PR China.
² State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, PR China; Collaborative Innovation Center of Food Safety and Quality Control of Jiangsu Province, Jiangnan University, Wuxi, 214122, China. Electronic address: wangzp@jiangnan.edu.cn.

PMID: 32763304
DOI: 10.1016/j.ab.2020.113844

Abstract

In this work, a colorimetric aptamer-based method for detection of cadmium using gold nanoparticles modified MoS₂ nanocomposites as enzyme mimic is established. In short, biotinylated Cd²⁺ aptamers are immobilized by biotin-avidin binding on the bottoms of the microplate, the complementary strands of Cd²⁺ aptamers are connected to the Au-MoS₂ nanocomposites which have the function of enhanced peroxidase-like activity. The csDNA-Au-MoS₂ signal probe and target Cd²⁺ compete for binding Cd²⁺ aptamer, the color change can be observed by addition of chromogenic substrate, thereby realizing visual detection of Cd²⁺. The absorbance of the solution at 450 nm has a clear linear relationship with the Cd²⁺ concentration. The linear range is 1-500 ng/mL, and the limit of detection is 0.7 ng/mL. The assay was used to test white wine samples, the results are consistent with those of atomic absorption spectrometry; which prove that this method can be used for detection of Cd²⁺ in real samples.

Keywords: Aptamer; Cadmium ions; Enzyme mimics; Gold nanoparticles; MoS(2) nanosheets; Signal enhancement.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aptamers, Nucleotide / chemistry*
Cadmium / analysis*
Cadmium / chemistry*
Cations, Divalent / analysis*
Cations, Divalent / chemistry*
Chromogenic Compounds / chemistry
Colorimetry / methods*
DNA, Complementary / chemical synthesis
DNA, Complementary / chemistry
Disulfides / chemistry
Enzyme Assays / methods
Gold / chemistry
Microscopy, Electron, Transmission
Molybdenum / chemistry
Nanocomposites / chemistry*
Oxidation-Reduction
Peroxidases / chemistry
Spectrophotometry
Wine / analysis
X-Ray Diffraction

Substances

Aptamers, Nucleotide
Cations, Divalent
Chromogenic Compounds
DNA, Complementary
Disulfides
Cadmium
Gold
Molybdenum
Peroxidases
molybdenum disulfide