Highly Sensitive Colorimetric Detection of Ochratoxin A by a Label-Free Aptamer and Gold Nanoparticles

Toxins (Basel). 2015 Dec 10;7(12):5377-85. doi: 10.3390/toxins7124883.

Abstract

A label-free aptamer-based assay for the highly sensitive and specific detection of Ochratoxin A (OTA) was developed using a cationic polymer and gold nanoparticles (AuNPs). The OTA aptamer was used as a recognition element for the colorimetric detection of OTA based on the aggregation of AuNPs by the cationic polymer. By spectroscopic quantitative analysis, the colorimetric assay could detect OTA down to 0.009 ng/mL with high selectivity in the presence of other interfering toxins. This study offers a new alternative in visual detection methods that is rapid and sensitive for OTA detection.

Keywords: Ochratoxin A (OTA); aptamer; cationic polymer; colorimetric assay; gold nanoparticles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcoholic Beverages / analysis
  • Aptamers, Nucleotide / chemistry*
  • Colorimetry
  • Food Contamination / analysis
  • Gold / chemistry*
  • Metal Nanoparticles / chemistry*
  • Ochratoxins / analysis*
  • Ochratoxins / chemistry
  • Polyethylenes / chemistry
  • Quaternary Ammonium Compounds / chemistry
  • Sodium Chloride / chemistry

Substances

  • Aptamers, Nucleotide
  • Ochratoxins
  • Polyethylenes
  • Quaternary Ammonium Compounds
  • ochratoxin A
  • poly-N,N-dimethyl-N,N-diallylammonium chloride
  • Sodium Chloride
  • Gold