Development of a biotin-streptavidin-amplified nanobody-based ELISA for ochratoxin A in cereal

Ecotoxicol Environ Saf. 2019 Apr 30:171:382-388. doi: 10.1016/j.ecoenv.2018.12.103. Epub 2019 Jan 4.

Abstract

A biotin-streptavidin-amplified enzyme-linked immunosorbent assay using a biotinylated nanobody (BA-Nb ELISA) was developed to detect ochratoxin A (OTA) in cereal. The limit of detection (LOD) of the BA-Nb ELISA, which equals to 10% maximal inhibitory concentration, was 0.011 ng/mL for OTA in buffer, and the sensitivity was approximately improved by one order of magnitude compared with the traditional Nb ELISA (LOD = 0.112 ng/mL). Under optimal conditions, the developed assay could be accomplished in 40 min with maximal inhibitory concentration of 0.138 ng/mL and the linear detection range of 0.034-0.460 ng/mL. The average recovery rate of the BA-Nb ELISA ranged from 92.8% to 114%, and the relative standard deviation was in the range of 2.04-9.85%. The developed BA-Nb ELISA was validated by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the results indicated the reliability of BA-Nb ELISA for the detection of OTA in cereal.

Keywords: Biotin-streptavidin amplification; Cereal; Immunoassay; Nanobody; Ochratoxin A.

MeSH terms

  • Biotin / chemistry*
  • Edible Grain / chemistry*
  • Enzyme-Linked Immunosorbent Assay
  • Limit of Detection
  • Ochratoxins / analysis*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Streptavidin / chemistry*
  • Tandem Mass Spectrometry

Substances

  • Ochratoxins
  • ochratoxin A
  • Biotin
  • Streptavidin