Development of a Sensitive Enzyme-Linked Immunosorbent Assay and Rapid Gold Nanoparticle Immunochromatographic Strip for Detecting Citrinin in Monascus Fermented Food

Toxins (Basel). 2018 Sep 2;10(9):354. doi: 10.3390/toxins10090354.

Abstract

Antibodies against citrinin (CTN) were generated from rabbits, which were injected with CTN-keyhole limpet hemocyanin (KLH). This work involved the development of a sensitive competitive direct enzyme-linked immunosorbent assay (cdELISA) and a rapid gold nanoparticle immunochromatographic strip (immunostrip) method for analyzing CTN in Monascus-fermented food. CTN at a concentration of 5.0 ng/mL caused 50% inhibition (IC50) of CTN-horseradish peroxidase (CTN-HRP) binding to the antibodies in the cdELISA. The capable on-site detection of CTN was accomplished by a rapid antibody-gold nanoparticle immunostrip with a detection limit of 20 ng/mL and that was completed within 15 min. A close inspection of 19 Monascus-fermented foods by cdELISA confirmed that 14 were contaminated with citrinin at levels from 28.6⁻9454 ng/g. Further analysis with the immunostrip is consistent with those results obtained using cdELISA. Both means are sensitive enough for the rapid examination of CTN in Monascus-fermented food products.

Keywords: Citrinin; ELISA; Monascus fermented food; gold nanoparticle immunochromatographic strip.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies / immunology
  • Chromatography, Affinity
  • Citrinin / analysis*
  • Citrinin / immunology
  • Enzyme-Linked Immunosorbent Assay
  • Fermented Foods / analysis*
  • Food Contamination / analysis*
  • Gold
  • Hemocyanins / immunology
  • Horseradish Peroxidase / immunology
  • Metal Nanoparticles
  • Monascus / metabolism*
  • Ovalbumin / immunology

Substances

  • Antibodies
  • Citrinin
  • Gold
  • Ovalbumin
  • Hemocyanins
  • Horseradish Peroxidase
  • keyhole-limpet hemocyanin