Selective enrichment of ochratoxin A using human serum albumin bound magnetic beads as the concentrating probes for capillary electrophoresis/electrospray ionization-mass spectrometric analysis

J Chromatogr A. 2007 Aug 3;1159(1-2):250-5. doi: 10.1016/j.chroma.2007.05.026. Epub 2007 May 16.

Abstract

Ochratoxin A (OTA) is a toxicant commonly present in many food products. Conventionally, immuno-affinity analysis is applied to rapidly screen the presence of OTA in food. However, antibodies are expensive. In this study, we present a new approach for selectively enriching OTA from aqueous samples using human serum albumin (HSA) bound magnetic beads as the affinity probes, followed by the analysis of CE/ESI-MS. In addition to demonstrating the feasibility of using the affinity probes to concentrate OTA, we also propose a rapid concentration and elution method for extraction, that is, OTA are extracted from aqueous samples by pipetting the samples in and out of a sample vial for 1 min followed by elution with pipetting for another minute. On the basis of the magnetic property, the affinity magnetic probe-target species could be rapidly isolated from the solution during the process of extraction and elution by magnetic separation. CE/ESI-MS, coupled by the electrodeless/sheathless interface, is used for the analysis of the samples. As this method features speed and cost-effectiveness, it is suitable for the purpose of rapid screening. In fact, the lowest detection limit for OTA is approximately 4 x 10(-3) mg/L.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Albumins / chemistry
  • Chromatography, Affinity / methods
  • Coated Materials, Biocompatible
  • Electrophoresis, Capillary / instrumentation*
  • Electrophoresis, Capillary / methods
  • Food Analysis / methods*
  • Food Contamination*
  • Humans
  • Magnetics
  • Ochratoxins / analysis*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Spectrometry, Mass, Electrospray Ionization / instrumentation*
  • Spectrometry, Mass, Electrospray Ionization / methods
  • Spectrophotometry, Ultraviolet
  • Systems Integration
  • Wine / analysis*

Substances

  • Albumins
  • Coated Materials, Biocompatible
  • Ochratoxins