Selective enrichment of ochratoxin A using human serum albumin bound magnetic beads as the concentrating probes for capillary electrophoresis/electrospray ionization-mass spectrometric analysis.
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.
Hong
Chen-Yu
CY
Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan.
Chen
Yu-Chie
YC
D000418:Albumins / Q000737:chemistry; D002846:Chromatography, Affinity / Q000379:methods; D020099:Coated Materials, Biocompatible; D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination; D006801:Humans; D008280:Magnetics; D009793:Ochratoxins / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation* / Q000379:methods; D013056:Spectrophotometry, Ultraviolet; D018511:Systems Integration; D014920:Wine / Q000032:analysis*
D000418:Albumins; D020099:Coated Materials, Biocompatible; D009793:Ochratoxins