Determination of Ochratoxin A in Human Blood Serum by High-Performance Liquid Chromatography : Method Validation and Comparison of Extraction Procedures

Abstract A high-performance liquid chromatography method for determination of ochratoxin A (OTA) in human blood serum has been validated. A liquid-liquid partition, solid-phase extraction and immunoaffinity cleanup was applied for OTA extraction from 0.5 mL of serum. Significant correlation (r = 0.998) was found over the range from 0.1 to 8 ng/mL, with better performance in terms of accuracy, precision, and selectivity. Validation was made with human serum spiked at two levels, 0.5 and 2.0 ng/mL,26 and natural contaminated serum. Average recoveries of OTA using different extraction methods ranged from 58.48 ± 4.56 to 94.85 ± 3.52%. Immunoaffinity cleanup showed a better recovery rate, with a lower detection limit validated at 0.1 ng/mL. The cited method can be used as a rapid and noninvasive tool to assess human and animal exposure to OTA.