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

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 0.5mL of serum. Significant correlation (r=0.998) was found over the range from 0.1 to 8ng/mL, with better performance in terms of accuracy, precision, and selectivity. Validation was made with human serum spiked at two levels, 0.5 and 2.0ng/mL,26 and natural contaminated serum. Average recoveries of OTA using different extraction methods ranged from 58.484.56 to 94.853.52%. Immunoaffinity cleanup showed a better recovery rate, with a lower detection limit validated at 0.1ng/mL. The cited method can be used as a rapid and noninvasive tool to assess human and animal exposure to OTA.