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Validation of a high-performance liquid chromatography analytical method for ochratoxin A quantification in cocoa beans.

S Amézqueta·E González-Peñas·M Murillo·A López de Cerain
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Abstract

A validated high-performance liquid chromatography (HPLC) method with fluorescence detection for the quantitative analysis of ochratoxin A (OTA) in cocoa beans is described. OTA was extracted with methanol-3% sodium hydrogen carbonate solution and then purified with immunoaffinity columns before its analysis by HPLC. The validation of the analytical method was based on the following criteria: selectivity, linearity, limit of detection and quantification, precision (within- and between-day variability) and recovery, robustness and uncertainty. Detection and quantification limits were 0.04 and 0.1 mug kg(-1), respectively. Recovery was 88.9% (relative standard deviation = 4.0%). This method was successfully applied to the measurement of 46 cocoa bean samples of different origins. A total of 63% of cocoa bean samples was contaminated with a level greater than the limit of detection. The means and medians obtained for cocoa bean were 1.71 and 1.12 mug kg(-1), respectively. Surveillance controls should be set up in both crops and factories involved in transformation processes to avoid this mycotoxin in final products.

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CacaoChromatography, High Pressure LiquidFood AnalysisFood ContaminationHumansMycotoxinsOchratoxinsReproducibility of ResultsJournal ArticleResearch Support, Non-U.S. Gov'tValidation Study

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S Amézqueta, E González-Peñas, M Murillo, A López de Cerain. 2004. Validation of a high-performance liquid chromatography analytical method for ochratoxin A quantification in cocoa beans.. https://doi.org/10.1080/02652030400019422

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