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Uncertainty in aflatoxin B1 analysis using information from proficiency tests.

Alicia Maroto·Ricard Boqué·Jordi Riu·Itziar Ruisánchez·Marta Odena
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Abstract

We describe how to calculate uncertainty in the determination of aflatoxin B(1) in nuts and maize using an HPLC method with prederivatisation with trifluoroacetic acid and fluorescence detection. The uncertainty is easily calculated using the information obtained from the participation in several proficiency tests. All the sources of uncertainty are grouped in two terms: (1) matrix variability, intermediate precision and sample heterogeneity, and (2) method concordance. This methodology has the advantage that no extra work needs to be done because all the information to calculate uncertainty comes from proficiency tests. The uncertainty values were calculated using samples whose concentration ranged between 2 and 20 microg L(-1). The relative standard uncertainty computed for aflatoxin B(1) was 16.3%.

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Aflatoxin B1Chromatography, High Pressure LiquidFood AnalysisFood ContaminationNutsReproducibility of ResultsSample SizeUncertaintyZea maysJournal Article

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Alicia Maroto, Ricard Boqué, Jordi Riu, Itziar Ruisánchez, Marta Odena. 2005-06-28. Uncertainty in aflatoxin B1 analysis using information from proficiency tests.. https://doi.org/10.1007/s00216-005-3321-2

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