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PubMed · 15808006

Immunoaffinity column cleanup with liquid chromatography using post-column bromination for aflatoxins in medicinal herbs and plant extracts.

Xuehui Zhang·Huiling Liu·Jianmin Chen
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Abstract

A new and accurate method to quantitate aflatoxins in medicinal herbs is developed. This method consists of extraction of the sample with MeOH-H2O (70:30) followed by clean-up of the extracts with immunoaffinity columns and, finally, high-performance liquid chromatographic determination with fluorescence detection. Aflatoxins B1 and G1 are determined as their bromine derivatives, produced in an online post-column derivatization system. The overall average recoveries for three different medicinal herbs spiked at levels of 1.3 and 2.6 ng/g of total aflatoxins range from 93% to 97%. The detection limit is 0.15 ng/g for both G2 and B2 and 0.20 ng/g for both G1 and B1, based on a signal-to-noise ratio of 3:1 and a precision (within-laboratory relative standard deviation) ranging from 0.8% to 1.4%. The use of immunoaffinity columns provides excellent clean-up of these particular extracts, which are generally difficult to analyze. The method is applied successfully to 96 samples of natural drugs.

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Aflatoxin B1AflatoxinsBromineChromatography, AffinityChromatography, High Pressure LiquidImmunologic TechniquesPlant ExtractsPlants, MedicinalJournal ArticleResearch Support, Non-U.S. Gov't

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Xuehui Zhang, Huiling Liu, Jianmin Chen. 2005. Immunoaffinity column cleanup with liquid chromatography using post-column bromination for aflatoxins in medicinal herbs and plant extracts.. https://doi.org/10.1093/chromsci%2F43.1.47

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