Aflatoxin solid-phase extraction

This sample preparation involved, firstly, an extraction and the elimination of the solid matrix by filtration and, secondly, a concentration procedure employing a solid phase extraction cartridge. The compounds of interest were separated solely by dispersive interactions with the reversed phase. In the example given, the corn meal was spiked with the aflatoxins. 

Basically the cleanup step consists of one of the two approaches already described in the aflatoxin section (a) the use of solid-phase extraction (SPE) columns, or (b) the use of immunoaffinity (IA) columns. 

The slope is almost prefect but there is a small (1%) proportional-systematic error. The y axis intercept has a constant-systematic bias one finds an aflatoxin content which is too low by 2.9 mg. The solid phase extraction must be improved. 

Roch, O. G., Blunden, G., Coker, R. D., and Nawaz, S. 1992. The development and validation of a solid phase extraction/HPLC method for the determination of aflatoxins in groundnut meal, Chromatographia, 33 208-212. 

The analysis of food contaminants, in particular any toxic or biologically active residue, is important for public health or quality control reasons.19 Examples are mycotoxins (aflatoxins) and pesticide and drug residues. Sample preparation is typically elaborate and might involve deproteinization, solvent extraction, and clean-up via solid-phase extraction (SPE).The use of highly sensitive and specific LC/MS/MS is increasing and has simplified some of the sample preparation procedures. 

Other simulation experiments performed in our laboratory include design of MIP adsorbents for solid-phase extraction of atrazine [77], DDT, lindane, aflatoxin Bl, ochratoxin A, and tylosin (unpublished data) and the development of assay/ sensor recognition elements for biotin (unpublished data) and creatinine [78]. In all these cases, molecular modeling proved to be a useful tool for MIP design. It would... 

Chen, C. Y, Li, W. J., and Peng, K. Y. 2005. Determination of aflatoxin Ml in milk and milk powder using high-flow solid-phase extraction and liquid chromatography-tandem mass spectrometry. J. Agric. Food Chem. 53 8474-8480. 

Alcaide-Mohna, M., Ruiz-Jimenez, J., Mata-Granados, J. M., and Luque de Castro, M.D. 2009. High through-put aflatoxin determination in plant material by automated solid-phase extraction on-line coupled to laser-induced fluorescence screening and determination by hquid chromatography-triple quadrupole mass spectrometry. J. Chromatogr. A 1216 1115-1125. 

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