![]() Analytical options are outlined from the simplest and fastest methods with the smallest instrument requirements, through separation methods, to the latest hyphenated techniques. The aim of this review is to provide a guide that summarizes worldwide aflatoxin regulations and analytical methods for determination of aflatoxins in different food and feed matrices, that helps in the decision to choose the most appropriate method that meets the practical requirements of fast and sensitive control of their contamination. At present, there are several analytical methods applied in practice for determination of aflatoxins. Because of the health risk and the official maximum limits of aflatoxins, there is a need for application of fast and accurate testing methods. In the case of dairy ruminants, after the consumption of feed contaminated with aflatoxins, aflatoxin metabolites may appear in milk. Aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) as well as aflatoxin G1(AFG1) and aflatoxin G2 (AFG2) occur in the contaminated foods and feed. For Permissions, please email: produced mainly by filamentous fungi Aspergillus flavus and Aspergillus parasiticus, are one of the most carcinogenic compounds that have adverse health effects on both humans and animals consuming contaminated food and feed, respectively. This review describes the most important aspects of forced-flow TLC, including how the set-ups are developed and also the progress of detection methods used. Optimal efficiency is composed by the doubled effect of flow resulting from the pump-forced mobile phase (convex profile of laminar flow) and capillary forces on the dry stationary phase (concave laminar flow). A simple and special rule characterizes the progress of mobile phase. Overpressured layer chromatography gives a widely used special chapter of forced-flow planar chromatography, a special bridge between high-performance liquid column chromatography and thin-layer chromatography (TLC). An internal force is capillarity, while gravity, electric field, a pump and centrifugal forces belong to external forces. Mobile phase progress in planar stationary phase can be evoked by either external or internal forces. The robustness of the procedure was also determined and found be critically dependent on the type of plate used (TLC or HPTLC). A calibration curve was constructed for each aflatoxin by plotting spot area against amount of aflatoxin applied to the plate. The DL of the method was 0.018, 0.100, 0.15, and 0.14 ng for aflatoxins G2, G1, B2, and B1, respectively. Depending on the aflatoxin analyzed the results of the investigation were: 0.20 1.7, 0.85 84%, RSD < 10%. The validation procedure included tests on specificity and determination of the retention factor (RF), resolution (RS), asymmetry (AS), linearity, accuracy, precision, detection limit (DL), and quantitation limit (QL) of the method. ![]() Before the separation an OPLC prewashing step was necessary this eliminated the time-consuming and costly clean-up steps of other chromatographic methods. ![]() ![]() OPLC was performed with chloroform-toluene-tetrahydrofuran, 15 + 15 + 1 (v/v), as mobile phase. Samples were extracted with 9:1 (v/v) acetonitrile-water and the extracts were filtered and evaporated to dryness. This paper describes validation of an OPLC procedure developed for the determination of aflatoxins B1, B2, G1, and G2 in wheat.
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