This paper describes validation of an OPLC procedure developed for the determination of aflatoxins B1, B2, G1, and G2 in wheat. Samples were extracted with 9:1 (v/v) acetonitrile-water and the extracts were filtered and evaporated to dryness. OPLC was performed with chloroform-toluene-tetrahydrofuran, 15 + 15 + 1 (v/v), as mobile phase. Before the separation an OPLC prewashing step was necessary; this eliminated the time-consuming and costly clean-up steps of other chromatographic methods. 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. Depending on the aflatoxin analyzed the results of the investigation were: 0.20 < RF < 0.60, RS > 1.7, 0.85 < AS <1.1, recovery > 84%, RSD < 10%. The DL of the method was 0.018, 0.100, 0.15, and 0.14 ng for aflatoxins G2, G1, B2, and B1, respectively. A calibration curve was constructed for each aflatoxin by plotting spot area against amount of aflatoxin applied to the plate. The robustness of the procedure was also determined and found be critically dependent on the type of plate used (TLC or HPTLC).
|Number of pages||5|
|Journal||Journal of Planar Chromatography - Modern TLC|
|Publication status||Published - Dec 1 2000|
ASJC Scopus subject areas
- Analytical Chemistry
- Clinical Biochemistry