A normal phase HPTLC method for the quantitative determination of fumonisin B1 in rice

Summary A normal phase HPTLC method has been validated by spiking, in quadruplet, uncontaminated extract of rice with fumonisin B₁ over the range 0 to 16g/g. The method utilises solid phase extraction using strong anionic exchange (SAX) cartridges, uni-directional normal phase high performance thin layer chromatography (HPTLC), novel visualisation by dipping into a 0.16% acidic solution ofp-anisaldehyde and quantification by scanning fluoro-densitometry. Response was linear only over the range 0 to 5 g/g (0 to 125 ng/spot) where recoveries averaged 81% for rice. Weighted linear regression yielded a limit of detection of 0.25 g/g for rice. Coefficients of variance were 15.4, 5.3, 2.8, 3.5, and 0.9% at fumonisin B₁ levels of 0.20, 0.5, 1.0, 2.0 and 5 g/g respectively, demonstrating good precision. This method claims to be the first fully quantitative HPTLC method for determining fumonisin B₁ in rice.