Ultra-performance liquid chromatography/tandem mass spectrometry for the simultaneous analysis of aflatoxins B1, G1, B2, G2 and ochratoxin A in beer.

The simultaneous analysis of aflatoxins B1, G1, B2, G2 and ochratoxin A in beer was carried out by ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS). Mycotoxins were extracted, purified and concentrated from the beer sample in one step using a solid-phase extraction (SPE) cartridge that contained a polymeric sorbent. Optimization of different parameters, such as type of SPE sorbent, type and amount of wash solvent and pH of the sample, was carried out.

Two-dimensional thin-layer chromatographic method for the analysis of ochratoxin A in green coffee.

A low-cost thin-layer chromatographic method has been developed for the presumptive measurement of ochratoxin A (OTA) at 5 microg/kg in green coffee beans. The analytical method consisted of extracting OTA by shaking the beans with a mixture of methanol and aqueous sodium bicarbonate solution, which was then purified by liquid-liquid partition into toluene. OTA was separated by normal-phase two-dimensional thin-layer chromatography and detected by visual estimation of fluorescence intensity under a UV lamp at 365 nm.

Determination of aflatoxins B1, G1, B2 and G2 in medicinal herbs by liquid chromatography-tandem mass spectrometry.

An easy method for the determination of aflatoxins B1, G1, B2 and G2 in Rhammus purshiana by LC coupled to mass spectrometry has been developed. Aflatoxins were extracted with a mixture of methanol and water and then it was purified by solid-phase clean-up using a polymeric sorbent, not described previously, for the determination of these toxins. The eluted extract was injected into the chromatographic system using a reversed-phase C18 short column with an isocratic mobile phase composed of methanol-water (30:70).

Analysis of ochratoxin a in coffee by solid-phase cleanup and narrow-bore liquid chromatography-fluorescence detector-mass spectrometry.

A method for the analysis of ochratoxin A (OTA) in green and roasted coffee has been developed. OTA was extracted from coffee with 1% NaHCO(3), and the extract was filtered and purified by solid-phase cleanup using a polymeric column that exhibits reversed-phase and anion-exchange functionalities. OTA was analyzed on a narrow-bore reversed-phase C(18) HPLC column with acetonitrile/water (0.