Broad-spectrum immunoaffinity cleanup for the determination of aflatoxins B 1 , B 2 , G 1 , G 2 , M 1 , M 2 in Ophiocordyceps sinensis and its pharmaceutical preparations by ultra performance liquid chromatography tandem mass spectrometry.

An ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of aflatoxins B1 , B2 , G1 , G2 , M1 and M2 (AFB1 , AFB2 , AFG1 , AFG2 , AFM1 and AFM2 ) in Ophiocordyceps sinensis and its pharmaceutical preparations. A rapid and reliable immunoaffinity column containing a broad-spectrum monoclonal antibody for six aflatoxins was used for sample cleanup. Under the optimized conditions, the home-made immunoaffinity column capacity were about 315, 319, 292, 102, 444 and 369ng/mL gel for AFB1 , AFB2 , AFG1 , AFG2 , AFM1 and AFM2 , respectively. Recoveries for all tested aflatoxins ranged from 79.28% to 103.42% with relative standard deviation less than 8%. The limits of quantitation were in the range of 0.008-0.045μg/kg. Among 31 real samples analyzed, one sample was contaminated with AFB1 , AFB2 and AFM1 at levels of 0.483, 0.068 and 0.104μg/kg, respectively. The established method is simple, accurate, and can be effectively used to determine the aflatoxins in Ophiocordyceps sinensis and its pharmaceutical preparations.