Determination of Purines in Soybean Protein Isolate by Ultra High Performance Liquid Chromatography-Tandem Mass Spectrome-try
[Obiective]To establish a method for the simultaneous measurement of 4 purines in soybean protein isolate(SPI)using UPLC-MS/MS.[Method]Purines in SPI samples were hydrolyzed and extracted with trifluoroacetic acid:formic acid(V∶V=1∶1),and diluted with water.The 4 purines(guanine,adenine,hypoxanthine and xanthine)were then separated on an Agilent Poroshell 120 EC-C18 column,using 0.002%formic acid aqueous solution and methanol as mobile phases with gradient elution.Subsequently,the target compounds were analyzed with electrospray ionizationsource in positive ion mode under multi-reaction monitoring mode,employing the external standard quantitative method.[Result]Within the concentration range of 1-200 ng/mL,all four purines had good linear relationships,with correlation coefficients(r)exceeding 0.9991.The limits of quantitation(LOQ)and the limits of detection(LOD)for the four purines were in the range of 0.24-3.00 mg/kg and 0.08-1.00 mg/kg.The spiked experiments were performed at three concentration levels,and the average recovery rates for the four components ranged from 81.7%to 95.2%,with RSD all less than 8.6%(n=6).[Conclusion]This method is highly operable,simple and fast,with high sensitivity,recovery rate and precision,and can simultaneously detect four purine compounds in soy protein isolate.
Ultra performance liquid chromatography-tandem mass spectrometryPurineSoybean protein isolate
万方数据
维普
