Analysis and identification of the phosphopeptides in camel milk by MALDI-TOF MS

The MALDI-TOF MS-based method was establised for determining and identifing phosphopeptides in camel milk. The low abundance phosphopeptides of camel milk was enriched using commercial Ti O₂,and optimized the suitable adsorption-elution condition between the commercial Ti O₂ and camel milk,incubation buffer:acetonitrile/water(50/50,v/v) +1% trifluoroacetic acid,eluent:aqueous ammonia(10%). The obtained phosphopeptides solution was determined by MALDI-TOF MS method,and the data searching was carried out using Mascot database,four phosphopeptides was identified in the camel milk. This study provided a new idea for the phosphopeptides of different mammal milk determination and applied to the adulterated milk identification in the practical application.