Determination of 5 Kinds of Selenium Species in Livestock and Poultry Meat With Ion Pair Reversed Phase Liquid Chromatography-Atomic Fluorescence Spectrometry

A method of ion-pair reversed phased liquid chromatography-ultraviolet (IP-RP-HPLC)-hydride generation-atomic fluorescence spectrometry AFS) was established to determine the contents of selenocystine, methylselenocysteine, selenotmethionine, selenateand selenite in livestock and poultry meat. Organic Se species contents in samples were extracted by trypsin and protease (XIV, pronase) , and inorganic Se species contents in samples were extracted with iodine acetamide solution and water incubated at 55 degrees C with shaking at 200 r . min(-1) for 20 h. The extraction solution of samples was centrifuged at high speedand then centrifuged with microsep for purification. C18 separated the solution of samples reversed phase column by using 30 mmol . L-1 diammonium hydrogen phosphate, 0. 5 mmol . L-1 tetrabutyl-ammonium bromide and 5% (V/V) methanol as moblie phase. The pH of the mobile phase was adjusted to 6. 0 by 20% (WV) formic acid. IP-RP-HPLC-AFS determined the contents of five Se species in samples solution. The impurities are qualitatively determined by contrasting with the standard sample and quantitatively determined by calculating the peak areas. Selenocystine, methylselenocysteine, selenotmethionine, selenate and selenite had good linearities in the range of 5 similar to 200 mu g . L-1, and the correlation coefficients were all greater than 0. 999, the detection limits of five Se species were 0. 89, 0. 78, 0. 55, 0. 94 and 0. 70 mu g . L-1, respectively. There coveries were between 76. 8% similar to 109% , the within-run precisions and between-run precisions were 2. 7% similar to 6. 8% and 3. 5% similar to 12. 3% respectively. The proposed method has the advantages of rapid, simple, high sensitivity and high accuracy, and it is suitable for Se species analysis in livestock and poultry meat samples.