Abstract: A new pretreatment method was introduced into DMPK(drug metabolism and pharmacokinetic) studies, which was named MAS(multi-function Impurity Adsorption SPE), ultilizing some special adsorbents to remove the impurities, such as phospholipid. It has a better performance compared to traditional protein precipitation and SPE pretreatment. Combined with LC/MS, MAS can be applied in DMPK as a high throughput and effective pretreatment successfully.