MEPS as a rapid sample preparation method to handle unstable compounds in a complex matrix: determination of AZD3409 in plasma samples utilizing MEPS-LC-MS-MS.

The aim of the present investigation is to develop a simple, fast, and sensitive method for the determination of a new candidate drug, AZD3409, in rat, dog, and human plasma samples. AZD3409 is stable in aqueous solutions at low pH (< 4) but not in whole blood or in plasma. In rat plasma at 25 degrees C, more than 90% of the compound is degraded within 40 min.