Surfactant-enhanced emulsification liquid-liquid microextraction combined with sweeping micellar electrokinetic chromatography-tandem mass spectrometry for therapeutic drug monitoring of alpelisib and fulvestrant in human plasma
摘要
A novel bioanalytical method combining surfactant-enhanced emulsification liquid-liquid microextraction (SE-LLME) with sweeping micellar electrokinetic chromatography-tandem mass spectrometry (MEKC-MS/MS) was developed and validated for therapeutic drug monitoring (TDM) of alpelisib (ALP) and fulvestrant (FUL) in human plasma. This method addresses the need for sensitive, selective quantification in patients with PIK3CA-mutated, HR+/HER2− breast cancer. Sample preparation involved protein precipitation followed by SE-LLME using pentadecafluorooctanoic acid (PFOA) and chloroform, yielding recoveries greater than 88.4% for ALP and 78.7% for FUL. Optimised MEKC conditions were 50 mM ammonium pentadecafluorooctanoate at pH 9.75 with 25% methanol, 30 kV separation voltage, 30 °C capillary temperature, and 100 mbar additional pressure during the analysis. Sweeping preconcentration significantly enhanced sensitivity—109-fold for ALP and 11.2-fold for FUL. The method was validated per ICH guidelines, demonstrating excellent linearity (