Rapid Solid-Phase Extraction Method to Quantify 11C-Verapamil and its 11C-Metabolites in Human and Macaque Plasma

摘要

IntroductionP-glycoprotein (P-gp), an efflux transporter, is a significant barrier to drug entry into the brain and the fetus. The Positron Emmison Topography (PET) ligand, [¹¹C]-verapamil, has been used to measure in vivo P-gp activity at various tissue-blood barriers of humans and animals. Since verapamil is extensively metabolized in vivo, it is important to quantify the extent of verapamil metabolism in order to interpret such P-gp acitivity. Therefore, we developed a rapid solid phase extraction (SPE) method to separate, and then quantify, verapamil and its radiolabeled metabolites in plasma.