“…For the determination of donepezil in human plasma, number of methods based on high-performance liquid chromatography (HPLC) (Yasui-Furukori et al, 2002;Mihara et al, 1993;Mahasen et al, 2006;Lee et al, 1992;Matsui et al, 1999a;Haginaka and Scyama, 1992;Nakashima et al, 2006) and liquid chromatographymass spectrometry (Matsui et al, 1995(Matsui et al, , 1999b(Matsui et al, , 2006Lu Y et al, 2004;Hao et al, 2003;Apostolou et al, 2007) have been described in recent years. The majority of these methods are based on liquidliquid extraction (LLE) using isopropyl alcohol:hexane (3:97, v/v).…”