Solid-phase extraction of matrine and oxymatrine from Sophora Flavescens Ait using amino-imidazolium polymer

A new, polymer-confined, ionic liquid sorbent was developed by a process involving polymerization and modification. The obtained particles were successfully used as a special sorbent in SPE process to isolate matrine and oxymatrine from Sophora Flavescens Ait. Different washing and elution solvents, such as ethanol, methanol, acetonitrile and methanol/triethylamine (90:10, v/v), were evaluated. Compared with the C-18 and NH2 sorbents, the amino-imidazolium polymer sorbent exhibited higher selectivity. Quantitative analysis was carried out by using a C-18 column. The two compounds exhibited good linearity from 5 x 10(-3) to 0.50 mg/mL (r(2)>0.99). The bound amounts between target compounds and proteins were obtained by this sorbent. After three recycles of amino-imidazolium polymer, the extract amounts of the target compounds were not significantly decreased.