Concentration and extraction of sinomenine from herb and plasma using a molecularly imprinted polymer as the stationary phase

A sinomenine (SIN) molecularly imprinted polymer (MIP) with specific recognition ability for SIN was prepared by in situ molecularly imprinted technique. The polymer was then packed into a polypropylene column and used as a solid-phase extraction (SPE) sorbent. Utilizing this MIP-SPE as the separation medium, a crude extract of SIN from Sinomenium acutum Reht. et Wils was purified, and relatively pure SIN was obtained. At the same time, based on the specific molecular recognition ability of MIP, a determination method of SIN in blood was established with MIP as the separation medium. The linear range was 5–60 μg ml−1, and the linear correlation coefficient of the standard curve was 0.9975. The average recovery was 98%, with the relative standard deviation (R.S.D.) 7% (within-day) and 8% (between-day). These results reveal that the established method can be used for analysis of SIN in biological samples.