高效液相色谱法用于右美沙芬缓释剂的研究

Study of Relative Bioavailability of a Controlled-Release Dextromethorphan in Man Using High Performance Liquid Chromatography

用高效液相色冷荧光检测技术研究了右美沙芬缓释剂在人体内的药代动力学，并与右美沙芬普通剂型相比较计算了右美沙芬缓释剂的相对生物利用度。

extromethorphan is a widely used and effective nonnarcotic antitussive. Currently,the immediate-re-lease oral formulation of dextromethorphan provides bronchodilation for a duration of 4 to 6h. Thus, thedrug rnust be taken three or four times a day to provide continuous bronchodilation. In order to providelonger duration of activity and thereby reduce the number of doses that must be taken daily,a 30 mg con-trolled-release tablet has been developed to allow twice daily dosing. This study was undertaken to comparethe bioavailability and pharmacokinetics of a new controlled-released dosage form of dextromethorphan withthe currently marketed immediate-released dosage form. Plasma concentrations of dextromethorphan were measured using a high performance liquid chromatog-raphy. After the addition of an internal standard(methylmorphine),plasma samples were made alkaline and-extracted with hexane. Dextromethorphan was separated on a cyano column(200× 4.6mm,5μ)using a mo-bile phase of acetortitrile/0.022 mo1lL NaAc buffer(20:80,V/V),pH2.75 and detected by fluorescence de-tection at an excitation wavvelength of 225 nm and an emission wavelength of 305 nm,with a limit of detectionof 1.0ng/mL.