Determination of Pregabalin R-Enantiomer in Pregabalin Bulk Drug by RP-HPLC with ELSD

RP-HPLC was applied to the determination of pregabalin R-enantiomer in pregabalin bulk drug with a chiral chromatographic column tendermed with an evaporative light scattering detector (ELSD). The chromatographic conditions were as follow: CHIRALPAK ZWIX(+) column (4.0 mm×150 mm, 3 μm) was used as seperation column with the column temperture of 25 ℃; the mobile phase was methanol-acetonitrile-water-formate-diethylamine (450+450+100+2.0+2.5) with the flow rate of 0.5 mL·min^-1; ELSD was used as the detector with the drift tube temperature of 70 ℃ and the flow rate of nebulizing gas of 2.0 L·min^-1. The linearity range of pregabalin R-enantiomer was 0.80-4.5 mg·L^-1, with detection limit of 0.30 mg·L^-1 and the lower limit of determination of 0.80 mg·L^-1. Recovery rates obtained by standard addition method were in the range of 93.8%-94.5%, and RSDs (n=6) were less than 2.5%.