Objective: To establish an HPLC method for the separation of optical isomers of palonosetron hydrochloride by RP-HPLC with HP-β-cyclodextrin ( HP-β-CD) as the chiral additive. Methods:The optimal separation process was performed on a Shi-seido CAPACELL PAK C18 VG 120 (250 mm × 4. 6 mm,5μm) column,the mobile phase was triethylamine (TEA) with HP-β-CD at different concentrations, the pH value was adjusted by acetic acid, the detection wavelength was 240nm, and the column temperature was 30℃. Results:The mobile phase was 0. 5% TEA (1% HP-β-CD, adjusting pH to 5. 5 with acetic acid)-acetonotirile (85∶15);the detection wavelength was 240nm, and the flow rate was 0. 5 ml·min-1 . The S, R-Isomer of palonosetron hydrochloride could be well separated. Conclusion:The method can be used as the optical isomer quality control for palonosetron hydrochloride.

Objective:To establish an HILIC-HPLC-ELSD method for the determination of allantoin in Rhizoma Dioscoreae. Methods:The separation was performed on a Waters XBridge HILIC column(150 mm × 4. 6 mm,5μm),the mobile phase was ace-tonitrile-water(85:15)with the flow rate of 0. 8 ml·min-1 ,and the nebulizer pressure was 40psi,the drifting tube temperature was 80℃ and the nebulizer temperature was 50℃. Results:The linearity of allantoin was good within the range of 1. 5-7. 5 μg( r =0. 998 1). The regress equation was Y=1. 67X+2. 35,the detection limit was 25 ng,and the average recovery of allantoin in Rhizoma Dioscoreae was 99. 9% with RSD of 0. 72%(n=9). Conclusion:The method is simple and reliable,which can be used in the deter-mination of allantoin in Rhizoma Dioscoreae.