Simultantous determination of ephedrine hydrochloride,diphenhydramine and dexame thasone sodium phosphate in the drops by HPLC

OBJECTIVE To establish a method for simultaneous determination of ephedrine hydrochloride , diphenhydramine and dexamethasone sodium phosphate in nose drops by HPLC. METHODS Ephedrine hydrochloride,diphenhydramine and dexamethasone sodium phosphate were eluted with CHOH 3- 0.05 mol·L -1 KH 2PO 4(CH 3CH 2)3N(58∶42∶ 0 .2 ) on C 18 column and detedted at 221 nm. The pH of the mobile phase was adjusted to 3.0 with phosphoric acid. RESULTS The linear range was 1600～2400 mg·L -1 (r=0.9994), the average recover y was 99.8% , RSD= 1.0% for ephedrine hydrochloride, The linear range was 80～120 mg·L -1 (r=0.9996),the average recovery was 101.3% ,RSD= 0. 9% for diphenhydramine, The linear range was 160～240 mg·L -1 (r= 0. 9991 ),the average recovery was 99.6% ,RSD= 0.8% for dexamethasone sodium phosphate.CONCLUSIONS This method was accurate for simultaneous determination of the three components in nose drops.