Abstract

Reversed-phase high performance liquid chromatography (RP-HPLC) methods were established for the simultaneous determination of ibuprofen (IBU) and diphenhydramine HCl (DPH) in orally disintegrating tablets (ODTs) and its dissolution in this work. The separation was performed on a Shim-pack VP-ODS C₁₈ (150 × 4.6 mm, 5 µm) column. The mobile phases of determination and dissolution were a mixture of 0.05 mol/L potassium dihydrogen phosphate buffer (containing 0.2% triethylamine and 0.2% glacial acetic acid)-acetonitrile (54:46, v/v) and a mixture of 0.05 mol/L potassium dihydrogen phosphate buffer-acetonitrile-triethylamine (60:40:0.2), respectively. The mobile phase was delivered at a flow rate of 1.0 ml/min, and the detection was carried out at 263 nm under the column temperature of 30°C and the injection volume of 20 µl. The linear ranges of determination were 100 to 1000 µg/ml with the correlation coefficient of 0.9996 for IBU and 7.5 to 120 µg/ml with the correlation coefficient of 0.9998 for DPH. The average recoveries (n = 9) were 98.52% (relative standard deviation (RSD) = 0.22%) for IBU and 99.07% (RSD = 0.87%) for DPH, respectively. The linear ranges of dissolution were 50 to 800 µg/ml with the correlation coefficient of 0.9999 for IBU and 5 to 80 µg/ml with the correlation coefficient of 0.9999 for DPH; the dissolution both exceeded 80% of the labeled at 10 min. The results showed that the proposed methods were simple, sensitive, accurate and specific. To evaluate its potential application value, IBU and DPH in compound ODTs were simultaneously detected using this approach, and satisfied results were obtained.

Key words: Ibuprofen, diphenhydramine hydrochloride (HCl), reversed-phase high performance liquid chromatography (RP-HPLC), determination, dissolution.