Aim To establish a reversed-phase liquid chromatographic (LC) method forsimultaneous determination of tetramethylpyrazine (TMP) and aspirin in a new compound formulation.Methods Chromatographic separation of the two drugs was achieved on a Diamonsil C_(18) column, usinga binary mixture of methanol-1.5% acetic acid (35:65, V/V, pH = 3.1) as mobile phase at a flow rateof 1.0 mL·min^(-1). Results Separation was completed in less than 12 min. Benzoic acid was used asthe internal standard. Recoveries at levels corresponding to 80 % to 120 % of the label claim ofthe formulation ranged from 99.6 to 100.3 % for aspirin and from 99.9 to 101.3% for TMP. The linearrange was 12.6 - 150.9 μg·mL^(-1)(r= 0.9997, n = 5) for aspirin and 25.0- 300.0 μg·mL^(-1) (r =0.9999, n = 5) for TMP. Conclusion The method developed can be used for the simultaneousdetermination of TMP and aspirin in pharmaceutical preparations.
A rapid, accurate and sensitive HPLC method for the determination of bupropion hydrochloride in a new tablet formulation is described. Chromatographic separation of bupropion hydrochloride is achieved using a mobile phase consisting of methanol -0.01 mol·L -1 ammonium dihydrogen phosphate (80:20, v/v, pH 4.8) at a flow rate of 1.0 mL·min -1 on a Hypersil BDS C18 column. Absorbance is monitored at 251 nm where bupropion hydrochloride has maximum absorption in the mobile phase. The linear range of determination for bupropion hydrochloride is between 2.12 and 21.2 μg·mL -1. The proposed method was validated with respect to accuracy, precision, limits of detection and quantification and robustness, etc.
