Determination of aztreonam and L-arginine combination in parenteral formulations.

A rapid, sensitive and precise liquid chromatographic method is presented for the determination of aztreonam alone, in the presence of its degradation product, and in a parenteral formulation containing l-arginine. A reverse phase column and 0.2M phosphate buffer (pH 6)-methanol (95 + 5) with mobile phase at a flow rate of 2 mL/min is used. The method is sensitive for the range of 10-50 micrograms/mL with a relative standard deviation of less than 2%. The method has been applied to a parenteral formulation containing aztreonam and l-arginine. L-Arginine is also determined by a nonaqueous titrimetric method.

Liquid chromatographic determination of cinnamic and benzoic acids in benzoin preparations.

A liquid chromatographic method for the individual determination of benzoic and cinnamic acids in 2 benzoin preparations is presented. The method specifies a reverse phase column and 0.01M KH2PO4-methanol (85 + 15) as mobile phase at a flow rate of 1.8 mL/min, with detection at 254 nm. The method has been applied to 2 benzoin preparations and the results were compared with those from the British Pharmacopoeia method.

Rapid differential pulse polarographic determination of tiaprofenic acid.

Tiaprofenic acid (Surgam) has been determined directly by using differential pulse polarography (DPP) and pH 5.5 acetate buffer as a supporting electrolyte. The differential pulse polarogram was obtained under constant amplitude pulses of 50 mV superimposed on a linearly increasing dc ramp. Peak current was measured at the peak potential of -0.990 V vs Ag/AgCl reference electrode. Under the experimental conditions used, a linear relationship between peak current and concentration was established over the range 0.5-5.0 micrograms/mL. Mean percentage recoveries for tiaprofenic acid in authentic and tablet forms were 100.27 +/- 2.25 and 99.45 +/- 1.44, respectively. The results obtained by the DPP method were compared with those of the spectrophotometric method used by the manufacturer for the analysis of tiaprofenic acid and its tablet form.

Polarographic determination of butorphanol tartrate.

A new indirect polarographic method is proposed for the determination of butorphanol tartrate in the injectable solution form (Stadol). Direct-current polarography and differential pulse polarography (DPP) were applied for the study of authentic butorphanol and its injectable solution form in alkaline medium after nitration with 1 M potassium nitrite in presence of 1 M hydrochloric acid. The standard addition method was employed for the evaluation of the results and the mean percentage found for the injectable solution form was 99.2 +/- 1.0.