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.