Stability of cefsulodin in aqueous buffered solutions and some intravenous admixtures.

The stability of cefsulodin in aqueous solutions of various pH values, buffer concentrations, ionic strengths and intravenous admixtures were studied using a stability-indicating high-pressure liquid chromatography method. The pH range of optimum stability was determined to be 3.2-5.7. Cefsulodin was more stable on the acidic and less on the alkaline side as compared with most of the other cephalosporins such as cefoxitin (pH range of optimum stability approximately 4-7). In 5% dextrose and 0.9% sodium chloride injection, cefsulodin was stable (at least 90% potent) for about 1, 17 and at least 60 days at 24 degrees, 5 degrees and -10 degrees C, respectively.