抄録
The stability of sodium latamoxef (Shiomarin; LMOX) in aqueous solution, a newly developed oxacephem antibiotic for injection, was tested at 5°, room temperature (20±5°), and 37°. Decomposition products were studied with thin-layer chromatography, bioautography and spectrophotometry. Furthermore, the residual potency was determined by a microbiological assay (cylinder-plate method). The results were as follows:
1) LMOX (1g (potenty)/10ml) aqueous solution showed changes in color, without any variation in pH after 7 days. Its residual potency after 7 days was 95.1%. The residual potencies after 24 hours were 99.0% at 5° with increased color intensity, 96.5% at 20° and 82.6% at 37°. 2) Aqueous solution of LMOX showed no color change at pH 3.60, but developed a light brown color at pH 8.00 and a light blue color at pH 10.00. No decrease in potency was observed after 24 hours at pH 3.60-10.10 at 5° or pH 3.60-9.00 at 20° and after 6 hours at pH 3.60-10.00 at 37°.
