1.Stability of cefepime dihydrochloride monohydrate in solid state.
Musiał W1, Zajac M. Acta Pol Pharm. 2002 Jul-Aug;59(4):243-6.
The pseudo first-order rate constants and thermodynamic parameters for the decomposition of cefepime in solid state in absence of humidity and at a relative humidity of 76.4% were calculated. The effect of humidity on the stability of cefepime dihydrochloride monohydrate in the humidity range 25.0%-76.4% at 358 K is described by the equation ln ki = (0.031 +/- 0.0043) x RH% - 10.08 +/- 0.22.
2.Identification and characterization of new degradation products of cefepime dihydrochloride
Jagadeesh Kumar V1, Badarinadh Gupta P, Pavan Kumar KS, Prasada Rao KV, Rao KR, Prasanna SJ, Kumar Sharma H, Mukkanti K. Anal Sci. 2010;26(10):1081-6.
The degradation products of Cefepime dihydrochloride that emerged throughout stress stability studies have been determined, identified and characterized. The two new impurities were detected by gradient reverse-phase high performance liquid chromatography (HPLC), and Impurity-I was formed in the range from 0.2 to 11.0% and Impurity-II range from 0.2 to 3.5%. These impurities have been identified by LC/MS, and were not reported in the literature. These impurities were synthesized, isolated and characterized. Based on the spectral data, the impurities were named (6R,7R)-7-[(Z)-2-(2-amino-4-thiazolyl)-2-(methoxyimino)acetamido]-3-[(1-methyl-1-pyrrolidinium)methyl]-3-cephem-4-carboxylate-1-oxide (Impurity-I); (2RS)-2[[(Z)-2-(2-amino-4-thiazolyl)-2-(methoxyimino)acetamido]-methyl]-1,2,5,7-tetrahydro-7-oxo-4H-furo[3,4-d][1,3]thiazine (Impurity-II). The structures were established unambiguously by independent synthesis and co-injection in HPLC to confirm the retention times and relative retention times.
