title: Development and in-house validation of a microbiological assay for determination of cefepime in injectable preparations.
abstract: Cefepime is a new parenteral cephalosporin that has been described as a fourth-generation, broad-spectrum antibiotic. This paper reports the development and in-house validation of an agar diffusion bioassay using a cylinder-plate method for the determination of cefepime in powder for injection. The validation performed yielded good results in terms of linearity, precision, accuracy, and robustness. The assay is based on the inhibitory effect of cefepime upon the strain of Micrococcus luteus ATCC 10240 used as the test microorganism. The results of assays were treated statistically by analysis of variance (ANOVA) and were found to be linear (r = 0.99993) in the selected range of 8.0-32.0 microg/mL; precise [repeatability: relative standard deviation (RSD) = 1.39%, intermediate precision: between-day RSD = 1.77%, and between-analyst RSD = 1.97%] and accurate. Comparison of bioassay and liquid chromatography by ANOVA showed no significant difference between methodologies. The results demonstrated the validity of the proposed bioassay, which is a simple and useful alternative methodology for cefepime determination in routine quality control.
authors.affiliation: Centro de Desenvolvimentos de Testes e Ensaios Farmacêuticos (CTEFAR), DFI, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Santa Maria, Brazil.
authors.forename: Marines J
authors.initials: MJ
authors.lastname: Souza
authors.forename: Rosecler R
authors.initials: RR
authors.lastname: Kulmann
authors.forename: Lucélia M
authors.initials: LM
authors.lastname: Silva
authors.forename: Daniele R
authors.initials: DR
authors.lastname: Nogueira
authors.forename: Estevan S
authors.initials: ES
authors.lastname: Zimmermann
authors.forename: Cleber A
authors.initials: CA
authors.lastname: Schmidt
mesh_terms: D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology / Q000592:standards; D001681:Biological Assay / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D000077723:Cefepime; D002511:Cephalosporins / Q000008:administration & dosage / Q000032:analysis* / Q000494:pharmacology / Q000592:standards; D002853:Chromatography, Liquid; D007267:Injections; D013058:Mass Spectrometry; D016982:Micrococcus luteus / Q000187:drug effects; D011208:Powders; D012015:Reference Standards; D015203:Reproducibility of Results
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D011208:Powders; D000077723:Cefepime