Doseamento microbiológico de gentamicina por difusão em agar - proposta de delineamento experimental / Microbiological assay of gentamicin sulfate by agar diffusion - proposal of experimental design

AUTOR(ES)
DATA DE PUBLICAÇÃO

2006

RESUMO

Gentamicin is a broad-spectrum antibiotic complex produced by actinomycetes belonging to Micromonospora genus and classified among aminoglycoside antibiotics, used in the treatment of serious infections derived from Gram-negative microorganisms. Alterations of their antimicrobial activity not shown in chemical assays can be evaluated through microbiological assays. The aim of this work was to compare 5 x 1, 2 x 2 and 3 x 1 experimental designs, evaluating validation parameters of specificity, linearity, range, precision, and accuracy for each experimental design in different levels of concentration, presentation, and lots. It consisted of 81 assays (in 3 replicas) of gentamicin microbiological dosage. The concentrations of the solutions used were employed in a range from 1.0 µg/ml to 5.0 µg/ml, diluted in phosphate buffer 0.1 M pH 8.0. Antibiotic medium number 11 was used, with Staphyloccocus epidermis (ATCC 12228)21ml of medium were used as base layer and 4 ml of medium inoculated at 1% were used as surface layer. The plates were incubated for 16-18 hours at 37 ± 1 ºC. The three designs employed showed adequate specificity for analysis of dermatological cream and injectable solution containing gentamicin sulphate. They also showed accuracy and linearity in the range evaluated, but not a significant difference concerning precision. The results were compared by means of the determination of the rates of measurement system capacity. The statistical analysis demonstrated that there is no significant difference among the results obtained.

ASSUNTO(S)

method validation gentamicin sulfate validação de método microbiological assay doseamento microbiológico sulfato de gentamicina delineamento experimental experimental design

Documentos Relacionados