ABSTRACT
Unfractionated heparins are used clinically as anticoagulants. The biological potency of thirteen samples of raw material and pharmaceutical formulations were assessed utilizing the 5th International Standard of heparin using the sheep plasma coagulation inhibition assay, activated partial thromboplastin time, anti-factor Xa assay, and anti-factor IIa assay, resulting in mean potencies of 101.15 percent, 96.15 percent, 98.15 percent and 99.37 percent, respectively. The samples were also evaluated by the protamine neutralization test giving results within the range of 92 - 138 IU/mg. The anti-factor IIa assay was performed showing reproducibility and significant correlation with the pharmacopoeial assays, thus demonstrating it to be a feasible alternative to the sheep plasma coagulation inhibition assay. Moreover, an analysis by nuclear magnetic resonance and capillary electrophoresis showed some peaks attributable to oversulfated chondroitin sulfate. The results show that batch-to-batch variations and the quality of samples contributed to improvements in the quality control of pharmaceutical products and to assure the safe use and clinical efficacy of this biological medicine.
As heparinas não fracionadas são utilizadas clinicamente como anticoagulantes. A potência biológica de 13 amostras de matérias-primas e produtos farmacêuticos foram avaliadas em relação ao 5ª Padrão Internacional de heparina pelos ensaios da inibição da coagulação do plasma ovino, tempo de tromboplastina parcial ativada, anti-fator Xa e anti-fator IIa, que forneceram potências médias de 101,15 por cento, 96,15 por cento, 98,15 por cento e 99,37 por cento, respectivamente. As amostras foram também submetidas ao teste de neutralização pela protamina que apresentou resultados entre 92-138 UI/mg. Demonstrou-se reprodutibilidade e correlação significativa do ensaio do anti-fator IIa com os farmacopeicos, constituindo-se em alternativa ao ensaio da inibição da coagulação do plasma ovino. Além disso, as análises realizadas por ressonância magnética nuclear e eletroforese capilar mostraram picos correspondentesà condroitina supersulfatada. Os resultados mostraram variações lote-a-lote e a qualidade das amostras contribuindo para aprimorar o controle de qualidade dos produtos farmacêuticos e garantir a segurança e eficácia terapêutica desses produtos biológicos.
Subject(s)
Animals , Blood Coagulation , Blood Coagulation Tests , Heparin , Partial Thromboplastin Time , SheepABSTRACT
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.
