Microbiological assay for quantitative determination of Imipenem in powder for injection

This work describes the development and validation of a microbiological method using the cylinder-plate assay for quantitative determination of imipenem in powder for injection. The aim was to obtain a low-cost and suitable methodology that can be alternative to physicochemical techniques already described, contributing for the quality control of this antibiotic. Firstly, the analytical conditions were optimized, testing the microorganism, inoculum concentration and best range of sample and standard concentrations, in a way that provides the adequate measurement of the inhibition halos. Staphylococcus epidermidis ATCC 12228 was selected as test microorganism, as well as 2.0 % of inoculum concentration. The validation protocol followed the official guidelines, and the parameters evaluated were linearity, precision (intermediate precision and repeatability) and accuracy. All standard curves ranging 0.5-2.0 μg/mL showed r values higher than 0.999, and ANOVA confirmed that were no deviation from linearity (p-value > 0.05). The method also proved to be precise with RSD (relative standard deviation) values ranging 0.28-0.64 for repeatability and 2.49 for intermediate precision. It was performed three days of experiments, being three assays of eight plates a day. The drug mean content was 101.05%. Accuracy was assessed by recovery test, with standard recovery percentage of 101.70-107.90% (mean recovery = 104.86%), which was considered satisfactory. Therefore, the proposed microbiological method was considered validated and suitable for application in quantitative determination of this drug, being useful for quality control routine

Microbiological assay for quantitative determination of the antibiotic imipenem in powder for injection

O presente trabalho aborda o desenvolvimento e validação de um método microbiológico utilizando o ensaio de cilindros em placas, para a determinação quantitativa do antibiótico imipenem na forma farmacêutica de pó para injeção. O objetivo do trabalho envolveu o estudo analítico de desenvolvimento de uma metodologia alternativa efetiva e de baixo-custo aos métodos físico-químicos já descritos, e aplicável na rotina de controle de qualidade deste antibiótico. Na etapa de desenvolvimento do método, foram otimizadas as condições analíticas, tais como: escolha do microrganismo teste, concentração do inóculo e faixa de concentração das soluções amostra e padrão, permitindo a adequada medição dos halos de inibição. Empregou-se Staphylococcus epidermidis ATCC 12228 como microrganismo teste, concentração do inóculo de 2%, e faixa de concentração de análise entre 0,5-2,0 μg/mL. O protocolo de validação seguiu as guias oficiais e os parâmetros avaliados foram linearidade, precisão (precisão intermediária e repetibilidade) e exatidão. No estudo da linearidade, todas as curvas padrão obtidas tiveram coeficiente de correlação superior a 0,999 e a ANOVA confirmou que não houve desvios de linearidade (p-valor < 0,05). O método mostrou-se preciso, com valores de DPR (%) na faixa de 0,28-0,64 (intra-dia), e de 2,49 (inter dias). Os experimentos foram realizados em 3 dias, sendo 3 ensaios com 8 placas por dia. O teor médio de imipenem foi de 101,05 %. A exatidão foi avaliada pelo teste de recuperação, com percentual recuperado de 101,70 - 107,90%, sendo considerado satisfatório. Dessa forma, o método proposto foi considerado validado e adequado à determinação quantitativa do imipenem em pó para injeção, sendo uma alternativa no controle de qualidade deste antibiótico.This work describes the development and validation of a microbiological method using the cylinder-plate assay for quantitative determination of imipenem in powder for injection. The aim was to obtain a low-cost and suitable methodology which can be an alternative to physicochemical techniques already described, contributing for the quality control of this antibiotic. Firstly, the analytical conditions were optimized, such as the choice of the test microorganism, inoculum concentration and best range of sample and standard concentrations, in a way that provides the adequate measurement of the inhibition halos. Staphylococcus epidermidis ATCC 12228 was selected as test microorganism, 2.0 % of inoculum concentration, and the analytical concentration ranging 0.5-2.0 μg mL-1. The validation protocol followed the official guidelines, and the parameters evaluated were linearity, precision (intermediate precision and repeatability) and accuracy. All standard curves obtained in linearity study showed r values higher than 0.999, and ANOVA confirmed that were no deviation from linearity (p-value < 0.05). The method also proved to be precise with RSD (relative standard deviation) values ranging 0.28-0.64 for repeatability and 2.49 for intermediate precision. It was performed three days of experiments, being three assays of eight plates a day. The drug mean content was 101.05%. Accuracy was assessed by recovery test, with standard recovery percentage of 101.70-107.90% (mean recovery = 104.86%), which was considered satisfactory. Therefore, the proposed microbiological method was considered validated and suitable for application in quantitative determination of this drug, being useful for quality control routine

UV spectrophotometric method for determination of posaconazole : comparison to HPLC

The aim of this work was to develop a simple, fast and reproducible spectrophotometric method for the analysis of posaconazole in raw material. The established conditions were: methanol as extracting solvent, detection wavelength of 260 nm, Shimadzu double beam spectrophotometer 1800 model with 1 cm quartz cells. Linearity was demonstrated in the concentration range of 5.0 a 25.0 μg/mL (r = 0.9999). Reproducibility and intermediate precision were confirmed by low RSD values (0.49 to 0.82%). Accuracy, evaluated through recovery test, was adequate, with 98.20% of mean recovery. Specificity and robustness were also demonstrated. The mean amount found for samples was 100.82%. The proposed method was considered suitable for the intended purpose, mainly in routine analysis of quality control laboratories. When compared to the previously developed HPLC, no statistical difference was observed, what made the UV spectrophotometric method a reliable alternative.O objetivo deste trabalho foi desenvolver um método espectrofotométrico simples, rápido e reprodutível para a análise de posaconazol na matéria-prima. As condições estabelecidas foram: metanol como solvente extrator, comprimento de onda de 260 nm e espectrofotômetro de duplo feixe Shimadzu, modelo 1800, com cubetas de quartzo de 1 cm. A linearidade foi demonstrada na faixa de concentração de 5,0 a 25,0 μg/mL (r = 0,9999). A reprodutibilidade e a precisão intermediária foram confirmadas pelos baixos valores de desvio padrão relativo (0,49 a 0,82%). A exatidão, avaliada pelo teste de recuperação, foi adequada, com recuperação média de 98,20%. A especificidade e a robustez também foram demonstradas. O teor médio encontrado nas amostras foi de 100,82%. O método proposto foi considerado adequado, principalmente para a análise de rotina em laboratórios de controle de qualidade. Quando comparado com o método por HPLC, não houve diferença estatística, o que torna o método por espectrofotometria UV uma alternativa segura

UV spectrophotometric method for determination of posaconazole : comparison to HPLC

The aim of this work was to develop a simple, fast and reproducible spectrophotometric method for the analysis of posaconazole in raw material. The established conditions were: methanol as extracting solvent, detection wavelength of 260 nm, Shimadzu double beam spectrophotometer 1800 model with 1 cm quartz cells. Linearity was demonstrated in the concentration range of 5.0 a 25.0 μg/mL (r = 0.9999). Reproducibility and intermediate precision were confirmed by low RSD values (0.49 to 0.82%). Accuracy, evaluated through recovery test, was adequate, with 98.20% of mean recovery. Specificity and robustness were also demonstrated. The mean amount found for samples was 100.82%. The proposed method was considered suitable for the intended purpose, mainly in routine analysis of quality control laboratories. When compared to the previously developed HPLC, no statistical difference was observed, what made the UV spectrophotometric method a reliable alternative.O objetivo deste trabalho foi desenvolver um método espectrofotométrico simples, rápido e reprodutível para a análise de posaconazol na matéria-prima. As condições estabelecidas foram: metanol como solvente extrator, comprimento de onda de 260 nm e espectrofotômetro de duplo feixe Shimadzu, modelo 1800, com cubetas de quartzo de 1 cm. A linearidade foi demonstrada na faixa de concentração de 5,0 a 25,0 μg/mL (r = 0,9999). A reprodutibilidade e a precisão intermediária foram confirmadas pelos baixos valores de desvio padrão relativo (0,49 a 0,82%). A exatidão, avaliada pelo teste de recuperação, foi adequada, com recuperação média de 98,20%. A especificidade e a robustez também foram demonstradas. O teor médio encontrado nas amostras foi de 100,82%. O método proposto foi considerado adequado, principalmente para a análise de rotina em laboratórios de controle de qualidade. Quando comparado com o método por HPLC, não houve diferença estatística, o que torna o método por espectrofotometria UV uma alternativa segura

Microbiological assay for quantitative determination of Imipenem in powder for injection

This work describes the development and validation of a microbiological method using the cylinder-plate assay for quantitative determination of imipenem in powder for injection. The aim was to obtain a low-cost and suitable methodology that can be alternative to physicochemical techniques already described, contributing for the quality control of this antibiotic. Firstly, the analytical conditions were optimized, testing the microorganism, inoculum concentration and best range of sample and standard concentrations, in a way that provides the adequate measurement of the inhibition halos. Staphylococcus epidermidis ATCC 12228 was selected as test microorganism, as well as 2.0 % of inoculum concentration. The validation protocol followed the official guidelines, and the parameters evaluated were linearity, precision (intermediate precision and repeatability) and accuracy. All standard curves ranging 0.5-2.0 μg/mL showed r values higher than 0.999, and ANOVA confirmed that were no deviation from linearity (p-value > 0.05). The method also proved to be precise with RSD (relative standard deviation) values ranging 0.28-0.64 for repeatability and 2.49 for intermediate precision. It was performed three days of experiments, being three assays of eight plates a day. The drug mean content was 101.05%. Accuracy was assessed by recovery test, with standard recovery percentage of 101.70-107.90% (mean recovery = 104.86%), which was considered satisfactory. Therefore, the proposed microbiological method was considered validated and suitable for application in quantitative determination of this drug, being useful for quality control routine

MICROBIOLOGICAL ASSAY FOR QUANTITATIVE DETERMINATION OF IMIPENEM IN POWDER FOR INJECTION

This work describes the development and validation of a microbiological method using the cylinder-plate assay for quantitative determination of imipenem in powder for injection. The aim was to obtain a low-cost and suitable methodology that can be alternative to physicochemical techniques already described, contributing for the quality control of this antibiotic. Firstly, the analytical conditions were optimized, testing the microorganism, inoculum concentration and best range of sample and standard concentrations, in a way that provides the adequate measurement of the inhibition halos. Staphylococcus epidermidis ATCC 12228 was selected as test microorganism, as well as 2.0 % of inoculum concentration. The validation protocol followed the official guidelines, and the parameters evaluated were linearity, precision (intermediate precision and repeatability) and accuracy. All standard curves ranging 0.5-2.0 µg mL-1 showed r values higher than 0.999, and ANOVA confirmed that were no deviation from linearity (p-value < 0.05). The method also proved to be precise with RSD (relative standard deviation) values ranging 0.28-0.64 for repeatability and 2.49 for intermediate precision. It was performed three days of experiments, being three assays of eight plates a day. The drug mean content was 101.05%. Accuracy was assessed by recovery test, with standard recovery percentage of 101.70-107.90% (mean recovery = 104.86%), which was considered satisfactory. Therefore, the proposed microbiological method was considered validated and suitable for application in quantitative determination of this drug, being useful for quality control routine

Biotransformation of metronidazole by Cunninghamella elegans ATCC 9245

Drug biotransformation studies appear as an alternative to pharmacological studies of metabolites, development of new drug candidates with reduced investment as well as the most efficient production of chemical structures involves and drug quality control studies. A wide range of reactions in biotransformations process are catalyzed by microorganisms. Fungi can be considered as a promising source of new biotransformation reactions. The aim of this study was to evaluate the capacity of metronidazole biotransformation through the filamentous fungus Cunninghamella elegans ATCC 9245. The monitoring of metabolite formation was performed by high-performance liquid chromatography (HPLC) coupled to ultraviolet (UV) spectrophotometry. The results of the biotransformation of metronidazole showed drug consumption in culture and formation of four new chromatographic peaks of chemical structures not elucidated. The method showed it became linear over 10-70 μg/mL (r = 0.999953). Accuracy, precision and stability studies agree with international guidelines. Results are consistent in accordance to the principles of green chemistry as the experimental conditions had a low environmental impact, and little use of environmental harmful solvents