Avaliação da estabilidade de soluções padrões de amoxicilina e clavulanato de potássio utilizados na rotina do controle de qualidade

Abstract

Generic-drug law in Brazil was enacted on February 10, 1999, having great importance for increasing access of low-income population to quality treatment with low cost. In this context, there are innumerous drugs available on market, such as amoxicillin associated with potassium clavulanate, which belongs to the pharmacological class of β-lactams. This represents about 30% of the pharmaceutical industry's market share, having been widely used as a therapeutic option for treatment of respiratory tract infections. Faced with these facts, the pharmaceutical industry needs to guarantee the quality of drugs, for this reason are numerous resolutions from regulatory agencies, for example, Anvisa´s RDC 166 in Brazil, which suggest how to carry out analytical method validation with the purpose of guaranteeing dug’s quality. However, this resolution does not address the study of solution´s stability as mandatory, being this only one step in the study of robustness. Thus, the aim of the present study is to evaluate the stability of the standard solution of amoxycillin and potassium clavulanate from Prati-Donaduzzi pharmaceutical industry’s dosing method. On this way, two storage conditions were chosen: laboratory oven and refrigerator. In this context, standards were injected over time into a high-pressure liquid chromatograph in order to evaluate controls recovering faced with the initial curve, which should be in the range between 98.5 - 101.5 % to be considered stable. In addition, further identification tests were performed, such as UV and Raman spectra. They were evaluated in order to confirm standard degradation while stability’s study showed that they were no longer stable. On the one hand, these results showed that amoxicillin and potassium clavulanate standard were stable at 5 hours at laboratory oven condition and at 47 hours under refrigerator condition. In this context, during of high-pressure liquid chromatography assay were observed two impurities on laboratory oven condition, those were increasing their areas over time. Moreover, the UV spectra suggested they were degradation from potassium clavulanate at laboratory stove condition. In contrast, Raman technique was not possible to evaluate due to standard´s dilution. Thus, to sum up standards solution under this study showed greater stability at refrigerator storage than at laboratory oven condition.