Использование метода многоволновой спектрофотометрии при контроле качества тизоля геля и метронидазола в новой мягкой лекарственной форме «Метронидазоль»

Abstract

Introduction. For the introduction of new medicines into medical practice, a mandatory stage is quality control, which includes determining the quantitative content of active components using modern methods of pharmaceutical analysis. Tizol gel, included in soft dosage forms, is an independent pharmacologically active agent, therefore it is important to evaluate its content in complex medicinal preparations. Aim. To develop a method for quantitative determination of tizol gel and metronidazole in a new semisolid dosage form «Metronidazole» using multiple-wavelength spectrophotometry. Materials and methods. Pharmaceutical substance metronidazole, tizol gel, «Metronidazole» ointment containing 5% nitroimidazole in a tizol base was used for analysis. The studies were performed on spectrophotometer SF-2000 by multiple-wavelength spectrophotometry in the UV region. On the basis of experimental data, the metrological parameters of the developed analytical technique were calculated. Results and discussion. Experimental studies allowed us to justify the use of an acetate buffer solution with pH = 4 as the optimum solvent for the spectrophotometric analysis of tisol gel and metronidazole in the mixture. Analytical wavelengths (238 nm for tisol gel, 316 nm for metronidazole) were selected according to the UV spectra of the drugs obtained. According to the results of quantitative determination of the components of the Metronidazole ointment, the content of medicines is within the limits: metronidazole from 0.4900 to 0.5219 g, tizol gel (in terms of the mass fraction of titanium) – 2.32–2.46%, which are acceptable according to regulatory documentation (FSF 42-3157-06, OFS.1.8.0001). Conclusion. Quantitative analysis of tisol gel in complex pharmaceutical preparations was proposed for the first time. The method of quantitative determination by multiple-wavelength spectrophotometry has been developed which allows to determine the content of tizol gel and metronidazole in a new semisolid dosage form «Metronidazole» with relative errors of the average result not exceeding ± 3.00%.