FOURIER TRANSFORM INFRARED SPECTROSCOPY, THERMOGRAVIMETRIC ANALYSIS, SCANNING ELECTRON MICROSCOPY AS SUPPORTING TOOLS IN QUALITY CONTROL OF ANTIPARASITICS

This study shows that Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) can be used as supporting tools for the evaluation of the quality of antiparasitics. In addition, an analytical methodology was developed and validated to quantify simultaneously thiabendazole (TB), febantel (FB), toltrazuril (TZ), and fluazuron (FZ) in bulk and in their veterinary pharmaceutical formulations using reverse phase high performance liquid chromatography (RP-HPLC). In order to investigate stability, pharmaceuticals were submitted to degradation processes under different conditions, such as recommended by the International Conference on Harmonization. The chromatographic conditions were optimized and the validation parameters, such as selectivity, linearity, detection limit, quantification limit, precision, accuracy, and robustness showed results within acceptable standards. All analytes were stable in the stability assays in acid and basic media and thermal conditions, except in the oxidation process, which presented two degradation peaks. Physicochemical characterization by TGA, FTIR, and SEM of raw materials of TB, FB, TZ, and FZ provided information about the authenticity of the analytes, proving the wide applicability of the instrumental techniques. The RP-HPLC proposed method was found to be accurate, precise, and reproducible and can in addition be used for routine quality control analysis.