ABSTRACT: The purpose of this study was to investigate the polymorphism and compatibility of benznidazole (BNZ), a drug used in the
treatment of Chagas disease. This drug was subjected to a polymorphic screen using a number of solvents and precipitation
procedures to explore the possible existence of different crystal structures of BNZ. The compatibility of BNZ with selected
pharmaceutical excipients was evaluated in binary mixtures, in a ratio of 1:1 (w/w). These results were then analyzed with
a variety of techniques, including differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray powder
diffractometry. No polymorphic forms of BNZ were detected despite some observed changes in the DSC profile. The thermal data
indicate interaction of the drug with excipients hydroxyethylcellulose, polyethylene glycol, and hydroxypropyl-β-cyclodextrin.
Additional studies using infrared spectroscopy confirm the incompatibility of BNZ with only the polyethylene glycol. This
excipient should not be used in the development of solid dosage forms containing BNZ.
KeywordsBenznidazole–Compatibility–Differential scanning calorimetry–Fourier transform infrared spectroscopy–Polymorphism–X-ray powder diffractometry
Journal of Thermal Analysis and Calorimetry 04/2012; 106(3):819-824. · 1.60 Impact Factor