Physico-chemical and solid-state characterization of secnidazole

Secnidazole (hydroxy-2-propyl)-1-methyl-2-nitro-5-imidazole) is an antimicr obic agent. This drug has pharmacological activity against intestinal and h epatic amebiasis, giardiasis and vaginal trichomoniasis. This paper shows t he physicochemical parameters of secnidazole determined during a preformula tion study. The determination of the apparent partition coefficient and the profile of solubility in dependence of pH demonstrate the basic characteri stic of the drug. The dissolution assay was performed to evaluate its behav ior in water. For this purpose,a new spectrophotometric method, which was l inear from 5 to 15 mug/ml, sensitive, precise, accurate and selective, was validated to assay the bulk drug. The evaluation of higroscopicity revealed that the drug is unstable above 54% of relative humidity. Rheological prop erties, such as porosity, tapped and bulk densities and percentage of compr essibility were calculated. Results show a bad rheological characteristic f or this drug. DSC curves do not show any physical interaction between the d rug and the excipients in the compatibility studies. (C) 2000 Elsevier Scie nce S.A. All rights reserved.