Nano-crystallization of flubendazole for enhanced dissolution rate and improved in vivo efficacy against Trichinella spiralis

Abstract

The aim was to enhance the dissolution rate and in vivo efficacy of flubendazole against trichinella spiralis. Flubendazole nanocrystals were developed by controlled anti-solvent recrystallization. Saturated flubendazole solution was prepared in DMSO. This was injected into phosphate buffer (pH 7.4) containing Aerosil 200, Poloxamer 407 or sodium lauryl sulphate (SLS) while mixing using paddle mixer. The developed crystals were separated from DMSO/aqueous system by centrifugation. The crystals were characterized using DSC, X-ray diffraction and electron microscopy. The crystals were suspended in Poloxamer 407 solution and dissolution rate was monitored. Optimal formulation was administered to Trichinella spiralis infected mice. Administration protocol attacked the parasite in intestinal, migrating and encysted phases. The crystals were spherical nanosized with formulation employing 0.2% Poloxamer 407 as stabilizer being optimum with size of 743.1 nm. DSC and X-ray supported particle size reduction with partial amorphization. Optimal formulation showed fast dissolution to deliver 83.1% after 5 min. Nanocrystals provided complete eradication of intestinal Trichinella and reduced larval count by 90.27 and 85.76% in migrating and encysted phases compared with marginal effect in case of unprocessed flubendazole. The efficacy was clearer from improved histopathological features of the muscles. The study introduced nano-crystallization for enhanced dissolution and in vivo efficacy of flubendazole.