Use of Microporous Accurel MP1000 for Duodenal Delivery of Secnidazole: A High Dose, Gastric pH Unstable Drug

Abstract

Secnidazole, a high dose antiprotozoal agent unstable at gastric pH was used as a model compound for deposition onto the adsorbent carriers by two methods namely solvent deposition and physical mixing for duodenal delivery. The drug/adsorbent systems were evaluated for pharmacotechnical properties and characterized by FT-IR, DSC, XRD, SEM and in vitro dissolution testing to investigate the influence of carriers and methods of preparation on in vitro drug release. The solvent deposited secnidazole adsorbates (F4-F6) with high drug loading capacity and better control on dissolution at all time points were subjected to modified release by encapsulating in formaldehyde treated PVP K40 coated capsules. The optimized formulation was able to maintain zero order release with a maximum release of 95.91% at the end of 8 h in contrast to marketed formulation that gave a burst release of 67.89% within 2.5 hours followed by a non zero order release of 87.89% at the end of fifth hour. Thus a formulation of secnidazole accurel adsorbates could be developed that when suitably designed provided controlled duodenal delivery.