Preparation and In-vitro and In-vivo evaluation of colon targeted delivery of antiamoebic drug: an approach to reduce dose

Secnidazole (SNZ) a potent antiamoebic drug requires high dose (1g) due to absorption in Upper Gastrointestinal Tract (GIT) causes serious side effects, The aim of present study was to develop a Pectin:Zn-acetate microspheres (PZM) targeted to colon. PZM were formulated by spray drying method, coated with different concentration of zinc acetate and evaluated for their size, shape, loading efficiency and swelling index. The in-vitro drug release study was assessed under pH dissolution condition resembling the stomach (pH 1.3 0.1HCL, with for 2 h), small intestine (pH 7.4 Phosphate buffer for 3 h) and colon (pH 7 Phosphate buffer with 2% rat cecal content up to 24 h) and 24 h in-vivo organ distribution study was performed on Sprague-dawley albino rats. The amount of drug from PMZ at different time interval was estimated by HPLC method. Coated PMZ shown regular shape (spherical), size (100 -500 μm), with negligible in-vitro release up to 3 h and In-vivo organ distribution study of coated PMZ show negligible concentration (8.12±0.15) of drug in stomach and intestine in first 6 h in compared to uncoated (50.82±0.85) and pure drug (98.68±0.68). The in-vivo GIT behaviour using X-ray imaging on Albino Rabbits showed site specific delivery of SNZ to colon which is site of infection. This may be help to minimizing the dose and the side effects of drug.