Preparation of Enteric Coated Pellets Containing Lansoprazole Using Extrusion/Spheronization Technique

Lansoprazole degrades rapidly in an aqueous solution at low pH values. Degradation rate increases at pH values below 4 .The aim of this study was development of enteric coated pellets containing Lansoprazole by an extrusion/ spheronization technique. Eight different formulations based on lactose and six different formulations based on mannitol, consisting of different portions of other excipients including sucrose, hydroxy propyl methyl cellulose, magnesium carbonate, and sodium lauryl sulfate have been prepared. Feret diameter, shape factor, and amount of drug released were determined for each formulation. Among different formulations, F14, which consists of mannitol, sucrose, HPMC, talc, magnesium carbonate, and lansoprazole, is considered to be the best formulation. Six other different formulations for the preparation of enteric coatings based on Eudragit S100, Eudragit L100, triethyl citrate, and talc were prepared and coating procedure on pellets (F14) was performed using coating pan. In vitro drug release tests in acidic media (pH=1.2) and buffer media (pH=6.8) were performed for pellets, coated with each coating formulation and dissolution profile for each formulation was prepared. The pellets coated by formulation F.C 4, consisting of Eudragit L 100, triethylcitrate, and talc, showed a proper in vitro drug release profile. Accelerated stability tests were performed on coated pellets according to USP, and data suggested that pellets will be stable for 2 years.