Studies on Influence of Process and Formulation Variables on Performance of Omeprazole Pellets

The objective of the present study is to formulate and evaluate delayed release pellets of Omeprazole and to protect the drug from gastric fluids. The pellets were processed by employing FBC. The drug and excipient interaction studies were conducted with IR spectral studies and drug and the selected excipient were found to be compatible. Various process variables such as inlet air temperature, pump RPM, atomization air pressure, %damper opening, spray rate and formulation variables such as the concentration of alkalizing agent CaCo3, surfactant SLS and binder PVP in drug loading, the concentration of sub coating material HPMCE5 in barrier coating and the enteric coating material eudragitL30D55,the plasticizer PEG6000 were studied. The parameters such as exhaust air temperature, product temperature, physical appearance, size and size distribution, drug content, friability, acid resistance, moisture content and drug release were monitored during the study. Processing was found to be better when the inlet air temperature (50-600c), spray rate (1-6rpm), %damper opening (6.5-7) and atomized air pressure (1.8 kgcm2) were maintained. The optimized concentrations of CaCo3, SLS and PVP were found to be 0.235%, 0.033%, 0.019% respectively for drug loading.0.947%w/w HPMCE5 was found to be suitable for barrier coating and0.0874%w/w eudragitL30D55, 0.0322%PEG6000, 0.0051% NaOH was found to be optimum for enteric coating. The finished dosage form was subjected to short term stability studies as for ICH guidelines and optimized formulation was found to be quite stable.