Development and Evaluation of Microbaloons-based Extended Release Drug Delivery System for Hypertension Therapy

Abstract

The objective of the present work was to formulate and evaluate microballoons of captopril for prolongation of gastric residence time. The microballoons were prepared by the solvent diffusion technique using different ratio of ethyl cellulose, HPMCK4M & acrylic polymers as Eudragit RL100. Microballoons characterized for micrometrics properties found in passable to good range, the yield of microballoons was up to 71.20 ± 4.68 to 92.25 ± 2.34 % and % entrapment efficiency was found to be 71.40±1.64 to 87.34 ± 2.54 % respectively. The size of microballoons formulations was in the range of 159.1 ± 4.09 to 203.42 ± 5.61. The shape and surface morphology of prepared microballoons were characterized by scanning electron microscopy. The microballoons formed were additionally found to be floating over gastric juice for >12 hours. A broad range of drug release pattern could be achieved by varying the drug and polymer amount, the best results were obtained in F-4 formulation at the ratio of drug: polymer (1:1) containing HPMC K4M and Eudragit RL100 as a polymer exhibited prolong drug release over 12 hrs.  Higher values of correlation coefficients were obtained with Higuchi’s square root of time kinetic. The mechanism of the release of captopril from formulation was found to be Non-Fickian transport. Drug–polymers interaction has been determined based on FTIR studies. Optimized formulation (F-4) was stable up to 90 days prior storage at 40 ± 2 oC and 5-8 ± 2 oC in terms of % yield, %EE and % drug released.  No significant difference was observed in above analyzed parameters, supported by statistical tests. The developed floating microballoons of captopril might be clinically used for prolonged drug release in GIT, for better drug utilization and improved patient compliance.