Development of nanoparticulate sustained release oral drug delivery system for the antihyperglycemic with antihypertensive drug

The oral-sustained release dosage form containing Repaglinide (RPG, antidiabetic) and Diltiazem HCL (DIL, antihypertensive) loaded chitosan nanoparticles were prepared by the ionotropic gelation method. The chitosan concentration (A) and TPP concentration (B) were selected as independent variables while percentage drug loading of Repaglinide (Y1) and Diltiazem HCL (Y2) were chosen as the dependent variables. The RPG and DIL-loaded chitosan nanoparticles produced in this study were evaluated for drug-polymer interaction, surface morphology, encapsulation efficiency, drug loading, particle size and invitro drug release. The release of Repaglinide from the drug-loaded nanoparticles in a phosphate buffer (pH 7.4) solution was observed to be sustained over a period of 19 h (batch1) while Diltiazem showed sustained release behaviour over a period of 20 h in distilled water. FTIR analysis confirmed compatibility of the drug with excipients. Apparent particle size data showed that the particles were nano size with a low polydispersity index.