Fabrication and evaluation of pH-dependent polymeric microspheres of ivabradine and their in vitro and in vivo studies

The aim of this work was the development and evaluation of controlled release formulations consisting of methacrylate derivatives and ethyl cellulose synthesized using oil-in-oil solvent evaporation method. Drug release studies were performed in different dissolution media. Maximum drug released was observed at pH 7.4. Fourier transform infrared spectroscopy spectra, SEM and thermal analysis showed compatibility between drug and polymers. Pharmacokinetic parameters were calculated by Phoenix WinNonlin (R) version 6.3 software. The average AUC(0-t) was found to be 2483.71 +/- 13.173 ng/mlh, 5954.37 +/- 12.110 ng/mlh, 6400.82 +/- 19.131 ng/mlh and 7427.4 +/- 49.322 ng/mlh for group 1-4, respectively. The maximum concentration (C-max) of IBH for all groups predicted from pharmacokinetics data was 880.38 ng/ml, 718.43 ng/ml, 721.87 ng/ml and 805.11 ng/ml, respectively. Thus, in vitro and in vivo drug release studies of polymeric microspheres proved their controlled release behavior with preferential delivery for an extended period of time.