Design and Development of Crystallo-co-agglomerates of Ritonavir for the Improvement of Physicochemical properties.

INTRODUCTION: The aim of present study was to obtained crystallo-co-agglomerates of ritonavir to improve the solubility, dissolution rate and other physicochemical properties.


METHODS: Ritonavir agglomerates were prepared by crystallo-co-agglomeration (CCA) technique. Acetone–water containing HPMC K-15, PEG-6000, PVP K-30 was used as the crystallization medium. The agglomerates were evaluated for saturation solubility, micromeritic properties, yield and drug content. The agglomerates were also characterized by Fourier Transforms Infra-red Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRPD) and Scanning Electron Microscopy (SEM).
RESULTS: The growth of particle size and the spherical form of the agglomerates resulted in formation of products with good flow and packing properties. The improved compaction properties of the agglomerated crystals were due to the fragmentation which occurred during compression. DSC and XRD studies showed that ritonavir particles crystallized in the presence of HPMC, PEG-6000, PVP K-30 and diluents did not undergo structural modifications. The dissolution rate of ritonavir from the agglomerates could be controlled by the amount of included diluents, being enhanced as the latter was increased. Moreover, the results showed that when the diluents were included both intra-granularly and extra-granularly during agglomeration of ritonavir particles.
DISCUSSION AND CONCLUSION: Thus the crystallo-co agglomeration was successfully applied to improve the physicochemical properties of ritonavir.