ROSIN MICROSPHERES AS TASTE MASKING AGENT IN ORAL DRUG DELIVERY SYSTEM

Natural resources in general and plant materials in particular are receiving more attention due to their safety as pharmaceutical excipients. Present work assessed the combination potential of natural hydrophobic resin, rosin, and synthetic polymer ethyl cellulose to mask the abhorrent inherent taste of ambroxol hydrochloride, by microencapsulation technique, and its possibility to formulate as a fast dissolving dosage form. Being of natural origin, rosin and its derivatives are biodegradable and biocompatible. Although It has excellent film forming property the native rosin films are brittle and break easily upon handling. The film forming properties of rosin was modified by substituting  a part with ethyl cellulose.The prepared rosin-ethyl cellulose composite microspheres by emulsion solvent evaporation technique possessed good sphericity, smooth surface morphology, uniform and narrow size distribution (10-90 µm), when analyzed by scanning electron microscopy. PEG 400 was used as plasticizer because of its hydrophilicity, biocompatibility and their excellent plasticizing activity. Method of preparation has influenced the particle size and drug loading efficiency. Drug-polymer compatibility was confirmed by Fourier transform infrared spectroscopy and thin layer chromatography. DSC studies revealed that the drug was molecularly dispersed inside the microspheres in the form of solid solution. Sensory studies in healthy human volunteers indicated that the taste and palatability were significantly improved by microencapsulation. This study demonstrated that rosin could be a right choice in developing patient favored formulations for bitter drugs and can be utilized in fast disintegrating dosage forms as well.