Abstract
Objective: The objective of the present research work for investigation of the physico-chemical, morphological and rheological properties of novel natural polymer, Araucaria heterophylla gum (AHG) and also investigate for its pharmaceutical applications as excipient. Hence, the present study was carried out to study its properties and applicability in the design of controlled release dosage forms. Methods: Diclofenac sodium matrix tablets prepared by wet granulation method. The tablets were compressed by using 10 mm punches. Drug-polymer compatibility studies were examined by Fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray diffraction studies. In vitro dissolution studies for formulations were carried out in 0.1N HCl (pH 1.2) was for the first 2 h and pH 6.8 phosphate buffer was used for remaining 24 h as dissolution medium. Results: The obtained results confirmed that the absence of interactions between the drug and polymers. AHD 8 showed 99.52% drug release in 24 h. Stability studies showed no significant change of AHG sample. Tablets prepared with AHG matrix tablets showed zero order drug release and follows the erosion mechanism. The weight variation of the tablets was complied with the compendia standards for uniformity of weight. The hardness, drug content and friability values for all the formulations found to be in the range as per IP. Conclusion: The powder characteristics of the AHG showed good flowing properties and other physico-chemical properties were suitable to be used as excipient in the formulation. FTIR, DSC and XRD studies of AHG were carried for characterization of the gum. The bacterial and fungal counts were within limits and pathogenic microorganisms were absent in AHG. Rheological properties of AHG suggested that it could be used as an excipient in controlled release system in particular to hydrophilic matrix tablet formulations. Hence, concluded that AHG is novel polymer for controlled release of dosage form.
