Physicochemical characterization & dissolution studies of Allopurinol

The rate-limiting step to absorption of drugs from the gastrointestinal tract is often dissolution from the dosage form. Allopurinol is a commonly used drug in the treatment of chronic gout or hyperuricaemia associated with leukaemia, radiotherapy. One of the major problems with allopurinol is that, it is practically insoluble in water, which results in poor bioavailability after oral administration. In the present study amphiphilic carrier like gelucire 50/13, PVP K30 & PEG 6000 are used in the ratio of 1:1, 1:2 and 1:4. Prepared solid dispersions were characterized in the liquid state by phase solubility studies and in the solid state by Differential Scanning calorimetric analysis, Powder X-ray diffractometry and Fourier Transform Infrared spectroscopy. The aqueous solubility of allopurinol was preferential by the presence polymer with increasing concentration. Solid state characterizations indicated that allopurinol was present as an amorphous material and entrapped in polymermatrix. Therefore, the current Research showed that gelucire 50/13 PVP K30 & PEG 6000 has a significant solubilizing effect on allopurinol.