P.A. Pangarkar, R. R. Thenge, N.M. Mahajan, V.S. Adhao, P.V. Ajmire

Abstract

Irbesartan is a non peptide specific competitive antagonist of the angiotensin II receptor used orally for treatment of hypertension. Irbesartan exhibits low bioavailability related to its poor water solubility. The present research carried out for crystal modification irbesartan in the presence of different additives, to improve the solubility and dissolution rate. The additives used for the crystal modification were PVP K30, PEG 4000, HPMC and Tween 80. The modified crystals were characterized by Scanning electron microscopy, FT-IR spectroscopy, differential scanning calorimetry and X-ray diffraction. The comparative solubility and dissolution rate of modified crystals and the untreated irbesartan were studied. The SEM results different morphology (size and shape) in the presence of additives. FT-IR spectra of untreated irbesartan when compared with the various crystals obtained in the presence of additives showed no significant change in their characteristic peaks. Also DSC spectra showed slight change in the melting endotherm of modified crystals and the XRD spectra revealed slight change in diffraction pattern. The FT-IR, DSC and XRD indicate crystal modification in the presence of additives. The modified crystals obtained in the presence of PEG 4000 showed maximum solubility and dissolution rate compared to other modified crystals and untreated irbesartan.