Furosemide - Soluplus® Solid Dispersion: Development and Characterization.

Recent patents reveal that Soluplus® has proved to be a promising excipient that modulates dissolution characteristics of many active pharmaceutical ingredients (WO 2016161995 A1, WO 2016169534 A1, WO 2016165676 A1). Current article investigate on stable solid solution of furosemide with Soluplus to enhance the dissolution properties of the drug. Drug:carrier ratios to prepare solid dispersion was selected based on the phase solubility study. Solid dispersions of furosemide with Soluplus® were prepared by solvent evaporation and fusion method. Physico-chemical parameters were characterized using FTIR spectrophotometer, TGA, DTA, and SEM. Drug release from the formulations were compared using USP type II (paddle type) dissolution apparatus containing 900 mL of phosphate buffer (pH - 6.8) maintained at 37±ºC at a paddle rotation speed of 50 rpm. FTIR spectroscopy confirmed absence of any chemical interaction while DSC, DTA and TGA showed evidences of formation of a solid solution of furosemide. No furosemide crystals were observed under SEM in case of solid dispersion. Dissolution data indicated that furosemide dissolution was enhanced to a great extent and drug:carrier ratio of 1:10 was found to be most suitable. Solid dispersions prepared by fusion method exhibited faster drug release compared to those prepared by solvent evaporation.