Investigation the Effect of Wet Granulation and Hydrophilic Binder in Dissolution of Felodipine

Abstract

The present study aimed to investigate the effect of wet granulation and hydrophilic binder concentration on the dissolution behavior of felodipine, a poorly water-soluble antihypertensive drug. The objective was to enhance the dissolution rate through formulation optimization using hydrophilic binders such as hydroxypropyl methylcellulose (HPMC K4M), sodium carboxymethyl cellulose, and polyvinylpyrrolidone K30 at varying concentrations. Ten formulations (F1-F10) were developed using wet granulation and evaluated for flow properties, compressibility, drug content, and in vitro dissolution. A 32 full factorial design was employed to assess the effects of binder type and concentration on key responses, including percentage drug release at 60 and 120 min, tablet hardness, and Carr’s Index. The optimized formulation (F3), containing 7.5% HPMC K4M, exhibited excellent flowability, acceptable hardness, and superior drug release over 70% at 60 min and nearly 99% at 120 min. Fourier-transform infrared spectroscopy analysis confirmed drug-excipient compatibility, and scanning electron microscopy studies revealed a transformation from crystalline to granular morphology. The optimized formulation also showed stability over 3 months under accelerated conditions with minimal changes in physicochemical parameters. Statistical modeling and analysis of variance confirmed the significant influence of both binder type and concentration on drug release and tablet properties. These findings support the use of hydrophilic binders in wet granulation to improve dissolution characteristics of felodipine.