Investigation of hypromellose particle size effects on drug release from sustained release hydrophilic matrix tablets.

Selected combinations of six model drugs and four hypromellose (USP 2208) viscosity grades were studied utilizing direct compression and in vitro dissolution testing. Experimental HPMC samples with differing particle size distributions (coarse, fine, narrow, bimodal) were generated by sieving. For some formulations, the impact of HPMC particle size changes was characterized by faster drug release and an apparent shift in drug release mechanism when less than 50% of the HPMC passed through a 230 mesh (63 microm) screen.

A framework to investigate drug release variability arising from hypromellose viscosity specifications in controlled release matrix tablets.

Substitution level, particle size, and molecular weight are key properties of hypromellose (HPMC) known to be important to its performance in pharmaceutical-controlled release applications. The hypromellose monographs indirectly specify acceptable ranges for the molecular weight of HPMC products, expressed as the apparent viscosity of a 2% aqueous solution. The purpose of this study was to provide a framework to systematically investigate the amount of drug release variability that might be expected for typical controlled release formulations over the monograph viscosity ranges for hypromellose.

A compaction process to enhance dissolution of poorly water-soluble drugs using hydroxypropyl methylcellulose.

The purpose of this study was to develop a technique to enhance the dissolution rate of poorly water-soluble drugs with hydroxypropyl methylcellulose (HPMC) without the use of solvent or heat addition. Three poorly water-soluble drugs, naproxen, nifedipine, and carbamazepine, were studied with low-viscosity HPMC USP Type 2208 (K3LV), HPMC USP Type 2910 (E3LV and E5LV), and methylcellulose. Polymer and drug were dry-blended, compressed into slugs on a tablet press or into ribbons on a roller compactor, and then milled into a granular powder.

Investigation of the effect of tablet surface area/volume on drug release from hydroxypropylmethylcellulose controlled-release matrix tablets.

The purpose of this study was to investigate the influence of tablet surface area/volume (SA/Vol) on drug release from controlled-release matrix tablets containing hydroxypropylmethylcellulose (HPMC). Soluble drugs (promethazine HCl, diphenhydramine HCl, and propranolol HCl) were utilized in this study to give predominantly diffusion-controlled release. Drug release from HPMC matrix tablets with similar values of SA/Vol was comparable within the same tablet shape (i.