A Study of HPMC-PEG Matrix as Drug Carrier in Spray Congealing

Spray congealing offers a number of advantages in the development of specialised drug delivery systems. In this study, various grades of polyethylene glycol (PEG) and types of additives commonly used in formulating modified release dosage forms were screened for suitability as matrix material and matrix modifier for spray congealing. Screening of the additives showed that hydroxypropyl methylcellulose (HPMC) was an appropriate matrix modifier for PEG. The impact of grade and concentration of HPMC on the physicochemical properties of the molten mixtures, drug (metronidazole), PEG matrix and spray congealed microparticles was investigated. Among the physicochemical properties investigated were rheology of the molten mixtures, drug crystallinity, matrix swellability and erosion, as well as drug release rate and mechanisms. Rheological properties of the molten mixtures were evaluated using surface plots and principal component analysis. Suitable formulations were selected for the production of spray congealed microparticles, which were developed into tablets as the final dosage form.

Author dc:creator

• OH CHING MIEN

• spray congealing, hydroxypropyl methylcellulose, polyethylene glycol, viscosity, crystallinity, swellability