Journal
INTERNATIONAL JOURNAL OF PHARMACEUTICS
Volume 333, Issue 1-2, Pages 143-151Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.ijpharm.2006.11.067
Keywords
hydrophilic matrices; swelling study; release kinetics; controlled drug release
Categories
Ask authors/readers for more resources
The aim of the present study is an investigation of the swelling behaviour of matrix systems containing a mixture of hydroxypropylmethylcellulose (HPMC) and sodium carboxymethylcellulose (NaCMC) with a model soluble drug to find the correlation between the morphological behaviour and the drug release performance. The swelling study was conducted on tablets containing only the drug and the two polymers mixture (MB) and on reference tablets containing each polymer and the same drug, at three different pHs. NIB matrices show a similar swelling trend at pH 4.5 and 6.8, while they have different behaviour in acidic fluid. At pH I the gel layer formed by NaCMC is characterized by a rigid structure of a partially chemically crosslinked hydrogel while HPMC and MB matrices form a physical not crosslinked gel. At pH 4.5 and 6.8, all the systems show the typical morphological behaviour of a swellable matrix in which the macromolecular chains in the gel network are held together by weak bondings (physical gel). In these buffers, NIB systems maintain a constant drug release rate coupling diffusion and erosion mechanism: the gel and infiltrated layers thicknesses are maintained constant and a zero-order release kinetics can be achieved. (c) 2006 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available