The effect of chemical heterogeneity of HPMC on polymer release from matrix tablets
Journal article, 2009

Polymer release from hydrophilic matrix tablets, composed of hydroxypropyl methylcellulose, was studied for seven different polymer batches. A time difference of more than 80h between fully dissolved tablets was noticed although the batches were of the same pharmaceutical substituent (USP 2208) and viscosity (100 cps) grade. To find the functionality related parameters for polymer release from hydrophilic matrix tablets the polymer samples were characterised according to size and chemical composition. The size of the polymers was characterised by size-exclusion chromatography with multi-angle light scattering and refractive index detection. The average amount of substituents was measured with nuclear magnetic resonance and the distribution of the substituents along the cellulose chain was determined with high-performance anion-exchange chromatography with pulsed amperometric detection after acid and enzymatic hydrolysis. The results indicated that other types of interactions apart from entanglements were present between the polymer chains, which seemed to affect the polymer release. Most importantly, this study has shown a correlation between the polymer release and the substituent pattern, where the samples with slow release also were more heterogeneously substituted along the polymer chain. From this we can conclude that polymer release is very sensitive to alterations in chemical composition.

Magnetic Resonance Spectroscopy

Chromatography

*Polymers: CH

chemistry

chemistry

*Tablets

analogs & derivatives

Gel

Molecular Weight

*Methylcellulose: AA

Methylcellulose: CH

0 (Tablets)

0 (Polymers)

Author

Anna Viridén

SuMo Biomaterials

Chalmers, Chemical and Biological Engineering, Pharmaceutical Technology

Bengt Wittgren

AstraZeneca AB

Thomas Andersson

AstraZeneca AB

Anette Larsson

SuMo Biomaterials

Chalmers, Chemical and Biological Engineering, Pharmaceutical Technology

European journal of pharmaceutical sciences official journal of the European Federation for Pharmaceutical Sciences

1879-0720 (ISSN)

Vol. 36 4-5 392-400

Subject Categories

Pharmaceutical Sciences

DOI

10.1016/j.ejps.2008.11.003

PubMed

19049865

More information

Latest update

8/18/2020