In order to evaluate the pHs effect on the transdermal drug delivery, HPMC/PVA based TDS-patch was prepared. In vitro transdermal dissolution was performed at 32 ^oC at different pHs. Comparatively higher release rate was found in case of pH 7.4 than those of others. pHs 5.4 and 8 showed almost the same release pattern. The release fashion was Higuchi type of diffusion controlled release. This result showed that neutral pH would accumulate the maximum drug from such a TDS patch, where the skin pH (around 5.4) does not support such a release. Sustained release of drug from such a patch prefers skin pH rather than neutral pH.

Keywords : Transdermal drug delivery; Higuchi diffusion; Release rate; Metformin.

© 2011 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.

doi:10.3329/jsr.v3i3.7422 J. Sci. Res. 3 (3), 661-667 (2011)