Correlation between the FT-IR characteristics and metoprolol tartrate release of methylcellulose-based patches.

The aim of the present study was to investigate how the drug release and FT-IR characteristics of metolose patches were influenced by the changes of Metolose SM 4000 (methylcellulose) and Metolose 90SH 100.000SR (hypromellose) proportions. FT-IR spectroscopy measurements were performed in parallel with the metoprolol tartrate release study to track the effect of the composition on the drug release.

Correlation between the free volume and the metoprolol tartrate release of Metolose patches.

The correlation between the release characteristics of metoprolol tartrate and the free volumes of Metolose patches containing Metolose 90SH 100.000SR (hypromellose) and Metolose SM 4000 (methylcellulose) of various proportions was studied. Positron annihilation lifetime spectroscopy (PALS) measurements were performed in parallel with the metoprolol tartrate release study to track the free volume changes of patches.

The influence of Metolose structure on the free volume and the consequent metoprolol tartrate release of patches.

Matrix-type patches containing Metoprolol tartrate were prepared from two types of Metolose and acrylate polymers. Metolose SM 4000 and Metolose 90SH 100.000SR were applied in different proportions in the patches where the total polymer content was kept constant in each sample.