Pharmaceutical Technology: Controlled Drug Release, Volume 2

98 CH. 8] TOPICAL RELEASE AND PERMEATION STUDIES
Table 7—Computed parameters for Methocel® m atrix diffusion data through hairless mouse skin (up to 12 h)
Table 8—Permeability rate of propranolol hydrochloride from Methocel® matrix diffusion study through hairless
mouse skin (comparative data)
a Concentration represents average of three determinations.
b Statistical analysis performed by the F test and confidence interval (95%) methods: NS, statistically not significant; SS,
statistically significant.
coefficient value (3.0×10−7 cm2/s), compared with the emulsion base formulation with only 0.
11×10 −7 cm 2 /s. In addition, the highest permeability coefficient of 1.90×10 −7 cm 2 /s was obtained
for this formulation, compared with the emulsion-based sample with a value of 0.40×10−7 cm2/s.
However, the partition coefficient is observed to be the lowest for the Methocel ® matrix
formulation (0.38×10 −1 cm 2 /s) compared with the value of 2.30×10 −1 cm 2 /s obtained with the
emulsion base formulation, which gave the minimum release of the drug. For higher drug release
the formulation should possess relatively high permeability and diffusion coefficient.
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