First-order release kinetics is characterized by a linear dependence of the release rate on the
released amount of the active ingredient, the triple of the absolute value of the exponent of the
exponential function expressing the reactive fractal dimension DR. Scopolamine bromide release
from hydroxypropylmethylcellulose hydrogel was first expressed by first-order kinetics with an
estimated DR ranging from 2.98–3.00. The employment of an exponential equation with the
exponent of release n renders it possible to make an assumption about the mechanism of release.
Within a range of n=0.505–0.550, estimated DR=2.46–2.94. In this region, release by means of the
mechanism of Fick’s diffusion prevails.DR=(3/n) – 3 generally holds true for the relationship between
both variables, which makes it possible to use the knowledge gained in the experimental influencing
of the exponent of release in the examination of the relationship between the reactive fractal
dimension and the mechanism of release of scopolamine bromide from hydrogel. An increase in the
exponent of release markedly decreases the corresponding values of reactive fractal dimension.
reactive fractal dimension – release kinetics – scopolamine bromide – hydrogel