چكيده لاتين :
The effect of different kinds of surfactants in various concentrations incorporated in an
inert matrix, on the release of procain amide hydrochloride, as a cationic model compound, was
investigated in this study. Sodium lauryl sulfate and sodium stearate as anionic surfactants,
cetyl pyridinium chloride and cetyltrimethyl ammonium bromide as cationic and span 60 and
tween 80 as non-ionic surfactants were selected. Hydrophobic matrices were prepared using
procainamide Hel, ethyl cellulose, dicalcium phosphate and different percentages of each
surfactant and the dissolution rate ofdrug from various matrices was determined in pH valuesl.2
(for 2 h) and 7.2 (up to 10 h). The results showed that incorporation of anionic surfactants
in matrix preparations resulted in a remarkable decrease in the release rate of procainamide
He] (P < 0.05), which was attributed to the formation of a poorly soluble complex between
the cationic drug and the anionic surfactant. The formation of complex was confirmed by the
precipitation titration test. On the other hand, presence of cationic surfactants considerably
increased the drug release rate and it was noted that by raising the percentage of surfactant, a
faster drug release rate release was achieved. With span 60 there was no change in drug release
rate, probably due to its lower wetting capability. While in the case oftween 80, as a hydrophilic
non-ionic surfactant, the drug release rate was increased, although statistically not significant.
In general, it seems that the influence of cationic and non-ionic surfactants on drug release rate
was in accordance with the ability of each surfactant in wetting the matrices and producing a
greater number of channels for the dissolution fluid to leach out the drug. Kinetics evaluation of
the release profiles showed that the Higuchi equation is the main model, fitting the data.
