The Effect of Various Surfactants on Release Behavior of Procainamide Hel from Ethylcellulose Based Matrices

The effect of different kinds of surfactants in various concentrations incorporated in aninert matrix, on the release of procain amide hydrochloride, as a cationic model compound, wasinvestigated in this study. sodium lauryl sulfate and sodium stearate as anionic surfactants,cetyl pyridinium chloride and cetyltrimethyl ammonium bromide as cationic and span 60 andtween 80 as non-ionic surfactants were selected. hydrophobic matrices were prepared usingprocainamide hel, ethyl cellulose, dicalcium phosphate and different percentages of eachsurfactant 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 surfactantsin matrix preparations resulted in a remarkable decrease in the release rate of procainamidehe] (p < 0.05), which was attributed to the formation of a poorly soluble complex betweenthe cationic drug and the anionic surfactant. the formation of complex was confirmed by theprecipitation titration test. on the other hand, presence of cationic surfactants considerablyincreased the drug release rate and it was noted that by raising the percentage of surfactant, afaster drug release rate release was achieved. with span 60 there was no change in drug releaserate, probably due to its lower wetting capability. while in the case oftween 80, as a hydrophilicnon-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 ratewas in accordance with the ability of each surfactant in wetting the matrices and producing agreater number of channels for the dissolution fluid to leach out the drug. kinetics evaluation ofthe release profiles showed that the higuchi equation is the main model, fitting the data.