A. Dakkuri, H. Schroeder, P. Deluca
Mar 1, 1978
Citations
0
Influential Citations
50
Citations
Quality indicators
Journal
Journal of pharmaceutical sciences
Abstract
Abstract The influence of several surfactants on the in vitro release of tripelennamine hydrochloride from a wax matrix was investigated. The congealed mass, obtained by dispersing the drug and surfactant in a molten mixture of carnauba wax and stearyl alcohol, was granulated and compressed into cores. While controlling particle-size distribution, tablet hardness, and weight, dissolution in simulated intestinal fluid was measured with the rotating-basket method. Water-insoluble surfactants such as glyceryl monostearate had no effect on the dissolution rate; slightly soluble or slowly soluhle agents, such as sodium stearate, ammonium stearate, triethanolarnine, and dioctyl sodium sulfosuccinate moderately increased dissolution. However, the water-soluhle hydrophilic polyoxyethylene 23 lauryl ether considerably increased the dissolution rate; i.e. , about 80% of drug was released by a zero-order process over 4 hr. Since only a few surfactants were investigated, it is difficult to explain the difference in dissolution rate on the basis of ionic character. The profound effect of polyoxyethylene 23 lauryl ether could be attributed to both its hydrophilic nature and wetting action in an aqueous environment at the liquid-solid interface. Only with polyoxyethylene 23 lauryl ether was more than 50% released over 8 hr. With no surfactant present, approximately 38% was released, and release in the 1st hr was most rapid. The data suggest that a surfactant may make more channels available for the dissolution fluid to leach out the drug. Thus, the effective porosity of the matrix is increased. Furthermore, wetting is an important factor that controls matrix permeability.