ABSTRACT
A new blend of elastomers containing niclosamide, the most potent molluscicide against snail vectors of schistosomiasis, has been prepared and subjected to in vitro release measurements. The blend consists of 70% natural rubber [NR], and 30% styrene butadiene rubber [SBR] with and without certain additives such as a porosigen [ammonium sulfate] and surfactant [sodium lauryl sulfate SLS] in different concentrations. The results revealed that the biocide release obeys a diffusion controlled mechanism with a complex release pattern, in all samples tested. The presence of SBR in NR matrix has markedly increased the NES release rate, while ammonium sulfate or SLS did not increase the release rate in general. This study indicated that mixing selected elastomers is more useful than the use of additives for developing of compositions possessing a required release rate