Study On The New Formulations Of Niclosamide

Schistosomiasis japonica is a major infectious disease that severely threatens the health of the Chinese people, one of the four infectious diseases that the Chinese government is trying to control over during the period of the 11^th five-year planning. As Oncomelania snail is the only intermediate host, extirpation of the snail makes it possible to intercept the transmission of Schistosomiasis. Application of chemical molluscicides is one of the most effective measures for killing snail. Because it has the advantages of high efficiency and low toxicity, causing comparatively little environmental pollution, niclosamide is now the only chemical molluscicide allowed for use in China as well as the only molluscicide recommended by WHO for killing Oncomelania snails. However, niclosamide is poorly soluble either aqueous media and organic solvents, and therefore, its application is limited in field. To ensure its practical application, niclosamide ethanolamine salt (Bayluscide), which is of somewhat better solubility, was invented to increase its dissolution. Nevertheless it still fails to satisfactorily meet the demand for field application. Later Bayluscide was processed into a wettable powder to acquire a still better solubility. Thus it becomes applicable in practice. Yet it still has the evident disadvantages, for instance, requiring stirring to get it dispersed before application. In storage, it easily agglomerates with a declined suspension rate. As a result, it distributes unevenly with its molluscicidal efficiency decreased.Over the more than 40 years since its discovery as a molluscicide, how to increase the solubility of niclosamide to meet the requirement for practical applicability to play a bigger role in snail controlling has remained a challenge in the scientific research of prevention and treatment of schistosomiasis. To contribute to the prevention and treatment of schistosomiasis and serve the missions stipulated in the 11^th five-year program, this study is concerned with the improvement on the formulation of niclosamide, aiming at developing new formulations, the...