Study On Preparation Of Nano-modified Plant Molluscicide And Its Molluscicidal Synergistic Properties

This paper is trying to make full use of the rich and characteristic local plants and Ag nanoparticles to prevent the schistosomiasis in Chizhou. Here, the combination of research on inorganic-organic nanocomposites and on prevention of schistosomiasis is presented for the first time. A new field of application of nanoscience and technology is explored. By using nanomaterials, the molluscidical effect of local plants is improved notably. This is a total new research, which both has high academic innovation value and distinctive local characteristics. It also has great social effects on promotion of people's living standard. The main work can be summarized as follows:1. Because of abundant natural resources and fluke disease, ginkgo acid in ginkgo episperm is used as molluscicide. It is demonstrated that ginkgo acid is an effective molluscicide, which proves that ginkgo episperm has great potential for preventing schistosomiasis, according to different concentration, time and environment experiments. The toxicity test of the fish shows that the ginkgo episperm has lower toxicity than niclosamide, therefore, it is environmentally friendly. The research on using Ginkgo as molluscicide has important significance.2. Biological template methods are used to prepare silver nanoparticles under mild conditions. XRD pattern, SEM image, IR and UV-Vis spectra, are used to characterize the structure and properties of the products. It is proved that the as prepared Ag nanoparticles are biocompatible and easy to form inorganic-organic nanocmposites. The Ag nanoparticles can greatly inhibit oncomelania, nearly 73.3-93.4% of oncomelania are killed by using Ag nanoparticles with the concentration range from 17.6mg/L to 88mg/L. In the toxicity examination for fish, the Ag nanoparticles exhibit rather low toxicity.3. Five kinds of molluscicides are prepared using the aforementioned materials: silver nanoparticles molluscicides, silver nanoparticles/ ginkgo episperm dry powder composites molluscicides, silver nanoparticles/ Ginkgo biloba exocarp ethanol soaking liquid composites molluscicides, Ginkgo biloba exocarp dry powder composites molluscicides, Ginkgo biloba exocarp ethanol soaking liquid composites molluscicides. Experiment results show that all the composites have molluscicidal effects, and the effects are improved greatly with time. Among them the silver nanoparticles/ ginkgo episperm dry powder composites molluscicides peform the best, in 36 hours the mortality of oncomelania is 86%, and in 84 hours the mortality reaches 100%. In the toxicity examination, the composites exhibit rather low toxicity.The study constructs a composite molluscicide system combining inorganic nanomaterials with organic biomaterials, and investigates its properties as molluscicides. The results present an efficient utilization value.