Biomass Carbon Materials For Adsorption And Releasing Of Cercaricidal Drug

Schistosomiasis cerariae is the only period for the human infection,also is the most vulnerable period in the life cycle.The existing cercaricidal drugs have some drawbacks such as the short time of drug effect,so we need to prepare the long-acting and sustained-release drug.Biomass is one kinds of solid waste which derive from a wealth of sources.The biomass material has porous structure after pyrolysis which could be an excellent platform to loading drug.In this thesis,we select the biomass such as bamboo powder to be the precursor of carbon material.The precursors were pyrolyzed to obtained porous carbon materials.Then we used the biomass carbon materials to research the adsorption and releasing of cercaricidal drugs.1.Synthesis and characterization of biomass carbon materialsThe bamboo,sawdust(include poplar,locust tree and candlenut)and duckweed were selected to be biomass materials.The functional groups,surface morphology and specific surface area of the carbonized materials were characterized to investigate the influence of temperature and heating rate to carbonized materials.The results showed that the charring yields of the biomass were decreased with the increase of carbonized temperature.All the five kinds of biomass chars contain hydroxyl,aromatic and ether bond.The nitrogen adsorption data showed that the porous carbon materials possess micro and mesoporous structure.Compared with the specific surface area,the bamboo power which was pyrolyzed under 600 oC with the heating rate was 5 oC/min have the largest specific surface.2.The adsorption and drug delivery of cercaricidal drugIn order to study the adsorption and releasing process of polyether benzamide used of biomass char,the initial drug concentration and temperature were investigated.The experimental results showed that the adsorbing capacity of bamboo carbon materials increased with increasing of drug’s initial concentration,and the adsorption process reached equilibrium in five hours.Through the simulation of adsorption kinetics,the pseudo-second-order kinetic model provided a better correlation for the experimental data,and Freundlich model was more suitable to describe this adsorption process than Langmuir model.Moreover,the releasing time of cercaricidal drug loaded bamboo char which have high specific surface area can release up to several days.3.Floating properties and modification of biomass carbon materialsAim to the floating characteristic of Schistosomiasis cerariae,it needs the biomass carbon materials could float on the water.Paraffin wax was introduced to modify the porous carbon materials to increase their hydrophobic and prolong the floating time.Experimental results showed that the paraffin wax can play a role to improve the water contact angle of the materials thus extend the floating time of porous carbon materials.All the biomass carbon materials can float on the water up to sixty days through immersing in the concentration of 0.001mg·mL-1 wax solution for six hours.