Magnetic Drug-loaded Chitosan Microspheres And Its Characterization

In this paper, Fe3O4 magnetic particles were synthesized by chemical co-precipitation. Sodium oleate and PEG-4000 were used as bilayer surfactants to envelope the ultra-fine Fe3O4 particles to obtain the stabilized water base ferrofluid. Then methods such Laser Diffraction Particle Size Analyzer, SEM, XRD, IR, chemical analysis and Magnetic-Conductivity Measurement and so on were used to characterize it. Experiments indicated that surfactants and pH value of the solution when Fe3O4 particles were synthesized and enveloped had great effect on the stability and size of the magnetic fluid. Other effects of the preparation conditions were also studied.The chitosan mircospheres and 5-Fluorouacil loaded magnetic chitosan mircospheres were prepared with the "Suspension crosslinking technique" in ethyl benzoate, which was used as suspension medium. The preparation conditions such as the stirring speed, oil/solution ratio, amount of emulsifier, temperature, amount of crosslinker, deacetylated degree of chitosan and so on were deeply discussed. On the other hand, 5-Fluorouacil loaded magnetic chitosan mircospheres were studied primarily, including the preparation conditions, drug-loaded rate, particle size and the efficiency of drug release. Tests showed that the drug-loaded mircospheres had good spherical shape but low drug-loaded rate. 62.5% of the 5-Fluorouacil was released in the first two hours in the drug release test, after that the releasing speed of which slow down.