A Study Of Preparation For Dextrin Nano Microsphere

Nano-microspheres as a new type of drug carrier was a hot research spot in nano-biotechnology. This drug carrier could be used in the targeting or localizing drug delivery area, particularly anti-cancer drugs. Dextrin is a widely used, easily degradable, and no contaminative agent. Dextrin microspheres could be served as drug carrier that could have the protective effect on a drug, and also have a control-released ability for the drug is adsorpted in the carrier. In this thesis, Dextrin nano-microspheres (DNMP) were prepared, and it’s characteristic was studied in its drug absorption and degradation.DNMP were prepared with inverse microemulsion using dextrin as the raw material, N-hexane as dispersed phase, Span60and Tween60as emulsifying agent, pentanol as assistant of surfactant, and Na3P3O9as linking agent. Factors affected preparing DNMP were chosen and an orthogonal experiment was conducted for optimizing these factors. DNMP were characterized by scanning electronic microscope, granularity analyzer, and Infra-red spectrum. Adsorption quantity of DNMP for methylene blue trihydrate was observed based on the factors affecting preparing DNMP. A buffer at pH7.4to simulate the blood condition of the human was chosen, and the adsorbing and releasing capability of DNMP for ceftriaxone sodium was examined.The adsorption quantity of DNMP for methylene blue trihydrate was decreased with the increase of the concentration of dextrin solution, volume ration between aqueous phase and dispersed phase, dosage of the linking agent, the reactive time, dosage of pentanol and pH. The adsorption quantity of DNMP was increased with the stir speed. The effect order of the seven factors on adsorption of DNMP was:volume ration between aqueous phase and dispersed phase> stir speed> concentration of dextrin solution> dosage of the linking agent> reactive time> dosage of pentanol> pH. The optimum condition for preparing DNMP was concentration of dextrin solution2%, volume ration between aqueous phase and dispersed phase0.35, dosage of the linking agent0.012g, reactive time3h, dosage of pentanol21mL, pH9.5, stir speed16000r/min. The infrared spectrum showed that there were crosslinking reactions between dextrin and the Na3P3O9within DNMP that shaped roundish. The average granularity was178.5nm.The equilibrium for drug adsorption was reached to after1h. The temperature was not found to affect the drug adsorption significantly, and23.94%of DNMP was degraded with a-amylase in6h.DNMP prepared in this thesis had a good adsorption property for drugs, and was found to be degraded in the analog human blood condition.