The Synthesis And Characterization Of The Biodegradable Drug-graft-polyester Elastomer

In this paper,5-fluorouracil-1-acetic acid was synthesized from 5-fluorouracil (5-Fu) by adding chloroacetic acid under alkaline condition and characterized by IR and NMR. By melt polycondensation method, poly(glycerol-sebacate-(5-fluorouracil-1-acetic acid)) ester series were synthesized on different concentrations of 5-fluorouracil-1-acetic and different ratio of sebacic acid and glycerol; poly(glycerol-sebacate-curcumin) ester series doped with different concentrations of curcumin were also synthesized in the certain proportion of sebacic acid and glycerol. The microstructure, mechanical properties, and drug release behaviors of esters were characterized by Infrared Spectroscopy, IR, Nuclear Magnetic Resonance,X-ray diffraction, scanning electron microscopy, tensile, and high efficiency liquid chromatography (HPLC).The carboxylic acid group of 5-fluorouracil-1-acetic acid could be detected by NMR. By biological effects testing,5-fluorouracil-1-acetic acid showed significant inhibition for tumor cells. Poly(glycerol-sebacate-(5-fluorouracil-1-acetic acid)) ester could be synthesized from 5-fluorouracil-1-acetic acid successfully. With the increase of concentration of 5-fluorouracil-1-acetic, the internal hydrogen bonding of polymer elastomer became weakened, hydrophilic and elastic modulus of polymer elastomer decreased, crosslinking density of polymer elastomer decreased and then increased, the degradation rate of polymer elastomer increased. At the early stage, the drug release of the esters was fast, then, the drug release gradually became slow, and after 6 days, the drug release rate remained almost constant. With the reactant concentration of 5-fluorouracil-1-acetic acid increase, the drug release rate increased at the same release time.At the same reactant concentration of 5-fluorouracil-1-acetic acid, relative to the reactant molar 1.2:1 ratio of sebacic acid and glycerol,the samples on the reactant molar 1.5:1 ratio have higher crosslinking density, bigger elastic modulus, less weight loss during degradation, and lower drug release rate.Poly(glycerol-sebacate-curcumin) esters could be synthesized successfully.With the concentration of curcumin increase,the internal hydrogen bonding of esters increased, crosslinking densities of esters decreased, hydrophilic and elastic modulus of esters decreased. The poly(glycerol-sebacate-curcumin) esters had a linear weight loss during degradation, and at the 40% concentration of reactant curcumin, the mass loss was fastest. At the early stage, the drug release of the esters was fast, then, the drug release gradually became slow, and after 4 days, the drug release rate remained almost constant. With the concentration of reactant curcumin increasing, the curcumin release rates tended to increase.