Summary: | 碩士 === 國立成功大學 === 材料科學及工程學系碩博士班 === 94 === In this study, chitosan(CTS) and chondroitin sulfate(ChS), two poly-electrolytes, were used to form nanoparticles through electrostatic force by a step dropwise method. These particles were evaluated their application for drug delivery of 5-fluorouacail(5-FU). According to FTIR analysis, there exists the bonding of NH3+ of CTS together with COO- and OSO3- of ChS in the complexes. It demonstrates that the complexes are formed by electrostatic force of these two poly-electrolytes. Then, it is observed the influence of the concentration ratio of CTS/ChS, reaction pH value and the viscosity molecular weight(Mv) of CTS on the particle size and zeta potential of CTS-ChS particles. It is found that the CTS-ChS particles with average size of 145 nm could be obtained with the concentration ratio of CTS and ChS of 4:3, reacted in pH 3 condition and the Mv of CTS being 80 kDa.
The in-vitro release profiles of the 5-FU are established in phosphate buffer solution (PBS) pH=7.4 at 37℃. Encapsulation efficiency (EE) of drug for different mixing procedure of 5-FU/CTS with ChS or 5-FU/ChS with CTS is compared, the later shows a higher EE up to 42.5±1.1%. The influence of the amount of initial drug on the EE is shown that the highest EE up to 70.4±2.1% could be obtained for the addition of 10 mg. In addition, as the pH value or Mv of CTS increases, the EE of 5-FU would increase. The result of drug release shows that whether the Mv of CTS is 600 kDa, 200 kDa or 80 kDa, 5-FU/CTS-ChS particles follow two steps Higuchi model for the drug release kinetics. Besides, the release rate and release amount of 5-FU increase for the lower Mv of CTS.
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