摘要
以聚甲基乙烯基醚(PVME)和羧甲基壳聚糖(CMCS)为原料,采用电子束辐照交联方法制备聚甲基乙烯基醚/羧甲基壳聚糖(PVME/CMCS)水凝胶,研究了温度、pH值、CMCS含量等对PVME/CMCS水凝胶溶胀度的影响,同时以5-氟尿嘧啶(5-Fu)作模型药物,初步探讨了凝胶药物释放性能.结果表明,辐射剂量在20~40kGy时,凝胶分数随辐射剂量的增加而快速增加,辐射40kGy以后趋于平衡.在相同辐射剂量下,随着体系中CMCS含量的增加,凝胶分数反而减少.该水凝胶具有一定的温度和pH敏感性,其低临界溶解温度(LCST)在35℃左右,并且在相同时间内和25及37℃下的溶胀反复可逆,表现出较快的响应性.pH〈3.0和pH〉5.0时,溶胀度较大;pH值为3.0~5.0时,凝胶网络由于静电力收缩,溶胀度较小.CMCS含量的增加和辐射剂量的减小均可提高凝胶载药量.药物释放时间可通过改变体系中CMCS的含量和辐射剂量来调节.
Hydrogels based on poly( vinyl methyl ether) (PVME) and carboxymethylchitosan (CMCS) were prepared with electron beam irradiation(EB) cross-linking at room temperature. The effects of temperature, pH, CMCS content on the swelling properties of PVME/CMCS hydrogels were studied. The release behavior of a drug was tentatively investigated as well. The results show that the gel fraction of PVME/CMCS blend gels increases rapidly and then levels off above the radiation dose of 40 kGy, and it decreases with the increase of CMCS content in PVME/CMCS system. The hydrogels are thermo- and pH-sensitive, and show a fast swelling reversibility. At pH 〈 3.0 and pH 〉 5.0, the hydrogels have a higher swelling ratio ; however, the swelling ratio is relatively lower in the pH range of 3.0-5.0 due to the electrostatic force. Increasing CMCS content and decreasing irradiation dose can improve the drug loading. The release of 5-fluorouracil can be governed by regulating the CMCS content and irradiation dose.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第2期409-414,共6页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:50473061)
上海市科委基础研究重点项目(批准号:05JC14067)资助