化学学报 ›› 2016, Vol. 74 ›› Issue (4): 369-374.DOI: 10.6023/A15120755 上一篇    

研究论文

2-羟基-3-异丙氧基丙基羟乙基纤维素的合成及其自组装行为的研究

田野, 具本植, 张淑芬   

  1. 大连理工大学 精细化工国家重点实验室 大连 116024
  • 收稿日期:2015-12-03 出版日期:2016-04-15 发布日期:2016-02-23
  • 通讯作者: 具本植 E-mail:jubenzhi@dlut.edu.cn
  • 基金资助:

    项目受国家自然科学基金委创新团队(No. 21421005)、国家自然科学基金(No. 21376041)和教育部创新团队(IRT-13R06)资助.

Synthesis and Self-Assembly Behavior of Temperature Responsive 2-Hydroxy-3-Isopropoxypropyl Hydroxyethyl Cellulose

Tian Ye, Ju Benzhi, Zhang Shufen   

  1. State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024
  • Received:2015-12-03 Online:2016-04-15 Published:2016-02-23
  • Supported by:

    Project supported by innovative research groups of the National Natural Science Fund Committee of Science (No. 21421005), the National Natural Science Foundation of China (No. 21376041), and Innovation team of Ministry of Education (IRT-13R06).

通过醚化反应, 将疏水性试剂异丙基缩水甘油醚(IPGE), 接枝到以羟乙基纤维素为亲水性骨架的主链上, 合成了具有温度响应性的2-羟基-3-异丙氧基丙基羟乙基纤维素(HIPEC), 运用核磁共振(1H NMR、13C NMR、2D HSQC NMR)对HIPEC进行结构表征, 其最低临界溶解温度(LCST)可通过改变疏水侧链的摩尔取代度(MS)和盐浓度来调节. 通过荧光光谱仪、动态光散射(DLS)、共聚焦荧光显微镜(CLSM)研究了HIPEC在水溶液中自组装行为及Nile Red在HIPEC胶束中的增溶行为和温度控制释放行为, 结果表明, HIPEC在溶液中自组装形成胶束, 并且胶束粒径随着温度的升高而增大; 在温度高于LCST时, Nile Red从HIPEC胶束中缓慢释放, 并且可通过改变温度控制Nile Red的释放过程.

关键词: 纤维素醚, 温度响应性, LCST, 自组装, 可控释放

Responsive polymers have attracted great interests in many application fields. Thermoresponsive polymers are especially appealing, and have been applied in biomedical and biotechnological fields. A thermoresponsive polymer, 2-hydroxy-3-isopropoxypropyl hydroxyethyl cellulose (HIPEC), was prepared by etherification reaction, which grafted isopropyl glycidyl ether (IPGE) onto hydroxyethyl cellulose (HEC). The HIPEC was characterized by 1H NMR, 13C NMR, and 2D HSQC NMR, and the molar substitution (MS) of HIPEC was determined by 1H NMR. The lower critical solution temperature (LCST) of HIPEC can be tuned from 17.0~43.0 ℃ by changing MS of hydrophobic groups from 1.21~2.88. The salt concentration has a significant influence on LCST, the experiment results indicated that the LCST of HIPEC decreased with increasing NaCl concentration. Amphiphilic, thermoresponsive polymers can form micelles in aqueous solution and encapsulate guest molecules. Fluorescence spectroscopy and dynamic light scattering (DLS) showed that HIPEC can assemble into micelles, and micelles diameter significantly increase with increasing temperature. It is indicated that the morphologies of the HIPEC micelles can be varied by changing temperature. The critical micelle concentrations (CMC) of HIPEC which were measured by fluorescence spectroscopy decreased with increasing of the MS of hydrophobic groups. Additionally, using Nile Red as a probe, fluorescence spectroscopy and confocal laser scan microscope (CLSM) were applied to the HIPEC aqueous solution to examine the encapsulation of Nile Red aqueous solutions of the HIPEC. The research results show that Nile Red can be encapsulated and stabilized in the hydrophobic core of HIPEC micelles. The fluorescence intensity of Nile Red increased with increasing of HIPEC concentration, and there is a sharp increase in the number of HIPEC micelles above CMC. Because the morphologies of HIPEC micelles were disrupted when the temperature reached the LCST, the Nile Red which was capsulated in HIPEC micelles can be slowly released from HIPEC micelles over a much longer period of time, and the release process can be controlled by changing temperature.

Key words: cellulose ether, thermoresponsivity, LCST, self assembly, controlled release