Acta Chimica Sinica ›› 2007, Vol. 65 ›› Issue (21): 2459-2465. Previous Articles     Next Articles


曾蓉1,2,冯志程1,SMITH, Ray 2邵正中1,陈新*,1,杨宇红*,3   

  1. (1教育部聚合物分子工程重点实验室 复旦大学高分子科学系 上海 200433)
    (2伦敦大学玛丽女王学院材料系 伦敦 E1 4NS 英国)
    (3复旦大学分析测试中心 上海 200433)
  • 投稿日期:2007-01-24 修回日期:2007-03-26 发布日期:2007-11-14
  • 通讯作者: 陈新, 杨宇红

Exploring Study of Chitosan/Glycerophosphate Thermosensitive Hy-drogel with Variable-temperature NMR

ZENG Rong1,2; FENG Zhi-Cheng1; SMITH Ray2; SHAO Zheng-Zhong1; CHEN Xin*,1; YANG Yu-Hong*,3   

  1. (1 The Key Laboratory of Molecular Engineering of Polymers of the Ministry of Education of China, Department of Macromolecular Science, Fudan University, Shanghai 200433, China)
    (2 Department of Materials, College of Queen Mary, University of Lon-don, London E1 4NS, UK)
    (3 The Research Center of Analysis and Measure-ment, Fudan University, Shanghai 200433, China)
  • Received:2007-01-24 Revised:2007-03-26 Published:2007-11-14
  • Contact: CHEN Xin; YANG Yu-Hong

Variable-temperature NMR techniques were applied to monitor the gelation process of chitosan/glycerophosphate (CS/GP) thermosensitive hydrogel system. The results showed that the chemical shifts of protons in CS and phosphor in GP changed together while the temperature was increased. However, the protons in CS shown in 1H NMR spectra moved to the high field, but the phosphor shown in 13P NMR moved to the low field. In addition, the chemical shift of H-2(D) in CS showed a turning point around the gelation temperature, indicating that the chemical environment of H-2(D) has been changed dramatically. Moreover, the chemical shift of H-2(D) in CS moved to higher field and the CS/GP system showed the lower gelation temperature with the increase of either GP content or pH value of the CS/GP mixture. Therefore, the gelation mechanism of CS/GP thermosensitive hydrogel was deduced as follows: with the increase of temperature, the electrostatic interaction between CS and GP is broken down, followed by the formation of hydrogen bonds between CS macromolecular chains, which induce the gelation.

Key words: smart hydrogel, chemical shift, 1H NMR, 13P NMR, hydrogen bonding, electrostatic interaction