Acta Chimica Sinica ›› 2012, Vol. 70 ›› Issue (19): 2016-2023.DOI: 10.6023/A12060270 Previous Articles     Next Articles



余旭东a,b, 刘倩a, 许秀芳c, 兰海闯a, 曹新华a, 陈黎明a, 刘斌a, 易涛a   

  1. a 复旦大学化学系 上海 200433;
    b 河北科技大学理学院 石家庄 050080;
    c 南开大学化学系 天津 300071
  • 投稿日期:2012-06-01 发布日期:2012-07-13
  • 通讯作者: 易涛
  • 基金资助:

    项目受国家自然科学基金(Nos. 91022021 and 30890141);973项目(No. 2009CB930400);教育部创新团队(No. IRT1117)和上海市重点学科(No. B108)资助.

Ultrasound Assisted Co-aggregation of a Two-component System with Multicolor Emission and Its Response to Acid

Yu Xudonga,b, Liu Qiana, Xu Xiufangc, Lan Haichuanga, Cao Xinhuaa, Chen Liminga, Liu Bina, Yi Taoa   

  1. a Department of Chemistry, Fudan University, Shanghai 200433;
    b College of Science, Hebei University of Science and Technology, Shijiazhuang 050080;
    c Department of Chemistry, Nankai University, Tianjin 300071
  • Received:2012-06-01 Published:2012-07-13
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 91022021 and 30890141), the National Basic Research Program of China (No. 2009CB930400), the Program for Innovative Research Team in University (No. IRT1117) and the Shanghai Leading Academic Discipline Project (No. B108).

In this paper, a two-component gel/micro-crystal system including amino acid and imidazole-based derivatives with blue and red emission, respectively, is designed and obtained. The two emission colors are convenient for the study of the co-aggregation of the two molecules via double channel confocal laser scanning microscopy. The two-component system could response to ultrasound with the morphology change from the mixture of club-shaped microcrystals and helical fibers by a thermal process to homogenous fibers exposing to sonication. Further evidence for the co-aggregation of the two components was obtained from circular dichromism (CD), IR spectra and X-ray powder diffraction. The self-assembly process between the two components was also studied by optimized molecular geometry calculation. Moreover, the co-aggregation obtained by the sonication then heating-cooling process, could not be destroyed by repeated heating-cooling. The gel-sol process could be further repeated for many times, suggesting that the co-aggregated gel was thermal-stable. It can be deduced that sonication weakened the intermolecular interaction between congeneric molecules and promoted the intermolecular hydrogen bonding between the two components. The results indicate that cooperation of the sonication and thermal processes is an effective way to prohibit phase separation and to promote gelation in the gel/micro-crystal system. Thus, a light harvest system is achieved by co-aggregation of the two components at nanoscale by means of sonication. The emission color of these two-component gels can be tuned by changing the ratio of the two compounds. These gels are sensitive to acid, givingclear spectral variation, accompanied by a gel to sol transition. The morphology of the two-component system is changed from a fiber structure to vesicles without phase separation when responding to acid and metal ions. Moreover, both the gel state and the morphology can be reversed by further addition of alkali. This kind of multifunctional and tunable two-component gel should have potential applications on the fields of visible molecular recognition, controllable release, stimulus responsive and memory materials.

Key words: two-component gel, ultrasound, co-aggregation, fluorescence, acid response