The effect of hydrogen-bonds of amino acid-derived diacetylene by photopolymerization in supramolecular hydrogels

J Nanosci Nanotechnol. 2011 Mar;11(3):2113-20. doi: 10.1166/jnn.2011.3141.

Abstract

Amino acids derived diacetylene hydrogelators 1 and 2 which have glycine or alanine moiety as head group were synthesized by several steps. The influences on the hydrogen-bonding interaction between amino acids moieties of hydrogelators in the polymerization by UV irradiation were investigated. The glycine-based hydrogel 1 resulted in the generation of stronger absorption peak at 540 nm at room temperature by UV-irradiation. Interestingly, the red color of the glycine-based diacetylene hydrogel 1 was gradually changed into blue color by decreasing temperature. Finally, the absorption band with 640 nm of glycine-based diacetylene hydrogel 1 showed at 77 K. On the other hand, the alanine-based hydrogel 2 had no significant color change at 77 K. These different color changes between the hydrogels 1 and 2 are attributed to the strong intermolecular hydrogen-bonding interaction between glycine moieties of the hydrogelator 1, as confirmed by FTIR observation. These results indicate that the hydrogen-bonding strength of the self-assembled hydrogel is a strong influence on the degree of polymerization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkynes / chemistry*
  • Alkynes / radiation effects
  • Amino Acids / chemistry*
  • Crystallization / methods*
  • Hydrogels / chemical synthesis*
  • Hydrogels / radiation effects
  • Hydrogen Bonding
  • Macromolecular Substances / chemistry
  • Macromolecular Substances / radiation effects
  • Materials Testing
  • Molecular Conformation / radiation effects
  • Nanostructures / chemistry*
  • Nanostructures / radiation effects
  • Nanostructures / ultrastructure
  • Particle Size
  • Polymers / chemical synthesis
  • Polymers / radiation effects
  • Surface Properties / radiation effects
  • Ultraviolet Rays

Substances

  • Alkynes
  • Amino Acids
  • Hydrogels
  • Macromolecular Substances
  • Polymers