Self-assembled supramolecular gels of reverse poloxamers and cyclodextrins

Langmuir. 2012 Aug 28;28(34):12457-62. doi: 10.1021/la3024452. Epub 2012 Aug 16.


A series of supramolecular aggregates were prepared using a poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide) (PPO-PEO-PPO) block copolymer and β- or α-cyclodextrins (CD). The combination of β-CD and the copolymer yields inclusion complexes (IC) with polypseudorotaxane structures. These are formed by complexation of the PPO blocks with β-CD molecules producing a powder precipitate with a certain crystallinity degree that can be evaluated by X-ray diffraction (XRD). In contrast, when combining α-CD with the block copolymer, the observed effect is an increase in the viscosity of the mixtures yielding fluid gels. Two cooperative effects come into play: the complexation of PEO blocks with α-CD and the hydrophobic interactions between PPO blocks in aqueous media. These two combined interactions lead to the formation of a macromolecular network. The resulting fluid gels were characterized using different techniques such as differential scanning calorimetry (DSC), viscometry, and XRD measurements.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gels
  • Polyethylene Glycols / chemistry*
  • Propylene Glycols / chemistry*
  • Transition Temperature
  • alpha-Cyclodextrins / chemistry*
  • beta-Cyclodextrins / chemistry*


  • Gels
  • Propylene Glycols
  • alpha-Cyclodextrins
  • beta-Cyclodextrins
  • poly(propylene oxide)-block-poly(ethylene oxide)-block-poly(propylene oxide)
  • Polyethylene Glycols