Gradient Enhancement of Supramolecular Organic Framework for Solubilization of Hydrophobic Molecules by Two Molecular Containers in Water

Many functional organic molecules have very low water-solubility, which remarkably limits their practical applications. The inclusion of water-soluble hosts has been demonstrated as an important strategy to increase the water solubility of organic molecules. However, this strategy usually requires high concentration for the hosts to realize efficient solubilization of guest molecules. Herein a new strategy of gradient solubilization by utilizing a water-soluble porous supramolecular polymer to adsorb or enrich molecular containers to increase their efficient concentration in a confined space is reported. For this aim, a cationic water-soluble supramolecular organic framework was used to include an anionic calix[5]arene or an anionic acyclic cucurbituril. In this way, the supramolecular organic framework was revealed to exhibit significant gradient enhancement for the solubilization of the calix[5]arene host for C-60, C-70, ferrocene, 1,1'-dimethylferrocene and 1,1'-dibromoferrocene, and the solubilization of the acyclic cucurbituril host for paclitaxel, docetaxel and cabazitaxel.

Automated summary

Functional organic molecules often have low water solubility, limiting their practical applications. Utilizing a water-soluble porous supramolecular polymer for gradient solubilization can increase the solubility of organic molecules and enhance their concentration in a confined space.