Recognition-induced supramolecular porous nanosphere formation from cyclodextrin conjugated by cholic acid

A supramolecular porous nanosphere is constructed from amphiphilic cholic acid-modified cyclodextrin triggered by guest sodium 1-naphthylamino-4-sulfonate and is comprehensively characterized by nuclear magnetic resonance (NMR), light scattering, transmission electron microscopy, and gas adsorption experiments. The results obtained show that the porous nanosphere with the radius of 25-35 nm has moderate nitrogen adsorption ability. Further NMR, circular dichroism, and the fluorimetric titrations on the self-assembling behavior in aqueous solution reveal that the substituting group of the guest molecule and pH values are the key to induce the formation of the porous nanosphere.