Effect of Cross-Linking Properties on the Vibrational Dynamics of Cyclodextrins- Based Polymers: An Experimental-Numerical Study

The vibrational dynamics of cyclodextrin nanosponges (CDNS), a new class of nanostructured soft materials synthesized via cross-linking reaction of natural cyclic oligosaccharide β-cyclodextrin (β- CD) with suitable organic reagents, is investigated by means of the combined use of Raman and infrared spectroscopy, supported by numerical simulations. The vibrational spectra of the polymers show significant changes in the frequency ranges 3000−3700 and 1500−1800 cm−1 correlated to the relative amount of cross-linker with respect to monomeric CD. By using band deconvolution and best-fit procedure of the experimental data and quantum chemical computations, a correlation between such changes and the degree of cross-linking of the polymeric network is proposed. This experimental−numerical approach, here applied to a model class of nanoporous polymeric systems, appears to be of general application for the study of polymeric matrixes of interest for biolife applications.