Molecularly Selective Regulation of Delivery Fluxes by Employing Supramolecular Interactions in Layer-by-Layer Films.

The molecularly selective regulation of molecular fluxes in a biomaterial that delivers multiple chemical species simultaneously is still beyond the reach of materials scientists. A delivery material was developed by means of the layer-by-layer (LbL) technique. This material discriminatively regulates the delivery flux of bioactive small molecules, as represented by a peptide containing the RGD fragment and the chemotherapy drug doxorubicin (DOX). Molecularly selective flux regulations in LbL films are realized through fast, reversible supramolecular interactions between cyclodextrin and its guests. The mechanism underlining the delivery strategy is that supramolecular interactions promote molecular loading and slow down diffusion-dependent release. In a preliminary survey of materials parameters, a maximum difference in cell viability between healthy human bronchial epithelial cells and cancer cells (A549) was realized.