Dendrimer for Templating the Growth of Porous Catechol-Coordinated Titanium Dioxide Frameworks: Toward Hemocompatible Nanomaterials

Phosphorus dendrimers and nanosized metal oxide clusters are two dissimilar nanomaterials with promising applications in nanomedicine. Although outstanding holistic properties can be reached by the combination of organic and inorganic phases, few investigations were strikingly undertaken to associate these building blocks in a single nanostructured, open-framework hybrid material. With this aim, we designed herein five novel different generations of catechol-terminated phosphorus dendrimers (DGn: n = 1–5) and used them as structure-directing agents for titanium alkoxide mineralization. The covalent bonding occurring between peripheral catechols and soluble titanium oxo species and their further sol–gel cocondensation afford bimodal micromesoporous catechol-coordinated titanium dioxide nanomaterials. Their interplay with cells was assessed with a special emphasis on their hemolytic activity and cytotoxicity. Interestingly, enhanced biocompatibility was observed for these materials compared to their hybrid analogues built from ammonium- and phosphonate-terminated phosphorus dendrimers. These results demonstrate the importance of catechol-terminated groups both for bridging titanium dioxide clusters and for improving the materials’ compatibility. Overall, this study sheds light on the importance of tuning the surface-interface hybrid composition and provides a blueprint for the rational design of blood-compatible and drug-transporter materials.