Bioinspired Metal–Ligand Networks with Enhanced Stability and Performance: Facile Preparation of Hydroxypyridinone (HOPO)-Functionalized Materials

Bioinspired hydroxypyridinone (HOPO)­functionalized materials are shown to display a remarkable capacity for stability and for chelating a wide array of metal ions. This allows for the synthesis of multifunctional networks with diverse physical properties when compared to traditional catechol systems. In the present study, we report a facile, one-pot synthesis of an amino HOPO ligand and simple, scalable incorporation into PEG-acrylate based networks via active ester chemistry. This modular network approach allows for fabrication of patterned HOPO containing networks which can chelate a range of metal ions, such as transition metals (Fe3+) and lanthanides (Ho3+, Tb3+), leading to modulation of mechanical, magnetic, and fluorescent properties. Moreover, networks with tailored, heterogeneous properties can be prepared through localization of metal ion incorporation in 3-dimensions via masking techniques, creating distinctly soft, hard, magnetic, and fluorescent domains.