While this review covered advances in design of metallopolymers with various sustainable applications, it also revealed gaps and challenges in research of metallopolymers such as their characterization and their use in fabrication of devices, establishing the need for more research to push the frontiers of this growing interdisciplinary area.

Ferrocene-containing polymers have been investigated for more than six decades, and more recently modern synthetic methods have allowed the fabrication of precise polymers that contain a variety of transition-metal complexes. Trends are now oriented towards applications, such as optics, energy conversion and storage, electrochemistry, magnetics, electric conductors and biomedicine. Metal-sandwich complexes such as those of ferrocene type and other related complexes that present redox-robust groups in polymers, i.e. that are isolable in both their oxidized and reduced forms, are of particular interest, because it is possible to address them using electronic or photonic redox stimuli for application. Our research groups have called such complexes Electron-Reservoirs and introduced them in the main chain or in the side chains of well-defined polymers. For instance, polymers with ferrocene in the main chain or in the side chain are oxidized to stable polycationic polyelectrolytes only if ferrocene is part of a biferrocene unit, because biferrocene oxidation leads to the biferrocenium cation that is stabilized by the mixed valency. Then a group of several redox-robust iron sandwich complexes were fabricated and incorporated in precise polymers including multi-block copolymers whose controlled synthesis and block incorporation was achieved for instance using ring-opening-metathesis polymerization. Applications of this family of Electron-Reservoir-containing polymers includes electrochemically induced derivatization of electrodes by decorating them with these polymers, molecular recognition and redox sensing, electrochromics with multiple colours, generation of gold and silver nanoparticles of various size by reduction of gold(III) and silver(I) precursors and their use for nanocatalysis towards depollution and biomedicine.

CD16a (FcγRIIIa) mediates the antibody dependent cellular cytotoxicity (ADCC) and is important for anti-tumor activities of many therapeutic antibodies. Bispecific antibody targeting natural killer (NK) cells has been studied for cancer therapy. In this work, anti-CD16a single-domain antibodies were identified from hCD16a immunized camel. Bispecific antibodies are then constructed by fusing these single domain antibodies with an anti-CEA single domain antibody. These bispecific antibodies can recruite NK cells to kill CEA-positive tumor cells, and inhibit tumor growth in vivo, suggesting that these anti-CD16a single domain antibodies are powerful tools to engaging NK cells for cancer therapy.