This project targets the synthesis of lanthanide(III) complexes with redox-sensitive ligands for monitoring of the redox status. A major downstream application is the non-invasive preclinical and biomedical imaging. We hypothesize that a change in the redox state of the ligand will influence both the lanthanide-based luminescence and the relaxation times (coordinated water molecules) for magnetic resonance imaging (MRI). Thus, the ligand will be the probe of the redox-status and the lanthanide will be the reporter. Polydentate ligands appended by pro-phenoxyl, pro-iminosemiquinonate and nitronyl nitroxide units will be prepared and chelated to a series of lanthanide ions: TbIII, EuIII for luminescence detection in the visible region, NdIII and YbIII for a luminescence in the NIR region and GdIII for application as contrast agents. The stability constants of the complexes will be determined and structural characterizations will be conducted. With the aim of improving the solubility and targeting the ligands will be appended by cell penetrating peptides or integrin recognition peptides. The operating potentials of the probes will be next investigated by electrochemical techniques (cyclic voltammetry, electrolysis). The complexes under their different redox states (radical or not) will be prepared both electrochemically and in vitro with biologically relevant reactants, and characterized by luminescence and relaxometric techniques. Having established that the oxidation state of the complexes could be monitored by luminescence and relaxivity, biological studies will be undertaken. They include MTT assays in order to ensure that the probes are non-toxic. Further in cellulo luminescence measurements (2D/3Dfluorescence microscopy) and relaxivity studies will be conducted on cells under various redox status (oxidative stress or hypoxia) for assessing the sensitivity of the probes. Finally, a thorough investigation of the magnetic coupling between the ligand radical and the lanthanide ions will give us major insight onto the operating mode of the complexes.

Polymer solar cell (PSC) technology is amongst the most powerful and promising in terms of processing cost and simplicity compared to other photovoltaic technologies. There are still, unfortunately, low power conversion efficiency limitations and a major source of instability due to the use of fullerene derivatives as acceptor materials. In the last two years, however, polymer solar cells using a new class of acceptor materials, referred as non-fullerene acceptors (NFA) have gain extremely high attention in the field of PSCs. Indeed, unprecedented increase in power conversion efficiency from 6% to 12% within 18 months, with additional demonstration of fast exciton dissociation at low driving forces at the donor :acceptor interface, demonstrates a high potential of NFA to push PSCs technology for industrial developments. Even more recently, it was shown that limitation of binary donor-acceptor blend approaches can be surpassed by multi-material blend approaches (ternary blends), evidencing the potential of carefully designed complex material associations in the PSCs over the different parameters (increase in open-circuit voltage, photocurrent and very recently also fill factor are improved). In this context, the aim of the NFA-15 project is therefore to develop new highly performing NFA molecules together with appropriate designed ternary blend approaches to reach 15 % of power conversion efficiency at lab level. Furthermore, transfer of lab processes to industrially relevant NFA PSCs printing in air, with efficiency at module level of 10% (8-9% after burn-in) will be developed, which would be an essential step towards a larger range of PSCs application in industry. All these effort in increasing efficiency will be combined with stability study to evaluate and improve the NFA-based solar cells lifetimes to reach long time stability of 7-10 years in products.

Bioelectronics is a fast growing research field aiming at mastering the interfacing of biological systems with electronic devices. Main envisioned applications are linked to medicine (e.g. biosensors for personalized healthcare) and environment survey (e.g. detection of pollutants). The challenge is to convert biological signals, mostly related to ligand binding and ion movements, into electrical signal that can be used by conventional electronic devices. BioNics is an attempt to prove the potential of amyloid fibers for the design and development of bioelectronic nanodevices. These self-assembled protein nanowires possess many advantages. 1) As biological macromolecules, they are likely to be biocompatible. 2) They result from the hierarchical self-assembly of proteins into high aspect-ratio fibers (diameter: 5 nm & length >10 mm) which can interact with biological targets. 3) They can be functionalized in a rationalized manner in many ways with biological macromolecules (other proteins, DNA, sugar…), or organic compounds, nanoparticles…. 4) They can support ionic, protonic, and electronic conductivity. BioNics is set to tackle the long-range charge transport within amyloid fibers of known atomic structure. This will allow detailed interpretations of results and will open possibility for rationalized engineering. Two types of fibers will be studied: (1) “bare” amyloid fibers, called bare nanowires, in order to get insight into the intrinsic conductivity of amyloid fibers and (2) amyloid fibers functionalized with a redox domain, called RedOx nanowires, whose design is bioinspired from the architecture of microbial conductive filaments. The bare nanowires will be studied within dry conditions (dry films). The different conduction regimes and the different types of charge transport (electronic, ionic, protonic…) will be characterized from the macroscale (film) down to the nanoscale (single nanowires). A microelectronic test-vehicle will be specifically developed. This will allow also the first tentative of integration of protein nanowires into electronic devices, resulting in self-assembled protein nanowires-based FETs for instance. The RedOx nanowires more specifically aim at generating bioelectronic devices working in wet conditions within which the dominant conductivity mechanism is electron hopping between redox centers. This should enable electrochemically gated FETs sensitive to various ligands/substrates. In brief, BioNics will constitute a springboard for future enzyme logical circuits, protein-only biosensors and biofuel cells. To the best of our knowledge, BioNics is the only consortium worldwide to have initiated so far such a radically innovative approach. This low TRL 1-3 collaborative project requires the cross-fertilizing association of the very different expertise of its 4 partners. The design of the protein nanowires requires expertise in protein engineering (LCBM). The multiscale (macro/meso/micro/nano-scopic scales) characterization of charge transport properties requires expertise on organic (semi)conductors and extended knowledge in charge transport mechanisms (SyMMES). Electronic measurements down to the single nanowires level and their integration into electronic devices require specific technological expertise as well as equipments and facilities only accessible in world class micro/nanotechnology centers (Leti). The development of electrodes for biosensors and biofuel cells requires expertise in interfacing electrodes made of different materials and in electrochemistry (DCM). Importantly, all partners are based in Grenoble which will be valuable for daily exchanges and interactions required for such an ambitious and multidisciplinary project.