Self-assEmbled QUantum gOld clusters for bIophotonic Applications – SEQUOIA

Gold Quantum Clusters (GQCs) are a class of ultra-small particles presenting tunable photoluminescence (PL) in the first (NIR-I) and second (NIR-II/SWIR) near-infrared windows, making them appealing tracers for high resolution imaging of blood vasculature in mice, as demonstrated by Team 1. Interestingly, we also recently showed that the absorbance and PL in the NIR windows is dramatically boosted when GQCs self-assemble. The main objectives of our project are now to make the proof of concept that such self-assembly can be obtained and controlled by in vivo bio-orthogonal click chemistry after successive intravenous administrations of biocompatible polymer chains and GQCs bearing complementary functions such as strained cyclooctynes (DBCO) and azides. After in situ generation, the nano-assemblies will present enhanced biophotonic properties. Thanks to the presence of cRGD-peptide targeting ligands on the polymer, non-invasive diagnostic applications will lead to the sensitive detection of angiogenesis and of a specific biomarker expressed on activated neo-endothelial cells (integrin ?vß3).
Controlled formation and the properties of the nano-assemblies will be studied in increasingly complex environments: serum-containing solutions, microfluidic devices, 2D/3D cell culture and then in mice carrying proangiogenic cellulose sponges implanted subcutaneously. All methods are currently available in our laboratories.
The versatility and new optical properties of this platform could be exploited for the definition of the next generation of theranostic agents, but also eventually biophotonic sensors and optoelectronic devices.