MaCSE Research - Nanomaterials for health

Light control at the nanoscale is a very important issue in nanoscience. The individual and collective optical properties of nanoparticles make them attractive for labelling and tracking drugs in vivo. Their photochemical properties also make it possible to consider them as a therapeutic agent in photodynamics and photothermics. Finally, their electronic properties offer an elegant solution to simple and sensitive diagnostics.

In order to modulate optical response to a biological stimulus, we are interested in self-assembled superstructures composed of metallic and / or semiconductor nanoparticles. These assemblies are key objects in nanoscience because they combine both optical, chemical and electronics properties of nanoparticles at a functional interface whose collective properties can be modulated on a mesoscopic scale.
Through the optimization of surface chemistry and the synthesis of various ligands, 3D superstructures of metallic or semiconductor nanorods have been obtained, in which interdistance is crucial to control the near-field coupling and optimize their optical response.
More recently, to lead the assembly and control the interdistance, pairs of α-repeat artificial proteins were selected to functionalize nanoparticles.
Thanks to their strong affinity, their specificity of molecular recognition and their 3D structure rigidity, metallic nanoparticles assemblies (ACS Nano 2016) and / or controlled hybrids of quantum dots have been identified.
The future incorporation of biological functionalities on these proteins opens up numerous possibilities of biological applications in the fields of bioimaging and biosensors.

superstructures directed by artificial alpha-repeat proteins

a) QD / QD and b) QD / AuNP superstructures directed by artificial α-repeat proteins

To develop therapeutic nano-agents, we have encapsulated metalbis complexes (dithiolene), exhibiting strong photothermal activity under near infrared (NIR) irradiation (Chem. Commun., 2015; Inorg. Chem., 2016), in the lipid bilayer of unilamellar liposomes (ChemMedChem, 2017) or in biocompatible nanoparticles of block copolymers (J Mater. Chem. B, 2018).
Pulsed NIR irradiation allows precise control of fluorophores or drugs release from these nanostructures in water and in a biological medium. Additional studies have also shown that nanoparticles containing nickel-bis (dithiole) complexes are good agents for photothermal therapy under laser irradiation.
Initial studies have also shown that nickel-bis (dithiole) complexes are effective contrast agents for photoacoustic imaging (Langmuir, 2019). These first results show that nanostructures incorporating metal-bis (dithiolene) complexes show great promise to develop new theranostic agents for the treatment of cancer.

CF release versus time

Controlled release of carboxyfluorescein from unilamellar liposomes containing a Ni-bis complex (dithiolene) hydrophobic under different laser irradiation conditions