Luminescence Nanothermometry for the control and understanding of magneto-induced process. Application to biological hyperthermia and heterogeneous catalysis in solution – NANOTHERMOMETRY

The NANOTHERMOMETRY project aims to monitor the local temperature on the contact of nanoparticles heated by activation under an alternating magnetic field using luminescent particles. The two particles will be co-located in order to adjust the distance between the heat source and the measurement point in order to study the temperature gradients at the nanometre scale. These measurements will be carried out under the in vitro conditions of therapeutic hyperthermia and operando of heterogeneous magnetic induction catalysis in solution. The nanothermometers will be selected to fit the temperature (20-300°C) and emission (NIR II) range but also to meet the stability (thermal or chemical) and toxicity constraints of the two applications.
The NANOTHERMOMETRY project aims to combine nano-thermometers and nano-radiators through strategies that allow the determination of the surface temperature of magnetic particles and near-surface temperatures over a few nanometers. The particles will be chemically bound by a varying length ligand whose thermal stability will be verified. This hetero-assembly will allow the co-location of the two types of particles in different cell compartments and for different cell models, and in a catalytic reactor. The project is organised in 5 tasks, in a strong iteration and inter-team collaboration spirit, which will also include a mutualisation of the personnel recruited for the needs of the project. The targeted nano-thermometers will be either spinel, perovskite or garnet oxides doped with rare earth and/or transition elements, or non-toxic quantum dots (task 1). The design of these nanomaterials will be part of an eco-responsible and sustainable approach through a study of their toxicity in a biological environment and their degradation (task 3). The nanothermometers will be classified by temperature range according to their sensitivity to temperature variation (task 2) in order to select the best candidates for each application (adequacy of emission intensity, thermal sensitivity, toxicity, stability). Temperature measurements will be carried out on cells in order to highlight the damage caused by a magnetic hyperthermia treatment (task 4) and under environmental conditions for catalysis (task 5).
The project is very ambitious, from the design of an controlled assembly of nanomaterials and the realization of an experimental set-up dedicated to nanothermometry by luminescence under magnetic field to measurements on concrete examples as close as possible to applications. An interdisciplinary consortium has been set up to cover all the disciplinary fields that the project requires in terms of scientific positioning at the state of the art, but also technical facilities. This ambition is compatible with the duration of the project (48 months) and augurs well for future application of local temperature measurement using luminescent particles.
We can anticipate significant impacts from this project. From an academic point of view, the project will lead to a real reflection on the potential of nanothermometry as a tool for local temperature measurement and temperature gradients in the analytical meaning. We will also join a workshop on temperature and heat transfer measurement issues within the framework of the French Nanometrology Club. In terms of the two targeted applications, in addition to a better understanding of chemical or biological reactivity, the project should allow us to (i) make treatments by magnetic hyperthermia less aggressive and (ii) optimise catalysis by activation under an alternating magnetic field, a promising process for the chemical storage of intermittent energies and the enrichment of biogas with methane.