NANS7009 NANO3/CH5: Luminescent Nanoparticles: Spectroscopic Properties, Colloidal Synthesis, and their Use in Optical Imaging and Thermal Sensing (JSS31) (2 cr)

This interdisciplinary course will focus on luminescent nanoparticles, their properties, synthesis, and application in the biomedical field. After providing a bird-eye view of the different families of luminescent nanoparticles, the spotlight will be on semiconductor nanocrystals and lanthanide-doped nanoparticles. The two families of luminescent nanoparticles will be individually discussed tackling:

- the physics underpinning their spectroscopic properties: concepts introduced in this segment of the course will include electronic bands, bandgap, exciton, Bohr radius, quantum confinement, crystal field, term symbols, Laporte selection rule, photon upconversion, concentration quenching, energy transfer, Stokes shift, photoluminescence lifetime, photon absorption/emission/scattering, photoluminescence quantum yield, and brightness;
- strategies to fine-tune the spectroscopic properties: surface passivation, core/shell structures, alloying, control over energy transfer processes, ion segregation, coupling of lanthanide-doped nanoparticles with other moieties will all be addressed in this section;
- colloidal synthesis approaches: the concepts of precursor, ligand, solvent, and antisolvent will be discussed in the context of nanoparticle synthesis. The meaning of terms like one-pot, hot-injection, thermal decomposition, hydrothermal, controlled precipitation, cation exchange, Ostwald ripening, and nucleation will be thoroughly discussed.

The properties of semiconductor nanocrystals and lanthanide-doped nanoparticles will then be compared, highlighting pros and cons when biomedical applications are sought after, introducing the fundamental concept of biological windows. Methods for transferring hydrophobic nanoparticles into aqueous media and imparting active targeting or stealth properties will subsequently be reviewed. These strategies include ligand removal/exchange, pegylation, phospholipid-assisted encapsulation, silica coating, EDC/NHS coupling, and electrostatic interaction. The success of such approaches will be evidenced/discussed through the recent results in scientific literature concerning imaging and sensing applications.

The students will become acquainted with the fundamental physical properties of semiconductor nanocrystals and lanthanide-doped nanoparticles. They will learn what the parameters that determine the spectroscopic properties of these two families of nanomaterials are and which strategies can be implemented to control on demand said properties. The students will also be introduced to commonly employed colloidal synthesis strategies and surface modification approaches and presented to the most up-to-date applications of the subjects learned in class. In this regard, special emphasis will be given to imaging and thermal sensing. Ultimately, the students will learn what are the main drivers in the design of luminescent nanoparticles for applications in the biomedical context.

M.Sc. or equivalent in chemistry. Final year undergraduate students are welcome to participate in the course.