Résumé
Screening of unknown particles, including viruses and nanoparticles, is key
in medicine, industry and pollutant determination. However, existing techniques
require sample a priori knowledge or modification (e.g. fluorescence). Here we
introduce RYtov MIcroscopy for Nanoparticles Identification (RYMINI), a
noninvasive and non-destructive optical approach that is combining holographic
labelfree 3D tracking and high-sensitivity quantitative phase imaging into a
compact optical setup. Dedicated to the characterization of nano-objects in
solution, it is compatible with highly demanding environments such as level-3
biological laboratories. Metrological characterization has been performed at
the level of each single object on both absorbing and transparent particles as
well as on infectious HIV-1, SARS-CoV-2 and extracellular vesicles in solution.
We demonstrate the capability of RYMINI to determine the nature, concentration,
size, complex refractive index and mass of each single particle. We discuss the
application of the method in unknown solution without requiring any knowledge
or model of the particles' response. It paves the way to label-free nano-object
identification in terra incognita.