For transforming nanofluidics from "blind" measurements into an operando discipline guided by microscopy. This visionary approach paves the way for a direct and dynamic understanding of molecular phenomena at the nanoscale, while laying the foundation for improving the performance of nanofluidic devices in molecular sensing, energy harvesting, and neuromorphic computing.

During my PhD, I set out to understand how molecules behave when confined within spaces only a few nanometers wide -- thousands of times thinner than a hair. This process, known as nanofluidic transport, is central to biology, where membranes use nanometer-sized holes to control molecular passage, and to technologies such as filtration, energy conversion, and molecular sensing.

Conventional approaches to nanofluidics typically measure molecular flows exiting the channels and assume that the channel geometry is fixed. I wanted to look more closely: directly inside the nanochannels. This is challenging because light should not reveal details at such small scales, due to diffraction. To overcome this, I used advanced optical strategies: tracking individual molecules with super-resolution and monitoring the channel's shape with interferometry.

Using the fluorescence of a two-dimensional material, I tracked single-molecule dynamics in liquids and under nanometer-scale confinement. Interferometry revealed that artificial 2D nanochannels can deform under voltage, explaining their "memory." Finally, with a single-photon camera, I developed a new method to measure fluorescence lifetimes of single fluorophores attached to biological nanopores used as biosensors.

Together, these approaches show how light can reveal the hidden world of nanofluidic transport.