Professor Dr. María García-Parajo, ICFO – The Institute of Photonic Sciences, Barcelona, Spain

Spatiotemporal Organization of Membrane Receptors in Living Cells Using Nanophotonic Tools

The quest for optical imaging of biological processes at the nanoscale has driven in recent years a swift development of a large number of nanoscopy techniques based on far-field optics. These, so called, super-resolution methods are providing new capabilities for probing biology at the nanoscale by fluorescence. While these techniques conveniently use lens-based microscopy, the attainable resolution and/or localization precision severely depend on the sample fluorescence properties. True nanoscale optical resolution free from these constrains can alternatively be obtained by interacting with fluorophores in the near-field. Indeed, near-field scanning optical microscopy (NSOM) using subwavelength aperture probes is one of the earliest approaches sought to achieve nanometric optical resolution. More recently, photonic antennas have emerged as excellent alternative candidates to further improve the resolution of NSOM by enhancing electromagnetic fields into regions of space much smaller than the wavelength of light. In this contribution, I will describe our efforts towards the fabrication of different nanoantenna probe configurations as well as 2D antenna arrays for applications in nano-imaging and spectroscopy of living cells with unprecedented resolution and sensitivity. I will also discuss the combination of far-field super-resolution nanoscopy and multi-colour single particle tracking to elucidate the multi-scale spatiotemporal organisation of immune receptors on living cell membranes in relation to cell function.