Laser Spectroscopic Tools for Nano-Biophotonics

Biophotonics is a vibrant interdisciplinary field exploring the interaction between electromagnetic radiation and biological materials such as sub-cellular structures and molecules in living organisms. Biophotonics research leads to applications in agriculture and life sciences and produces tools for medical diagnostics and therapies. Working in this general field, we have recently made advances toward ultrasensitive Raman-spectroscopic probing of viruses. Our approach is based on laser spectroscopy aided by plasmonic nanoantennas, as in tip-enhanced Raman spectroscopy (TERS). An additional enhancement in sensitivity and speed is obtained by employing the femtosecond adaptive spectroscopic technique (FAST) for coherent anti-Stokes Raman scattering (CARS). The combined approach shows promise for non-destructive label-free bioimaging with molecular-level sensitivity and with spatial resolution down to a fraction of a nanometer.