State of the Art in Cryogenic Infrared Nano-imaging

Optical detection of single molecules mostly relies on their fluorescence because of the high contrast of this technique against the background. However, the majority of native biomolecules such as proteins hardly fluoresce at all, requiring a different approach for their detection. Plasmon-enhanced detection circumvents provides a promising avenue to detect weakly emitting and completely non‐fluorescent species.

In the past decade several mechanisms for plasmon-enhanced single-molecule detection have been demonstrated, including (1) by plasmonically enhancing the emission of weakly fluorescent biomolecules, or (2) by monitoring shifts of the plasmon resonance induced by single-molecule interactions. I will outline recent advances in both approaches at the single-particle and single-molecule level, and will describe their application toward biosensing and single-molecule biophysics.