Login / Signup

Fluorescence-Encoded Infrared Vibrational Spectroscopy with Single-Molecule Sensitivity.

Lukas Whaley-MaydaAbhirup GuhaSamuel B PenwellAndrei Tokmakoff
Published in: Journal of the American Chemical Society (2021)
Single-molecule methods have revolutionized molecular science, but techniques possessing the structural sensitivity required for chemical problems-e.g. vibrational spectroscopy-remain difficult to apply in solution. Here, we describe how coupling infrared-vibrational absorption to a fluorescent electronic transition (fluorescence-encoded infrared (FEIR) spectroscopy) can achieve single-molecule sensitivity in solution with conventional far-field optics. Using the fluorophore Coumarin 6, we illustrate the principles by which FEIR spectroscopy measures vibrational spectra and relaxation and introduce FEIR correlation spectroscopy, a vibrational analogue of fluorescence correlation spectroscopy, to demonstrate single-molecule sensitivity. With further improvements, FEIR spectroscopy could become a powerful tool for single-molecule vibrational investigations in the solution or condensed phase.
Keyphrases
  • single molecule
  • density functional theory
  • living cells
  • atomic force microscopy
  • molecular dynamics simulations
  • energy transfer
  • public health
  • molecular dynamics
  • raman spectroscopy
  • solid state
  • fluorescent probe