The benefits of near-infrared imaging, both in vitro and in vivo, have generated intense interest in near-infrared microscopy. Most microscopes are outfitted for detection of visible fluorescent wavelengths and not near-infrared wavelengths, so questions may arise about how to perform microscopy with IRDye near-infrared (NIR) fluorescent dyes.
Although LI-COR does not provide microscopy equipment, we have evaluated the near-infrared detection capabilities of microscopes from several manufacturers, particularly in the ~800 nm wavelength region. We are pleased to provide you with guidelines and recommendations for configuring an Olympus or Zeiss microscope for near-infrared detection. The microscope manufacturer can also offer technical assistance.
Unlike conventional visible fluorophores, IRDye fluorophores absorb and emit light in the NIR region of the light spectrum. Since most biomolecules have very low autofluorescence in the NIR region, IRDye 800CW Infrared Dye provides a level of performance not available with visible dyes. Emission of IRDye 800CW Infrared Dye is separated by more than 100 nm from most commonly used dyes (Cy5, for example, emits at 670 nm), so there is no risk of spectral overlap or cross-talk between channels. Bright, clear images with extremely clean backgrounds and excellent sensitivity like those shown are typical with LI-COR's IRDye fluorophores.