Biological imaging without autofluorescence in the second near-infrared region
fluorescence imaging, second near-infrared, nanotechnology, autofluorescence
Fluorescence imaging is capable of acquiring anatomical and functional information with high spatial and temporal resolution. This imaging technique has been indispensable in biological research and disease detection/diagnosis. Imaging in the visible and to a lesser degree, in the near-infrared (NIR) regions below 900 nm, suffers from autofluorescence arising from endogenous fluorescent molecules in biological tissues. This autofluorescence interferes with fluorescent molecules of interest, causing a high background and low detection sensitivity. Here, we report that fluorescence imaging in the 1,500–1,700-nm region (termed “NIR-IIb”) under 808-nm excitation results in nearly zero tissue autofluorescence, allowing for background-free imaging of fluorescent species in otherwise notoriously autofluorescent biological tissues, including liver. Imaging of the intrinsic fluorescence of individual fluorophores, such as a single carbon nanotube, can be readily achieved with high sensitivity and without autofluorescence background in mouse liver within the 1,500–1,700-nm wavelength region.
Tsinghua University Press
Shuo Diao,Guosong Hong,Alexander L. Antaris,Jeffrey L. Blackburn,Kai Cheng,Zhen Cheng,Hongjie Dai, Biological imaging without autofluorescence in the second near-infrared region. NanoRes.2015, 8(9): 3027–3034