@article{Diao2015, author = {Shuo Diao and Guosong Hong and Alexander L. Antaris and Jeffrey L. Blackburn and Kai Cheng and Zhen Cheng and Hongjie Dai}, title = {Biological imaging without autofluorescence in the second near-infrared region}, year = {2015}, journal = {Nano Research}, volume = {8}, number = {9}, pages = {3027-3034}, keywords = {fluorescence imaging, nanotechnology, autofluorescence, second near-infrared}, url = {https://www.sciopen.com/article/10.1007/s12274-015-0808-9}, doi = {10.1007/s12274-015-0808-9}, abstract = {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.} }