Hot-band absorption of indocyanine green for advanced anti-stokes fluorescence bioimaging

• DOI: 10.1038/s41377-021-00627-1
• Publication Date: 2021-09-13T07:04:37Z
• Authors: Jing Zhou; Xiaoxiao Fan; Di Wu; Jie Liu; Yuhuang Zhang; Zikang Ye; Dingwei Xue; Mubin He; Liang Zhu; Zhe Feng; Andrey N. Kuzmin; Wen Liu; Paras N. Prasad; Jun Qian
• Keywords: Indocyanine Green; Photon Upconversion; Fluorescence-lifetime imaging microscopy; Absorption band

Abstract Bright anti-Stokes fluorescence (ASF) in the first near-infrared spectral region (NIR-I, 800 nm–900 nm) under excitation of a 915 nm continuous wave (CW) laser, is observed Indocyanine Green (ICG), dye approved by Food and Drug Administration for clinical use. The dependence intensity on light power temperature, together with lifetime measurement, establish this ASF to be originated from absorption thermally excited vibrational level (hot-band absorption), as shown our experiments, which stronger than upconversion widely-used rare-earth ion doped nanoparticles. To test utility NIR-I probe advanced bioimaging, we successively apply it biothermal sensing, cerebral blood vessel tomography stream velocimetry. Moreover, combination L1057 nanoparticles, absorb ICG emit beyond 1100 nm, these two probes generate multi-mode images fluorescent channels single CW laser. One channel used monitor overlapping organs, urinary system & live mouse, while other shows only. Using intraoperative real-time monitoring, such imaging method can beneficial visual guiding anatomy avoid any accidental injury surrounding vessels during surgery.