Fig. 1. Diseases related to mitochondrial dysfunction^[4]

Fig. 2. Schematic diagrams of the interaction between photons and tissues in fluorescence imaging and NIR optical windows. (a) Schematic diagram of the interaction between photons and tissues in fluorescence imaging^[15]; (b) NIR optical windows showing the first (NIR-I) and second (NIR-II) biological windows of the absorption spectra of human skin^[17]

Fig. 3. Fluorescent probes for the detection of ROS. (a) The structure of Mito-Cy-Tfs and its proposed response mechanism towards O2-^[29]; (b) schematic diagram of ROS response structure changes and CO release in TTCO^[30]; (c) design and preparation of NIR-II chemiluminescent nanoparticles OLBB-CLS^[31]; (d) in vivo NIR-II chemiluminescent imaging of OLBB-CLS for arthrosis inflammation mode^[32]

Fig. 4. Fluorescent probes for pH monitoring. (a) pH responsive mechanism of IR-ANNA^[35]; (b) schematic illustration of novel NIR-II Fe-CDs as a nanoprobe for pH biosensing^[37]

Fig. 5. Fluorescent probes for pH monitoring. (a) Synthesis routes of NAB and NRh^[36]; (b) schematic illustration of Cy-Nap as a tumor-targeted theranostic fluorescent probe^[38]

Fig. 6. Fluorescent probes for ATP detection. (a) Schematic procedures for synthesizing NIR-II-BPs and mechanism of NIR-II bioluminescence^[41]; (b) the molecular structure of NIL-RT-ATP and its response to ATP in vitro and in vivo^[42]

Fig. 7. A fluorescent probe for ATP detection based on ZIF-90^[44]. (a) Synthetic procedure for preparing IR-1061 micelle@ZIF-90 nanoprobe; (b) schematic illustration of the nanoprobe's response to ATP; (c) response of the nanoprobe to different ATP concentrations over time

Fig. 8. A fluorescent probe for NAD(P)H detection. (a) Structure of probe A, changes in fluorescence intensity, and changes in fluorescence of different concentrations of NADH in cells^[45]; (b) molecular design of probe KC8 and schematic illustration of revealing the NAD(P)H level highly related to the function of p53 and discriminating the transplanted tumor with HCT-116 p53-/- from HCT-116^[46]