Figure 1

(A) Developed electrochemical sensor with ratiometric signal output for the reliable assaying of O2·- concentrations in a normal rat brain and a diabetic rat brain upon cerebral ischemia. DPV curves observed at CFME/SWCNT/MB+ND for O2·- detection in the hippocampus of normal rat brain (B), and diabetic rat brain (C) under different ischemia time. Reproduced with permission of Ref. 36. Copyright 2021 Analytical Chemistry. (color on line)

Figure 2

(A) Working principle of MPS-1 and MHS-2 for simultaneous assaying of H2S and H2Sn in a live mouse brain and further investigation in the activation of the TRPA1 channel by H2Sn and H2S. (B) Typical DPVs obtained at CFME/mAu/MPS-1+MHS-1 in a mouse brain before (a) and after (b) MCAO for 2.0 h. (C) The levels of H2S, H2Sn and TRPA1 protein in hippocampus upon MACO with different hours. Reproduced with permission of Ref. 24. Copyright 2019 Angewandte Chemie-International Edition. (color on line)

Figure 3

(A) The synthetic route for FDCA molecule. (B) Assembly of the FDCA molecules onto CFME through three strategies to form CFME/Au/AT/FDCA, CFME/Au/AS/FDCA, and CFME/Au/PA/FDCA electrodes. (C) The representative SEM images of CFME/Au electrode and enlarged Au nanoparticles onto CFME and the working principle of the developed sensor for determination of Fe2+. Reproduced with permission of Ref. 41. Copyright 2020 Angewandte Chemie-International Edition. (color on line)

Figure 4

(A) Illustration for multi-fiber microarray and measurements in the mouse brain. (B) SEM images of DPACE (top) and EDACE (bottom). (C) EDX analysis images of the selected areas of Au (yellow) and GO (blue) on DPACE (top) and EDACE (bottom). (D) Fluorescence images of DPACE and EDACE after immersed in 20 mg·mL-1 FITC-BSA solution for 2 h. (E) Molecular structures of METH (left), M18C6 (middle) and MBAPTA (right), and the modification of three ligands onto electrode surfaces. (F) The potential changes (vs. Ag/AgCl) obtained at METH-E (left), M18C6-E (middle), and MBAPTA-E (right) with continuously increasing concentration of Ca2+ and decreasing concentration of Ca2+ in aCSF. Reproduced with permission of Ref. 26. Copyright 2021 Angewandte Chemie-International Edition. (color on line)

Figure 5

(A) Specific recognition molecules for K+, Na+, pH, and Ca2+. (B) Schematic structures of 5-channel ion selective microelectrode arrays (5-ISMEA) and 8-channel M-ISMEA (K-ISMEA, Ca-ISMEA, Na-ISMEA or H-ISMEA). (C) LFP signals recorded in a live rat brain upon seizure, and the developed ECPM for real-time mapping and simultaneous quantification of multi-ions in the brain of a freely moving rat. (D) Potential responses of 5-ISMEA toward KCl, NaCl, CaCl2, and HCl in 0.1 mol·L-1 Tris-buffer. (E) 3D surface plots of potential separation (ΔEISE) or K+, Na+, Ca2+, pH responses of KISME, Na-ISME, Ca-ISME, and H-ISME as a function of one kind of ion and the other three ions. Reproduced with permission of Ref. 25. Copyright 2020 Angewandte Chemie-International Edition. (color on line)