Influence of Al3+, Fe3+ and Zn2+ Ions on Phosphorylation of Tubulin and Microtubulo-Associated Proteins of Rat Brain

Construction of water-soluble fluorescent probes supported by carboxymethyl chitosan

Two novel Al3+ fluorescent probes, CMCS-P1 and CMCS-P2, were independently designed and synthesized by modifying the C-2 amino group of carboxymethyl chitosan with benzoyl hydrazide derivatives. The successful incorporation of the benzoyl hydrazide-derived probes was confirmed through FT-IR and 1H NMR spectroscopy. The sensing performance demonstrated that CMCS-P1 and CMCS-P2 could selectively distinguish Al3+ from various metal ions, and the proposed probes both demonstrated excellent water solubility and exhibited a highly selective "turn-on" fluorescence response to Al3+ in pure aqueous solution. CMCS-P1 exhibited a broad linear fluorescence response to Al3+ concentrations from 1.0 to 20.0 µM, featuring a detection limit of 0.33 µM, CMCS-P2 displayed a more limited linear response in the range of 3.0-7.0 µM, with a detection limit of 1.0 µM. Additionally, a small-molecule fluorescent probe P2 was synthesized to explore binding efficiency, and fluorescence imaging in living cells was conducted to successfully detect Al3+ with promising results.