Novel indoleoxazine derivative cyanide ion probe: Detection applications and cell-imaging studies

A novel pyrazole-pyrazoline fluorescent probe for the detection of Cu2+ and Fe3+ in living cells

Copper ions and iron ions are abundant metal ions in nature, and are also essential trace elements in the human body, playing a crucial role in various physiological activities. However, the detection of copper and iron ions also poses significant challenges. This article reports the synthesis of a novel fluorescent probe X2 based on the pyrazole structure, which exhibits unique optoelectronic properties, strong biological activity, good selectivity, excellent detection limit, high sensitivity, and its structure was characterized by 1H NMR, 13C NMR, and HR-ESI-MS. The obtained probe exhibits AIE characteristics, and its mechanism was analyzed through infrared spectrum and theoretical calculations. Finally, through cytotoxicity and cell imaging experiments, it was demonstrated that the probe has low toxicity and can be used in the field of biology. This article provides a new approach for detecting copper and iron ions using fluorescent probes with pyrazole structures.

Carbazole-based mitochondria-targeted fluorescent probes for in vivo viscosity and cyanide detection in cells and zebrafish

Cells of most eukaryotic species contain mitochondria, which play a role in physiological processes such as cellular senescence, metabolism, and autophagy. Viscosity is considered a key marker for many illnesses and is involved in several crucial physiological processes. Cyanide (CN-) can target cytochrome-c oxidase, disrupting the mitochondrial electron transport chain and causing cell death through asphyxiation. In this study, a fluorescent probe named HL-1, which targets mitochondria and measures viscosity and CN- levels, was designed and synthesized. HL-1 is viscosity-sensitive, with a linear correlation coefficient of up to 0.992. In addition, HL-1 was found to change color substantially during a nucleophilic addition reaction with CN-, which has a low detection limit of 47 nM. HL-1 not only detects viscosity and exogenous CN- in SKOV-3 cells and zebrafish but also monitors viscosity changes during mitochondrial autophagy in real time. Furthermore, HL-1 has been used successfully to monitor changes in mitochondrial membrane potential during apoptosis. Endogenous CN- in plant samples was quantified. HL-1 provides new ideas for studying viscosity and CN-.