A novel hydrophilic fluorescent probe for Cu²⁺ detection and imaging in HeLa cells

Abstract

Probe BNQ was successfully used for detection of exogenous Cu2+ in cells using a rare ESDPT sensing mechanism.

Construction of Chitosan-Modified Naphthalimide Fluorescence Probe for Selective Detection of Cu2+

“…Different probes derived from chitosan-based naphthalimide or naphthalimide displayed different characteristics, exhibiting fluorescence enhancement or quenching, which demonstrated a quick response [ 27 , 28 , 29 ], potential application value [ 27 , 30 , 31 , 32 ] and high sensitivity [ 27 , 29 , 31 ]. Meanwhile, various drawbacks could not be ignored, such as the organic solvent for dissolving [ 27 , 28 , 29 , 30 , 31 , 32 , 33 ], the long equilibrium time [ 31 , 32 ], narrow detection ranges [ 28 ], and low sensitivity [ 29 , 31 ]. Our probe P was a valuable probe with a fast equilibrium time, wide detection range, good reversibility, a visible light for excitation and emission.…”

A novel “on–off–on” near-infrared fluorescent probe for Cu2+ and S2− continuous detection based on dicyanoisoflurone derivatives, and its application in bacterial imaging

“…S6,† we find that the curve has an inflection point at 0.5, which indicates that a 1 : 1 stoichiometric complex is formed between DL and Cu 2+ . Then, according to the Benesi–Hildebrand equation, 25 as shown in Fig. S7,† the binding constant between DL and Cu 2+ is calculated to be 2.57 × 10 5 M −1 .…”

“…At present, organic fluorescent probes designed for the detection of Cu 2+ based on different fluorophores have been reported, including coumarin, 20 fluorescein, 21 phthalazine, 22 imidazole 23 and BODIPY. 24 However, most probes emit wavelengths in the short-wave range, 25,26 so they are less penetrating to biological tissues and can only be used to detect Cu 2+ , while applications at the biological level are relatively rare. NIR fluorescent probes have the characteristics of noise reduction, low background interference, small tissue damage to organisms, good penetration, and reduced tissue light scattering, 27,28 and have become a research hotspot at home and abroad.…”

Review of the detection of metal ions using fluorescent probes

“…The UV-vis absorption study shows that absorption peak between the range 300nm and 500nm increased with increasing Cu 2+ concentration, accompanying a color change visible to naked eye of bright yellow to colorless. Fluorescence titration shows that fluorescence decreased from 520nm with increasing Cu 2+ concentration, with color change from green to colorless [5]. Selectivity experiments shows that the addition of metal ions other than copper did not cause a change to the fluorescence spectrum.…”