Near infrared and colorimetric fluorescence sensor for ultra-selective detection of Cu2+ level with applications in diverse water samples, brain tumor cell and flow injection analysis

Small-Molecule Fluorescent Probes for Binding- and Activity-Based Sensing of Redox-Active Biological Metals

“…Another NIR sensor Cy7C4 (195), based on heptamethine cyanine, was reported by Wanichacheva's group and was used to detect Cu(II) levels in human glioblastoma cells with a 2.45 nM LOD. 338 It is notable that 195 contains thioether groups in the Cu(II)-binding site: this is distinct from the most common N-and O-containing ligands. Dye 196 is a fluorescein-based sensor that also contains a sulfur-bearing ligand, this time comprising bis-(thiophenylmethyl)amine.…”

“…The first among these was reported by Niu and colleagues in 2013. 558 This probe RF (338) was made by linking furfural to rhodamine B hydrazide and showed a turn-on response upon coordination to Cr(III). Due to its amphiphilic properties, 338 was found to be cell permeable in cultured PC12 cells and bind to exogenously added intracellular trivalent chromium ions, as depicted by strong emission from confocal microscopy images.…”

“…The probe was applied to HeLa cells treated with Cu­(II). Another NIR sensor Cy7C4 ( 195 ), based on heptamethine cyanine, was reported by Wanichacheva’s group and was used to detect Cu­(II) levels in human glioblastoma cells with a 2.45 nM LOD . It is notable that 195 contains thioether groups in the Cu­(II)-binding site: this is distinct from the most common N- and O-containing ligands.…”

Synthesis and characterization of a rhodamine derivative as a selective switch-on fluorescent sensor for Cu2+ ions in aqueous PBS buffer and living cells

“…18 Inductively coupled plasma-mass spectrometry (ICP-MS), atomic absorbance, colorimetry, flow injection, and electrochemical approaches are some of the current methods used for the measurement of Cu 2+ ions. [19][20][21][22][23][24] However, these methods are expensive, not readily available, and require highly specialized personnel. Therefore, the development of small-molecular fluorescent probes with high sensitivity and selective sensing of Cu 2+ remain an important area of research.…”