Fluorescent Probe For Cu2 Research Articles

Fluorescence-enhanced microfluidic sensor for highly sensitive in-situ detection of copper ions in lubricating oil

Sensitive on-line detection of Cu2+ in lubricating oil of marine power plant is important for displaying equipment wear status and fault pre-judgment in real time. However, there are few reports on in-situ, portable and highly sensitive Cu2+ detection devices in organic media before. In this report, CsPbBr3 perovskite quantum dots (PQDs) are employed as fluorescence probe for Cu2+ detection in microfluidic chip. The size effect of the CsPbBr3 QDs on the detection performances is firstly investigated. To obtain preferable sensitivity and detection limit, polymethyl methacrylate opal photonic crystals (PMMA OPCs) film is developed as microfluidic sensor substrate, which can tremendously improve the fluorescence intensity of PQDs as high as 26-fold. The enhancement effect can be attributed to the coupling between photonic crystal stopband effect and the excitation light field. Moreover, the use of photomultiplier module for fluorescence signal measurement enables the detection device to be portable. The novel strategy offers the advantages of higher sensitivity (8.62 μM–1) and lower detection limit (0.40 nM). Otherwise, this sensor also provides wide detection range and good selectivity, thus, it will have potential in oil quality in-situ detection and mechanical wear prediction in the future.

A Highly Sensitive and Selective “Off-On” Fluorescent Probe for Cu2+ Based on Rhodamine B Hydrazone

A Highly Sensitive and Selective “Off-On” Fluorescent Probe for Cu²⁺ Based on Rhodamine B Hydrazone

Progress in Fluorescent Probes for Cu2+ and Anions, Neutral Molecules Sequential Recognition

Progress in Fluorescent Probes for Cu²⁺ and Anions, Neutral Molecules Sequential Recognition

An “Off-On” Near-Infrared Fluorescent Probe for Cu2+ Detection in Living Cells

An “Off-On” Near-Infrared Fluorescent Probe for Cu²⁺ Detection in Living Cells

New ferrocene-triazole derivatives for multisignaling detection of Cu2+ in aqueous medium and their antibacterial activity.

Ferrocene-based naphthalene or quinoline receptors 1-4 linked by triazole were designed and synthesized. Their recognition properties of metal cations have been investigated systematically in aqueous environment. Upon addition 1 equiv. of Cu2+ ion, receptors 1 (C23H19FeN3O) and 2 (C22H18FeN4O) showed fluorescent turn-off, enhanced absorption and color variations. At the same time, receptor 1 also caused the perturbation of redox potential after addition 1 equiv. of Cu2+ ion. Therefore, receptors 1 and 2 behaved as naked-eye chemosensors and fluorescent probes for Cu2+ without interference by other ions and with low detection limit. In addition, receptor 1 could also be considered electrochemical sensor for Cu2+ having excellent sensitivity and selectivity. However, increasing the molecules flexibility resulted in the lower selectivity of ion recognition in the case of receptors 3 (C24H21FeN3O) and 4 (C23H20FeN4O). Furthermore, this series of compounds were nontoxicity and receptor 1 exhibited certain antibacterial activity.

Crown daisy leaf waste–derived carbon dots: A simple and green fluorescent probe for copper ion

In this paper, N‐doped carbon quantum dots (N‐CDs) were fabricated using crown daisy leaves, a kitchen waste, as carbon source. The synthesized N‐CDs possessed abundant surface functional groups, such as hydroxyl, carboxyl, and amino groups, and had good dispersibility in water. Because of the special fluorescence quenching property toward Cu2+, the synthesized N‐CDs can be exploited as an effective label‐free fluorescent probe for Cu2+ determination. The possible fluorescence sensing mechanism considered the selective coordination interaction between Cu2+ ion and the hydroxyl, carboxyl, and amino groups of the N‐CDs. The control experiments also showed that the N‐doped aromatic C–N heterocycle structure played a crucial role in selective sensing of Cu2+. The decrease in fluorescence efficiencies was linearly related with the Cu2+ concentrations in the range of 10.0nM to 120.0nM, with a response limit of 1.0nM. The prepared probe was also applied for Cu2+ determination in real river water.

An efficient chemodosimeter for Cu(II) ions based on hydrolysis of fluorescein and its utility in live cell imaging

A new NBD-based chemodosimeter system bearing fluorescein derivative has been synthesized for the detection of Cu(II) ions. The spirocyclic form of molecular system bearing a cleavable active bond performs as a fluorescent probe for Cu2+ ion selectively towards other metal ions. The sensing mechanism of Cu2+ with fluorescein hydrazide supports hydrolytic cleavage of the amide bond, hence causing the release of fluorophore (fluorescein) and enhancement of fluorescence. The proposed chemodosimeter displays the selective detection of Cu2+ ion and has been effectively utilised for live cell imaging of Cu2+ in HeLa cells.

Fluorescent probe for Cu2+ and the secondary application of the resultant complex to detect cysteine.

A special fluorescent probe has been developed, one that demonstrated excellent “off-on-type” change in fluorescence with high selectivity toward Cu2+. Interestingly, the probe–Cu2+ complex could detect cysteine due to the ability of this amino acid to strongly coordinate Cu2+, and no obvious interference was observed from other amino acids and anions. According to the proposed mechanism, addition of cysteine induced decomplexation of the probe–Cu2+ form. Furthermore, the results of confocal microscopy experiments demonstrated the potential of using the probe to image Cu2+ in living cells and mice.

A high-contrast colorimetric and fluorescent probe for Cu2+ based on benzimidazole-quinoline

A novel colorimetric and fluorescent probe based on benzimidazole-quinoline (BMQ) was designed and synthesized. The probe exhibited high sensitivity and selectivity for Cu2+ over other cations. In addition, the color and fluorescence changes induced by Cu2+ exhibit sharp contrast. An abrupt and obvious absorption spectra shift (around 132nm) in the visible light range (400–650nm) is observed. The colorimetric ratio A550/A418 of absorption and the concentrations of Cu2+ ranging from 0 to 100μmol/L show excellent linear relationship. Furthermore, the probe BMQ undergoes a complete quenching of fluorescence entered at 610nm (98% quenching) in the present 10eq Cu2+. The detection limit of BMQ for Cu2+ was far lower than the maximum allowable level of the U.S. Environmental Protection Agency limit (20μM) for drinking water.

A rhodamine 6G derivative as “turn-on” fluorescent probe for Cu2+. Spectroscopy, single crystal structure and DFT calculations

In order to achieve an effective “turn-on” fluorescence detection of Cu2+, a rhodamine 6G-based sensor [1-phenyl-3-methyl-5-hydroxypyrazole-4-benzoyl(rhodamine 6G) hydrazone, 1] was prepared. Fluorescence and UV–Vis absorption titration, detection limit, single crystal structure, binding mode, and quantum mechanical calculation studies were also discussed in detail. Sensor 1 showed highly selectivity and sensitivity to Cu2+ among common cations (Na+, K+, Mg2+, Ca2+, Mn2+, Co2+, Ni2+, Zn2+, Cd2+, Cr3+, Fe3+ and Cu2+) in acetonitrile. Upon addition of Cu2+, a new absorption band at 523nm, and a strong emission band centering at 557nm appeared in 1 solution. Relevant solution changed from colorless to purple, and an obvious orange fluorescence emission was given. A maximum fluorescence enhancement of 250 times at 557nm could be made by addition of 6 equivalent of Cu2+. The fluorescence detection limit was calculated to be 2.5μM (0.20ppm) for Cu2+, and 1:1 stoichiometry between Cu2+ and 1 was proved. In the single crystal of 1–Cu2+ complex, rhodamine moiety exhibited an open cycle form. We believe 1 can be a good candidate for the fluorescence detection of Cu2+.

A highly selective and sensitive fluorescent probe for Cu2+ based on a novel naphthalimide-rhodamine platform and its application in live cell imaging.

Copper plays important roles in a variety of fundamental physiological processes. At the cell organelle level, aberrant copper homeostasis in lysosomes can lead to various serious diseases. Herein, a bifluorophore-based, lysosome-targetable Cu2+-selective ratiometric fluorescent probe (V) has been synthesized by reasonable design. The probe V shows high selectivity toward Cu2+ ions over other cations and exhibits high sensitivity (1.45 nM) for the detection of Cu2+ ions. Meanwhile, the probe is cell permeable and suitable for ratiometric visualization of lysosomal Cu2+ in the living cell.

A highly sensitive and fast responsive naphthalimide-based fluorescent probe for Cu2+ and its application

The response of the probe L to Cu2+ is reversible and very fast (20 s). L has a low detection limit of 49 nM and was used for imaging of Cu2+ in MCF-7 cells with satisfying results. The sensor L can be analyzed with a molecular logic gate.

Coumarin-naphthol conjugated Schiff base as a “turn-on” fluorescent probe for Cu2+ via selective hydrolysis of imine and its application in live cell imaging

Abstract An off-on fluorescent probe (CuCIN), coumarin-naphthol linked by an imine group, for detecting Cu2+ in DMSO-HEPES buffer (1:99, v/v) solution was successfully developed. Mechanism studies suggested that CuCIN firstly formed a complex with Cu2+ in a 1:2 metal-to-ligand ratio, and then 60-fold fluorescence enhancement was observed when Cu2+ promoted the imine hydrolysis to release the fluorescence compound 7-diethylaminocoumarin-3-aldehyde. This probe displayed desired properties such as high selectivity toward other metal ions, low detection limit (12.7 nM) and low cytotoxicity. Bio-imaging study revealed that the new probe CuCIN could be applied for imaging living cells with good cell permeability. We hope to apply this probe in the biomedical research field for the imaging of disease-relevant Cu2+.

A Readily-Synthesized Fluorescent Probe Based on N, N-Bis (Pyridin-2-Ylmethyl) Aniline for Copper(II) Detection in Aqueous Solution.

In this paper, probe 1 based on N, N-bis (pyridin-2-ylmethyl) aniline is prepared as an effective fluorescent probe for Cu2+. It exhibits good sensitivity and selectivity for Cu2+ over other metal ions in aqueous solution. The detection limit of probe 1 is 56nM. Furthermore, probe 1 is pH-insensitive under near-neutral conditions and can work well in environmental samples.

Rational Design of a Water-Soluble, Lipid-Compatible Fluorescent Probe for Cu(I) with Sub-Part-Per-Trillion Sensitivity.

Fluorescence probes represent an attractive solution for the detection of the biologically important Cu(I) cation; however, achieving a bright, high-contrast response has been a challenging goal. Concluding from previous studies on pyrazoline-based fluorescent Cu(I) probes, the maximum attainable fluorescence contrast and quantum yield were limited due to several non-radiative deactivation mechanisms, including ternary complex formation, excited state protonation, and colloidal aggregation in aqueous solution. Through knowledge-driven optimization of the ligand and fluorophore architectures, we overcame these limitations in the design of CTAP-3, a Cu(I)-selective fluorescent probe offering a 180-fold fluorescence enhancement, 41% quantum yield, and a limit of detection in the sub-part-per-trillion concentration range. In contrast to lipophilic Cu(I)-probes, CTAP-3 does not aggregate and interacts only weakly with lipid bilayers, thus maintaining a high contrast ratio even in the presence of liposomes.

Novel coumarin-based fluorescent probe for selective detection of Cu(II)

We report an efficient and convenient method for preparing nitro-3-carboxamide coumarin derivatives, proposed as novel fluorescent chemosensor, through microwave irradiation. This compound can be used as fluorescent probe for Cu2+ with selectivity over other metal ions in aqueous solution. The fluorescence of 6-nitro-N-[2-(dimethylamino)ethyl]-2-oxo-2H-chromene-3-carboxamide(3) is the highest in the presence of Cu2+, with stronger excitation at λ=320nm than for the other cations tested.

A Novel Multi-functional Fluorescent Probe for Cu2+, Fe3+ and Ag+ Based on a Pyrimidine Thiourea Derivative

A Novel Multi-functional Fluorescent Probe for Cu2+, Fe3+ and Ag+ Based on a Pyrimidine Thiourea Derivative

A Novel Naked-Eye and Dual-Channel Responsive Fluorescent Probe for Cu2+Based on 3,4-Disubstituted-1,8-naphthalimide

A new 3,4-disubstituted-1,8-naphthalimide derivative H1 was designed and synthesized as a selective fluorescent probe for Cu2+ over miscellaneous metal ions in aqueous media. Upon mixing with Cu2+ in CH3OH:H2O (1:1, volume ratio), the increase of fluorescence intensity and a bathochromic shift of absorbance of H1 could be observed with a notable color response (changing from yellow to pink). Furthermore, Cu2+ coordinates to the probe H1 and a 1:1 metal-ligand complex was formed.

Development and cell imaging applications of a novel fluorescent probe for Cu2+

A reactivity-based fluorescent probe was utilized to selectively detecting Cu2+ in aqueous solution and living cell.

Silica nanoparticles doped with a europium(III) complex and coated with an ion imprinted polymer for rapid determination of copper(II)

We have prepared highly monodisperse silica spheres doped with an Eu(III) complex and coated them with a nanoshell of a copper-imprinted polymer. The silica cores have a diameter of 200 nm, and the nanoshells have a thickness of 10–30 nm. The nanoparticles were characterized by means of scanning electron microscopy and transmission electron microscopy. The material is shown to be a viable fluorescent probe for Cu(II) ions. The surface molecular imprint renders the nanoprobe sensitive and selective. It was successfully applied to the detection of Cu(II) and gave a linear fluorescent response in the 10–100 μM concentration range. Compared to other methods, this one features high selectivity, sensitivity, low cost and ease of operation. We assume that this assay is applicable to routine trace determination of Cu(II) in water or biological environments. By adopting the appropriate functional monomers, cross-linking agents and template ions, the method can potentially be used to fabricate a highly selective imprinted probe for other heavy and transition metal ions.