Fluorescent Probe For Hypochlorite Research Articles

Facile access to a methylthiocoumarinyl formate as highly selective and sensitive fluorescent probe for hypochlorite

Facile access to a methylthiocoumarinyl formate as highly selective and sensitive fluorescent probe for hypochlorite

A Ratiometric Fluorescent Probe for Hypochlorite and Lipid Droplets to Monitor Oxidative Stress.

Mitochondria are valuable subcellular organelles and play crucial roles in redox signaling in living cells. Substantial evidence proved that mitochondria are one of the critical sources of reactive oxygen species (ROS), and overproduction of ROS accompanies redox imbalance and cell immunity. Among ROS, hydrogen peroxide (H2O2) is the foremost redox regulator, which reacts with chloride ions in the presence of myeloperoxidase (MPO) to generate another biogenic redox molecule, hypochlorous acid (HOCl). These highly reactive ROS are the primary cause of damage to DNA (deoxyribonucleic acid), RNA (ribonucleic acid), and proteins, leading to various neuronal diseases and cell death. Cellular damage, related cell death, and oxidative stress are also associated with lysosomes which act as recycling units in the cytoplasm. Hence, simultaneous monitoring of multiple organelles using simple molecular probes is an exciting area of research that is yet to be explored. Significant evidence also suggests that oxidative stress induces the accumulation of lipid droplets in cells. Hence, monitoring redox biomolecules in mitochondria and lipid droplets in cells may give a new insight into cell damage, leading to cell death and related disease progressions. Herein, we developed simple hemicyanine-based small molecular probes with a boronic acid trigger. A fluorescent probe AB that could efficiently detect mitochondrial ROS, especially HOCl, and viscosity simultaneously. When the AB probe released phenylboronic acid after reacting with ROS, the product AB-OH exhibited ratiometric emissions depending on excitation. This AB-OH nicely translocates to lysosomes and efficiently monitors the lysosomal lipid droplets. Photoluminescence and confocal fluorescence imaging analysis suggest that AB and corresponding AB-OH molecules are potential chemical probes for studying oxidative stress.

Visualizing stimulus-responsive dual-ligand fluorescent probes for hypochlorite: A novel strategy for real application in tap water.

As an effective ingredient of disinfectants, ClO- inevitably remains in water, which induces potential health hazards such as lung damage and kidney disease. In this study, we synthesized stimulus-responsive dual-ligand luminol-Tb-GMP coordination polymer nanoparticles (luminol-Tb-GMP CPNPs) as highly selective fluorescent probes for the real-time and visual detection of ClO- . CPNPs consist of Tb3+ , a nuclear metal, that coordinates with GMP and luminol, an auxiliary ligand. GMP can be oxidized by ClO- and damage its structure, resulting in fluorescence quenching of CPNPs. The two-ligand CPNPssensor has a rapid fluorescent response, significant fluorescent color change, and high sensitivity, with a linear range of 2-18 μM and a detection limit of 0.14 μM. It has been successfully used to detect ClO- in tap water, fountain water, and drinking water. Simultaneously, the portable filter paper strip was prepared to expand the range of applications outside the laboratory, which will provide a promising application for the real-time and semiquantitative analysis of ClO- .

Dual-Responsive Ratiometric Fluorescent Probe for Hypochlorite and Peroxynitrite Detection and Imaging In Vitro and In Vivo

Hypochlorite (ClO-) and peroxynitrite (ONOO-) are two crucial highly reactive oxygen/nitrogen species, which interplay with each other, and are implicated in numerous pathophysiological processes. The simultaneous detection of ClO- and ONOO- is immensely significant in evaluating the occurrence and progress of related diseases. Herein, a dual-responsive ratiometric fluorescent probe PTZ-H for the separate and simultaneous detection of ClO- and ONOO- was designed and synthesized. In this probe, the phenothiazine-based coumarin moiety was chosen as the ClO- responsive fluorescent fragment, and the precursor of 2-(benzo[d]thiazol-2-yl)aniline was employed as the sensor for ONOO-. The PTZ-H emitted red fluorescence (640 nm) can switch to green (520 nm) and turn on blue fluorescence (450 nm) in response to ClO- and ONOO-, respectively. This allowed the specific recognition and ratiometric quantification of ClO- and ONOO- with the detection limits of 17 and 21 nM, respectively. Notably, confocal laser scanning microscopy revealed that the PTZ-H probe could target-specifically image ClO- and ONOO- in living RAW 264.7 cells, zebrafish, and tissues with distinct fluorescence signals. With the aid of this single fluorescent probe, the endogenous accumulation of ClO- and ONOO- in inflammatory RAW 264.7 cells and zebrafish can be monitored through two distinct emission channels with fast responses. Moreover, the large fluorescence signal interval, high selectivity, and good biocompatibility may enable its application in deciphering the distribution and correlation of ClO- and ONOO- engaged in biological activity.

A highly selective A–π–A “turn-on” fluorescent probe for hypochlorite in tap water

A nitro group-bearing fluorescent probe with the electronic structure of “A–π–A” showed high selectivity and sensitivity for hypochlorite.

A dual-site colorimetric fluorescent probe for rapid detection of hydrazine/hypochlorite and its application in two-photon fluorescent bioimaging

A colorimetric two-photon multianalyte sensor with spirobifluorene motif was developed. Along with the addition of hypochlorite/hydrazine to a solution of the probe, a colorimetric change from yellow to colorless and a fluorescence enhancement (Under 365 nm UV light) can be observed by ‘naked-eye’. The detection limits are 28 nM for hypochlorite and 12 nM for hydrazine, respectively. The molecule has large two-photon cross-section value of 220GM and has been successfully applied to two-photon imaging of hypochlorite / hydrazine in live cells. As far as we know, a two-photon fluorescent probe capable of detecting reactive oxygen species and reducing agent, and a colorimetric two-photon fluorescent probe for hypochlorite is reported for the first time. In addition, the detection limit for hydrazine is much lower than those of most hydrazine fluorescent probes reported in the literature.

A dicyanoisophorone-based fluorescent probe for hypochlorite with a fast response and its applications in bioimaging.

One kind of phenolic substituted dicyanoisophorone derivative (Is-OL) has been designed and successfully synthesized for the detection of hypochlorite in water samples, test strips and living HeLa cells. The probe Is-OL showed high sensitivity and selectivity to hypochlorite over other competitive ROS and metal ions. Moreover, Is-OL can react instantaneously with hypochlorite (<5 s) while exhibiting a significant color change from yellow to colorless, which makes "naked-eye" detection possible with a low detection limit (0.095 μM). The results based on water tests and living HeLa cell experiments showed that Is-OL could be applied as a potential candidate for the detection of hypochlorite.

Highly selective turn-on fluorescent probe for hypochlorite and viscosity detection

Due to the important role of hypochlorous acid (HOCl) in immune prevention of bacteria towards living organisms and its variations may be related to the change of intracellular viscosity, it is significant to design fluorescent probe to accurately analyze changes for detecting HOCl and viscosity simultaneously. In this paper, water-soluble, very fast-responsive fluorescent probes PTZ-TPP and PTZ-MP based on phenothiazine moiety were developed. The sensing mechanism of the probe with HOCl was elucidated by emission spectra at long and short excited wavelength 480 and 380 nm, and the oxidation structure OPTZ-TPP, sulfur peroxide structure O3PTZ-TPP as well as carbon-carbon double bond cleavage structure OCy-TPP were confirmed by ESI-MS analysis. The detection limit (LOD) of probe PTZ-TPP and PTZ-MP was evaluated to be 14.7 and 19.4 nM respectively. Moreover, the probe PTZ-MP was further used for the detection of viscosity. Furthermore, cell imaging of PTZ-TPP towards HOCl was conducted. And it is expected to be used in simultaneous determination of HOCl and viscosity in intracellular.

A dual-response ratiometric fluorescent probe for hypochlorite and hydrazine detection and its imaging in living cells.

In this work, a dual-response ratiometric fluorescent probe (E)-3-(5-(2-nitrovinyl)thiophen-2-yl)-9-phenyl-9H-carbazole (NTPC) for high selectivity and sensitivity detection of ClO- and N2H4 was successfully developed. This probe NTPC showed ratiometric fluorescent response to ClO- and N2H4, which induces obvious naked-eye color changes, respectively. In addition, the NTPC for ClO- and N2H4 detection displayed low detection limits of 71.4nM and 0.6μM, respectively. And the sensing mechanism of NTPC with ClO- and N2H4 was well confirmed by 1H NMR and HR-MS spectra. Moreover, this novel probe was applied to monitoring and differentiating ClO- and N2H4 in living cells, and exhibits good biocompatibility and low cytotoxicity.

A novel fluorescent probe with extremely low background fluorescence for sensing hypochlorite in zebrafish.

Development of an efficient fluorescent probe for sensing hypochlorite in water samples and biological samples is highly demanded. However, the currently reported fluorescent probes for hypochlorite frequently suffered from the problem of high background fluorescence. Herein, based on the combined effect of two different fluorescence quenching groups, we rationally developed a novel fluorescent probe for hypochlorite with extremely low background fluorescence. Notably, due to the doubly quenching groups, the probe could even keep low background fluorescence in a solution with high viscosity. Furthermore, the probe displayed highly sensitive and selective response to hypochlorite, with the detection limits calculated to be 10.5nM. Practical application demonstrated that the probe was able to quantitatively detect hypochlorite in various water samples with good recovery. Significantly, the probe showed extremely low background fluorescence in living cells and was capable of detecting minor variation of endogenous hypochlorite in RAW 264.7cells. Moreover, the fluorescence imaging different concentration of hypochlorite in zebrafish has been successfully conducted. The probe developed herein will be widely used as a reliable tool to accurately monitor the variation of hypochlorite in living organism.

A novel dual functional pyrene-based turn-on fluorescent probe for hypochlorite and copper (II) ion detection and bioimaging applications.

A novel dual-function fluorescent probe PPH was conveniently synthesized by linking pyrazinehydrazide unit and pyrenyl fluorophore. The present probe PPH could be used for simultaneous detection of ClO- and Cu2+ through a fluorescence turn-on response. The probe PPH displayed excellent selectivity and sensitivity towards ClO- and Cu2+ over other anions and metal ions. The detection limits of PPH for ClO- and Cu2+ were calculated to be as low as 4.02nM and 157nM, respectively. The probe PPH had good pH stability and was highly responsive to ClO- and Cu2+ in a wide pH range. Furthermore, this probe could be readily applied to visualize ClO- and Cu2+ on the test paper. Additionally, this probe was successfully utilized to the fluorescence imaging of ClO- and Cu2+ in HeLa cells.

Sensitive and selective fluorescent probe for hypochlorite in 100% aqueous solution and its application for lysosome-targetable cell imaging

A morpholine-functionalized pyrrole-cyanine probe was synthesized via a simple condensation reaction in high yield. This probe exhibits high selectivity toward ClO- on fluorescence and UV-vis spectra in neat aqueous solution. The strong green emission of the probe solution was quenched and the yellow color faded immediately upon the addition of ClO-. The detection limit of the probe for ClO- was 0.165μM. The mechanism of hypochlorite-induced CC breakage was supposed on the basis of EIS-MS, NMR, and density functional theory (DFT) calculation. Finally, the probe was utilized to image ClO- in lysosomes of living cells.

“Turn-On” Fluorescent Probe for Hypochlorite: Successful Bioimaging and Real Application in Tap Water

“Turn-On” Fluorescent Probe for Hypochlorite: Successful Bioimaging and Real Application in Tap Water

Synthesis, fluorescence property and cell imaging of a perylene diimide-based NIR fluorescent probe for hypochlorite with dual-emission fluorescence responses

In this study, for the first time, a novel near-infrared and ratiometric fluorescent probe was conveniently synthesized by reacting PDI-based salicylaldehyde with 2-(hydrazonomethyl)phenol.

A highly sensitive turn-on fluorescent probe for real-time detecting hypochlorite and its application in living cells

It is very necessary to develop real-time, highly sensitive and selective fluorescent probes for hypochlorite (ClO−) in living cells owing to hypochlorite's important role in pathological and physiological processes and its short life. Herein, a pyrene Schiff's base derivative was successfully developed for real-time (within seconds), highly sensitive detecting ClO− with a low detection limit (5.7 nM) and wide pH range (4.0–11.0) based on nucleophilic addition and subsequent hydrolysis mechanism. The probe has aggregation-induced emission properties and emits yellow fluorescence (544 nm) in PBS solution, while it exhibits blue fluorescence in other organic solvents (426 nm (THF) - 460 nm (MeOH)). The probe can be used to response ClO− in A549 cells with low cytotoxicity, a good cell membranes penetration and good biocompatibility. Cell uptake experiment indicates that probe getting into the cells is energy-dependent and is not attributed to endocytosis. Moreover, the probe is successfully used in real water sample to detect ClO− and it can be expected to be applied to ClO− participated biological and pathological functions in biological systems.

Selective and Fast‐Response Fluorescent Probes for Hypochlorite and their Application

It is extremely important to develop selective and sensitive fluorescent probes for the detection of hypochlorite (HClO/ClO−). Herein, two ESIPT‐based fluorescent probes (BS1 and BS2) were designed and prepared for the fast determination of HClO. The probes exhibited excellent specificity towards HClO and showed the rapid and huge fluorescent responses. Moreover, the probes BS1 and BS2 could sensitively detect HClO in the range of 0–100 μM with the low detection limits of 87 and 106 nM, especially. Besides, the success of practical application in water samples and test strips suggested that the synthetic probes may be effective tools for the detection of hypochlorite in environmental samples.

A novel ratiometric and colorimetric fluorescent probe for hypochlorite based on cyanobiphenyl and its applications.

Reported here is a novel ratiometric and colorimetric fluorescent probe 1 for hypochlorite based on cyanobiphenyl and diaminomaleonitrile. This probe 1 was designed based on the mechanism that ClO- selectively cleaved the hydrazone bond (-C=N-) in this probe and released the fluorophore, 3`-formyl-4`-hydroxy-4-biphenylcarbonitrile. The addition of ClO- to the solution of probe 1 resulted in a very large blue-shift in both fluorescence (107 nm) spectra and an obvious fluorescence color change from red to green. Furthermore, this probe displays a rapid response (30 s) and a low detection limit (3.34 × 10-7 M, based on LOD = 3σ/slope) in detecting ClO-. Importantly, practical utility of this probe for the selective detection of ClO- in living cells has been successfully demonstrated, illustrating the great potential for biological analysis. Additionally, the probe 1 was also successfully applied to the detection of ClO- in real water sample.

A fluorescent probe for hypochlorite with colorimetric and fluorometric characteristics and imaging in living cells

An excellent fluorescent probe with “turn on” phenomenon for sensitive monitoring hypochlorite (ClO−) was prepared using the mild condensation reaction between coumarin and hydroxylamine (NH2OH). The probe possessed potent selectivity to ClO− with obvious color changes from yellow to light yellow and green to blue fluorescence emission, which could be noticed by the naked eye. Moreover, the probe has been succeeded in imaging ClO− in living A549 cells and thus has the potential prospect in the visual detection of intracellular ClO−.

Rational Design and Bioimaging Applications of Highly Specific “Turn-On” Fluorescent Probe for Hypochlorite

Hypochlorite (OCl-), an essential part of reactive oxygen species (ROS), plays a crucial role in cellular redox balance. OCl- has been shown to be implicated in many physiological and pathological processes, including liver injury and cancer. Exploitation of fluorescent probes for the OCl- helps to reveal its function in the genesis and progression of the aforementioned diseases. Here we propose an easy-to-fabricate coumarin-based fluorescent probe incorporated with an aryl dihydrazide linker for highly specific detection and biological imaging of OCl- in living cells and tissues. The p-nitrophenyl-modified dihydrazide-linked coumarin derivative (Cou-dhz-Ph-NO2) was screened from a series of candidate molecules and served as a "turn-on" probe with a low background fluorescence interference due to the nitro-group-based quenching on the coumarin fluorescence. The Cou-dhz-Ph-NO2 probe showed high selectivity and fast response with excellent linear relationship for detection of OCl-. A specific OCl--responsive mechanism that the dihydrazide linker could be oxidatively cleaved by OCl- was deduced. The exogenous OCl- and endogenous OCl- were successfully visualized using the Cou-dhz-Ph-NO2 probe in living cells, such as MDA-MB-231 cells, RAW 264.7 cells and neutrophils, and the pathologic tissues, including the tumor tissue and the acutely injured liver tissue. This study paves the way for utilizing the aryl dihydrazide linker as OCl--responsive module, which can aid the evolution of increasingly specific probes for detection of OCl- and diagnosis of OCl--coupled diseases.

A Highly Selective and Sensitive Ratiometric Fluorescent Probe for Hypochlorite and Its Application

A novel water-soluble hybrid fluorescein-coumarin dye(FLNC) fluorescence ratiometric probe to recognize OCl− was designed and synthesized. The most prominent feature of the probe is that the molecular structure contains two different fluorophores, and the fluorescein moiety was connected to coumarin moiety by diacylhydrazine linker. When OCl− was added, the two fluorophores in the FLNC probe could have a rapid respond simultaneously, with high selectivity and sensitivity towards OCl– among other reactive oxygen species/reactive nitrogen species(ROS/RNS) and anions, and the detection limit was measured to be 0.30 μmol/L. In addition, the color changes of the solution could be observed by the naked eye and have a short response time(completed within 1 min), which suggestes that the probe FLNC has the potential to be used for real-time detection.