Search

SO2 plays an important role in our life and is also associated with many diseases, so it is a double-edged sword. Therefore, it is necessary to develop a probe for detecting sulfur dioxide derivatives. Herein, on account of the Michael addition reaction mechanism, a near-infrared (NIR) fluorescent probe, HBQI, toward sulfur dioxide derivatives was developed, and the probe has high selectivity and strong anti-interference ability. The application study indicates that probe HBQI can detect sulfur dioxide derivatives in real water samples with good recovery. In addition, HBQI has been applied to live-cell imaging through confocal fluorescence techniques. [ABSTRACT FROM AUTHOR]

A Near-Infrared (NIR) ratiometric and on-off fluorescent probe 1 was synthesized, which exhibited high sensitivity and excellent selectivity in arginine (Arg) recognition. 1 can quantitatively detect Arg in concentration range from 0 to 150 μM with the LOD of 138 nM. Further, it displayed excellent selectivity and anti-interference over many biological species, metal ions and anions. Due to its ability to target lysosome, the response of Arg to this probe in a living cell was successfully tracked in a ratiometric manner via fluorescence imaging. [ABSTRACT FROM AUTHOR]

Based on 8-hydroxyquinoline, a 1,8-naphthalimide-derived colorimetric and fluorescent probe was synthesized for naked-eye and fluorescent recognition of F − (from both tetrabutylammonium fluoride and NaF) with high sensitivity and excellent selectivity. The probe can be employed to detect F − quantitatively within certain concentration range, and the detection limit could be as low as 1.8 μM for tetrabutylammonium fluoride and 9 μM for NaF. With this probe, the tests for fluorine contents in tap water, water sample from Eyebrow Lake and several brands of toothpastes were successfully performed. [ABSTRACT FROM AUTHOR]

Abstract: Based on Rhodamine B, two Al3+/Cu2+-selective chemosensors were synthesized, which display a high selectivity for Al3+ and Cu2+ among environmentally and biologically relevant metal ions. A 1,8-Naphthyridine modified rhodamine derivative can detect Al3+ in ethanol with off–on fluorescence behavior, and detect Cu2+ in aqueous solution with colorimetric method. The 8-Hydroxyquinoline-based rhodamine sensor can detect Al3+ in ethanol with both off–on fluorescence and colorimetric methods. The detection mechanism involves a ring-opening process as a consequence of metal complex formation. Job's plots and a time-of-flight mass spectral study indicated that each chemosensor chelated Al3+/Cu2+ with 1:1 stoichiometry. The binding of the chemosensors and Al3+/Cu2+ is chemically reversible by the addition of F−/EDTA solution, respectively. [Copyright &y& Elsevier]

A pyrene derivative has been synthesized as a visible light excitable fluorescent chemodosimeter which exhibits “on–off” and “green–red” fluorescence behavior for Ni2+ and Pb2+ with different reaction speed, respectively, and its sensing ability toward metal cations and counter ions was investigated in detail. The high selectivity of the ‘in situ’ prepared Ni2+ and Pb2+ complexes toward EDA and the reaction speed difference provide two new effective methods for distinguishing between Ni2+ and Pb2+. [ABSTRACT FROM AUTHOR]

A pyrene derivative has been synthesized as a visible light excitable fluorescent chemodosimeter which exhibits “on–off” and “green–red” fluorescence behavior for Ni2+ and Pb2+ with different reaction speed, respectively, and its sensing ability toward metal cations and counter ions was investigated in detail. The high selectivity of the ‘in situ’ prepared Ni2+ and Pb2+ complexes toward EDA and the reaction speed difference provide two new effective methods for distinguishing between Ni2+ and Pb2+. [ABSTRACT FROM AUTHOR]

A highly sensitive and selective 1,8-naphthyridine-based fluorescent chemodosimeter for Zn2+has been designed, synthesized, and applied to the detection of intracellular Zn2+. [ABSTRACT FROM AUTHOR]

It is critical to develop probes for rapid, selective, and sensitive detection of the highly toxic hydrazine in both environmental and biological science. In this work, under mild condition, a novel colorimetric and off-on fluorescent probe was synthesized for rapid recognition of hydrazine with excellent selectivity over other various species including some biological species, metal ions and anions. The limit of quantification (LOQ) value was 1.5 × 10 − 4 M–3.2 × 10 − 3 M (colorimetric method) and 1.5 × 10 − 4 M − 3.2 × 10 − 3 M (fluorescent method) with as low as detection limit of 46.2 μM. [ABSTRACT FROM AUTHOR]

Inflammation is an innate defense response of an organism to tissue damage which is accompanied by biological processes such as depolarization, autophagy, and endogenous bisulfite production. As a novel type of iron-dependent programmed apoptosis, ferroptosis accumulates an excessive lipid peroxide, leading to fluctuations of polarity and SO 2. To study the dynamic correlation between SO 2 and polarity of these two diseases is of great significance for revealing the precise regulation mechanism of inflammation and ferroptosis. In this research, a multicolor fluorescent probe BDMOB was developed by coupling a sulfur dioxide response site with push-pull electrons, realizing orange and near-infrared fluorescence emission, allowing to the simultaneous detection of polarity and SO 2. With its attractive AIE and NIR properties, BDMOB is able to effectively prevent background interference and effectively solve the problem of fluorescence quenching. For the first time, the slight fluctuations in SO 2 and polarity during inflammation and ferroptosis is shown by examining parameter changes during aberrant processes at the in vivo and in vitro levels. This offers fresh insights into the diagnosis and therapy of disease processes. [Display omitted] • Three-channel independent visualization of SO 2 and polarity fluctuations was recorded by BDMOB. • The therapeutic process of inflammation and ferroptosis is examined by fluorescence. • Endogenous and exogenous SO 2 derivatives can be sensitively monitored by BDMOB. • The application of discriminating cancer cells from normal ones was discussed. [ABSTRACT FROM AUTHOR]

As a pivotal parameter of microenvironment, viscosity is closely related to many diseases and dysfunction in vivo. Lipid droplets, as organelles that store and metabolize lipids, are involved in various physiological processes related to metabolism in cells. Diabetes is one of the metabolic diseases that may lead to dysfunction of organs, which is associated with abnormal viscosity changes. It is of great significance for the study of related diseases to clarify the relationship between viscosity variations in vivo and monitor the changes of lipid droplets. Here, a near-infrared fluorescent probe DPX ((E)− 6-(dimethylamino)− 4-(4-(diphenylamino)benzylidene)− 9-methyl-1,2,3,4-tetrahydroxanthylium) with AIE characteristics was designed, which shows an "off-on" fluorescence response to viscosity based on twisting intramolecular charge transfer (TICT) mechanism. The probe DPX features excellent mitochondria and lipid droplets targeting, and sensitively monitor accumulation of LDs induced by oleic acid and mitochondrial viscosity variations in HeLa cells. More importantly, DPX has been successfully applied to visualize viscosity changes of diabetic liver injury in vivo, which may be benefit for development of diabetes related clinical research. [Display omitted] • Based on its AIE and near-infrared emission (725 nm), noninvasive bio-imaging was achieved. • DPX can monitor the accumulation of lipids and variations of mitochondrial viscosity. • DPX can unequivocally discriminate the injured liver from the normal liver. • It is a LDs-targeting NIR fluorescent probe for mitochondrial viscosity and diabetic mice. [ABSTRACT FROM AUTHOR]

The polarity and viscosity of the microenvironment are associated with the control of the onset and progression of pathological diseases, including inflammation, immuno-suppression and cancer. If appropriate treatment is neglected, alcoholic acute liver injury (AALI), the initial sign of alcoholic liver diseases, may transform into hepatic lesions. Therefore, it's crucial to create a particular probe to detect AALI swiftly and track its progression. Herein a polarity and viscosity dual-responsive crimson fluorescent probe (PPBI) was designed and developed, which can target mitochondria and lipid droplets. PPBI possesses aggregation-induced emission properties, good photostability and strong anti-interference ability against pH, metal ions, anions and biomolecules. This probe can distinguish cancer cells from normal ones using changes of green and red fluorescence, as well as identify changes in the cellular microenvironment associated with inflammatory and ferroptosis processes. In addition, changes in polarity and viscosity can be amplified by in vivo imaging in a mouse model to monitor alcohol-induced acute liver injury and to effectively detect the course of pharmacological intervention therapy. All the results suggest that PPBI could be a promising real-time fluorescence imaging tool for diagnosis and treatment of acute alcoholic liver injury. [Display omitted] [ABSTRACT FROM AUTHOR]

As a signal molecule, SO 2 plays an important role in the process of cell metabolism. The abnormal level of sulfur dioxide will induce many diseases of human body. Viscosity is an important index of lysosome. Abnormal lysosome viscosity can also lead to many diseases. Therefore, we have developed a new fluorescence probe PAPD for simultaneous imaging of sulfur dioxide derivatives and lysosomal viscosity. The probe realizes rapid detection of HSO 3 − based on Michael addition reaction mechanism. At the same time, with the increase of viscosity, intramolecular rotation is inhibited, thus the probe shows sensitive fluorescence enhancement. In addition, the results of the co-localization experiments show that PAPD has good lysosomal targeting ability. Further studies show that PAPD can be used as a dual-responsive fluorescence probe for SO 2 and viscosity in lysosomes. PAPD can monitor the changes of sulfur dioxide derivatives and viscosity sensitively at the same time, and can well locate in lysosomes. [Display omitted] • A NIR fluorescent probe PAPD was developed for detecting the SO 2 derivatives and viscosity in lysosomes. • PAPD towards HSO 3 − represented excellent selectivity, anti-interference, photostability, and thermal stability. • PAPD was applied for sensing viscosity, endogenous and exogenous HSO 3 − in cells. [ABSTRACT FROM AUTHOR]

It is crucial to develop highly sensitive and selective probes toward hydrazine because it is a class of highly toxic and pollutant compound. Herein, using fracture of carbon carbon double bond and dissociation of amide by hydrazine, a novel off-on fluorescent probe was developed for hydrazine. The probe can quantitatively detect hydrazine in concentration range from 0 to 20 μM with the LOD of 140 nM. Further, it displayed excellent selectivity and anti-interference ability over many neutral molecules, metal ions, anions, and biological species. The ability to target lysosome and the response of hydrazine to this probe in a living cell was successfully tracked via fluorescence imaging. [ABSTRACT FROM AUTHOR]

Abnormal SO 2 derivatives level induces mitochondrial and lysosomal dysfunction, which is associated with a variety of diseases. Therefore, it is imperative to develop fluorescent probes which are suitable for detection of SO 2 derivatives in biological systems. Herein, we developed two new ratiometric fluorescent probes, MByn and HByn, which can respond to HSO 3 − in PBS buffer solution accurately and rapidly on basis of Michael addition reaction. After addition of HSO 3 −, ratiometric response signal increases by 5 folds, accompanied by a macroscopic change of fluorescence color. What's more, the two novel fluorescent probes MByn and HByn exhibited low detection limit (LOD = 0.96/0.79 μM), good photostability and low cytotoxicity. Cell imaging experiments showed that MByn and HByn were able to localize mitochondria and lysosomes accurately and detect both exogenous and endogenous SO 2 derivatives in living cells. [Display omitted] • Beyond fluorescence ratio changed of the probes toward addition of HSO 3 − (0−20.0 μM). • The probes showed relatively high fluorescence quantum yields. • Two probes can achieve dual targeting of mitochondria and lysosomes. • The probes could be used to monitor exogenous and endogenous HSO 3 − . [ABSTRACT FROM AUTHOR]

It is significant to develop probes for rapid, selective, and sensitive detection of the highly toxic hydrazine in both environmental and biological science. In this work, under mild condition, a novel colorimetric and ratiometric fluorescent probe ( probe 1 ) was synthesized. Probe 1 with a chemoselective reaction mediated by hydrazine in which the diethyl malonate moiety was transformed into an aldehyde group exhibited high sensitivity and good selectivity in hydrazine recognition. Probe 1 can quantitatively detect hydrazine in concentration range from 0 to 120 μM with the LOD of 1.6 μM. Further, it displayed good selectivity and anti-interference over many species including some nucleophilic species, anions and metal ions. The ratiometric fluorescence change of this probe upon addition of hydrazine in living cells has been successfully demonstrated. Furthermore, the probe displays low dark toxicity under physiological temperature. [ABSTRACT FROM AUTHOR]

The probes could simultaneously target four kinds of organelles, and the four probes could also track mitochondria with no dependence of membrane potential. [Display omitted] • Four multiple organelle-targeted fluorescent probes were developed to image viscosity. • The four probes could track mitochondria with no dependence of membrane potential. • The probes could detect viscosity changes in lyso and mito. Organelles, including mitochondria (mito), lysosomes (lyso), endoplasmic reticulum (ER), Golgi apparatus (Golgi), and ribosome et al., play a vital role in maintaining the regular work of the cell. Viscosity is an essential parameter in the cellular microenvironment. Herein, four viscosity-sensitive near-infrared fluorescent probes DMPC, DEPC, DHDM and DHDV that can simultaneously target multiple organelles were synthesized. As the viscosity increased, the fluorescence intensity of the probes gradually increased due to the hindrance of the rotation of the carbon-carbon single bond. The fluorescence intensity of DHDV increased by about 453 times, and the fluorescence quantum yield also increased from 0.051 to 0.681. Cell experiments indicated the probes could simultaneously target four kinds of organelles, and the four probes could also track mitochondria with no dependence on membrane potential. Further experiments showed that the probes could detect viscosity changes in lyso and mito. In addition, the probes also demonstrated the advantages of low cytotoxicity, good anti-interference and stability, providing a simple and effective tool for studying the activity of organelles with changing viscosity signals. [ABSTRACT FROM AUTHOR]

Viscosity is an important microenvironmental indicator that plays an important role in the process of information transmission in various regions. Herein, two coumarin-based viscosity-sensitive fluorescent probes (CHB, CHN) were synthesized and the photophysical properties of the two probes were studied. The fluorescence quantum yields of CHB and CHN in glycerol can be as high as 25.2% and 18.3% respectively. The two probes can linearly detect viscosity in the viscosity logarithm range of 0.83–2.07, which is not interfered with pH, metal ions, anions and biomolecules. Fluorescent confocal cell experiments show CHB and CHN have good targeting ability to mitochondrion, lysosome, Endoplasmic reticulum and Golgi apparatus, and can be used to detect viscosity in mitochondrion/lysosome. Two probes synthesized from coumarin derivatives and conjugated hemicyanine were rationally constructed for detection and imaging of intracellular mitochondrial/lysozyme viscosity in living cells. [Display omitted] • Two NIR viscosity responsive fluorescent probes were synthesized. • The probe can track mitochondria independently of membrane potential. • Two probes can target viscosity in both mitochondria and lysosomes. [ABSTRACT FROM AUTHOR]

A dual-model fluorescent probe for formaldehyde has been developed. With excitation at 365 and 400 nm respectively and upon addition of formaldehyde, the fluorescent probe displays off-on fluorescence responses at 415 and 505 nm. Formaldehyde can be detected quantitatively in the concentration range from 0 to 2.7 × 10 −2 M and the detection limit on fluorescence response of the probe can be as low as 6 μM. The proposed method was successfully employed for preliminary application in several commercially available foods. [ABSTRACT FROM AUTHOR]

Abstract: A series of isomers were synthesized and identified, two isomers of which were developed as the dual-channel fluorescent probe toward Cd2+. BF2 dissociates from the probe upon reaction with CdCl2, demonstrating a new approach for sensing Cd2+. [Copyright &y& Elsevier]

Starting from 4-bromonaphthalene-1-carbonitrile, three uncomplicated but efficient HSO 3 − sensitive ratiometric fluorescent probes HNIC, CIVP and HVIC were designed and synthesized through ICT mechanism and the Michael-type addition reaction. The probes can image HSO 3 − in living cells. The probes not only have good fluorescence stability and strong anti-interference ability, but also display mitochondrial targeting ability. [Display omitted] • The probes detect HSO 3 − through ICT and the Michael-type addition reaction. • The probes exhibit ratiometric and off–on fluorescence changes towards HSO 3 −. • The probes show good selectivity and strong anti-interference ability. • The probes achieve targeting of mitochondria. Sulfur dioxide (SO 2) is an environmental pollutant in the atmosphere which is easily absorbed by the human body. After being inhaled in the body, SO 2 is quickly converted into bisulfite (HSO 3 −), forming a balance in which SO 2 and HSO 3 − coexist in the body status. A large number of epidemiological studies have shown that abnormal levels of sulfite and bisulfite are related to the appearance of numerous diseases such as atherosclerosis, essential hypertension, and lung tissue fibrosis. Therefore, it is essential to develop an effective method to detect bisulfite. In this work, starting from 4-bromonaphthalene-1-carbonitrile, three uncomplicated but efficient HSO 3 − sensitive ratiometric fluorescent probes HNIC, CIVP and HVIC were designed and synthesized through ICT mechanism and the Michael-type addition reaction. The probes can image HSO 3 − in living cells. The probes not only have good fluorescence stability and strong anti-interference ability, but also display mitochondrial targeting ability. [ABSTRACT FROM AUTHOR]

SO 2 and its derivatives (HSO 3 −, SO 3 2−) play a significant important role in many industries and organisms. Based on coumarin and benzopyranose, a promising NIR ratiometric fluorescent probe BAOA (11-oxo-2,2′,3,3′,6,7,7′,8′-octahydro -1H,1′H,5H,6′H,11H- [10,12′-bipyrano [2,3-f] pyrido [3,2,1-ij] quinolin]-13′-ium perchlorate) was designed and developed to detect HSO 3 − rapidly and sensitively. The sensing mechanism was Michael addition reaction, in which, strongly nucleophilic HSO 3 − attacked carbon-carbon double bonds and BAOA-HSO 3 was formed. A superior linear calibration curve between the fluorescence ratio I 490 /I 722 and concentrations of HSO 3 − was obtained in the range of 1.25–8.75 μmol/L and the LOD was figured out as 63.0 nmol/L. Cell experiments showed that BAOA could not only locate mitochondria, lysosomes, ER and Golgi but also detect exogenous HSO 3 − in living cells. A promising NIR ratiometric fluorescent probe for HSO 3 − was designed, which sensing mechanism was nucleophilic HSO 3 − attacking carbon-carbon double bonds resulting from Michael addition reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

Solvents exhibit different color reactions via regulation of the structure, kinetics, and charge distribution of organic compound molecules. In recent years, solvatochromic probes have good application prospects in the fields of chemistry and biology. In this work, we synthesized three fluorescent probes (PBIC–C, PAIC-C, PPIC-C) sensitive to solvent polarity. We have studied the photophysical properties (spectra, quantum yield, and fluorescence lifetime under different solvents) of these probes. The isomerization nature was verified by nuclear magnetic titration. In order to further confirm our guess, we also performed theoretical calculations, and the results were roughly the same as the experimental results. In addition, cell imaging tests revealed that the designed probes could be used as dual intracellular mitochondria/lysosome-targeting fluorescent probes for biological applications. [Display omitted] • The probes exhibit sharp color changes in different polar solvents. • The probes show relatively high fluorescence quantum yields. • The probes achieve dual targeting of mitochondrials and lysosomes. [ABSTRACT FROM AUTHOR]

As momentous reactive oxygen species (ROS), it is necessary to develop high-sensitivity and high-specificity fluorescent probes for tracking hypochlorite anion (ClO−) in environmental and biological systems. Herein, a kind of red luminescent carbon dots (NS-dots) was synthesized by one-step solvothermal method to detect ClO− in PBS buffer solution (V PBS :V EtOH = 100:1, pH = 7.4). The NS-dots has high sensitivity and low detection limit (13.3 μmol/L) for detecting ClO− with linear range from 6.7 × 10−5 mol/L to 26.7 × 10−5 mol/L. Using Rhodamine B (31% at 520 nm in water) as a reference, the NS-dots have a fluorescence quantum yield of 7.2%. Intracellular photostability, mitochondrial targeting properties and the fluorescence imaging towards intracellular ClO− were demonstrated. A high-sensitivity and high-specificity red luminescent carbon dots was synthesized by one-step solvothermal method to detect ClO− in PBS buffer solution. Unlabelled Image • The NS-dots exhibits excellent water solubility and photostability. • The as-prepared NS-dots exhibit high sensitivity towards ClO−. • The NS-dots show low detection limit and a wide range of pH applications. • NS-dots can be used for cell imaging and mitochondrial localization. [ABSTRACT FROM AUTHOR]