Thiophenol Concentration Research Articles

Dicyanisophorone-based near-infrared fluorescent probe for the detection of thiophenol and its application in living cells and actual water samples

This article reports a new type of dicyanisophorone-based near-infrared fluorescent probe for the rapid detection of mercaptophenol by introducing 2,4-dinitrobenzene sulfonate group as a specific recognition group for thiophenol. The probe has a significant large Stokes shift (185 nm). At the same time, it exhibits rapid response, high selectivity and high sensitivity to thiophene. In addition, the fluorescence of the probe at 650 nm has a good linear relationship with the concentration of thiophenol in the range of 0–100 μM, and the detection limit is as low as 65 nM. The probe has been successfully applied to the detection of thiophenol in actual water samples, and has good live cell imaging effects, and at the same time shows the superiority of its low cell toxicity.

Rational design of a new near-infrared fluorophore and apply to the detection and imaging study of cysteine and thiophenol

The development of a near-infrared fluorophore with excellent fluorescence performance, a large Stokes shift, and good biocompatibility has become a focus in the field of fluorescence imaging in recent years. Based on quantum chemistry calculations and reasonable molecular design strategies, a new NIR fluorophore was developed and characterized by simple synthesis, easy structural modification, and a large Stokes shift (105 nm). Furthermore, two new "activatable" fluorescent probes QN-Cys and QN-DNP were synthesized using a simple structural modification. The probe QN-Cys can recognize Cys with high sensitivity (LOD = 128 nM) and high selectivity, and its fluorescence intensity has a good linear relationship with the Cys concentration in the range of 5–35 μM. Furthermore, probe QN-Cys can effectively distinguish Cys from Hcy and GSH, and was successfully applied to the detection and imaging of Cys in human serum, cells, and zebrafish. The probe QN-DNP showed a good specific and sensitive (LOD = 78 nM) fluorescence response to thiophenol, and its fluorescence intensity has a good linear relationship with the thiophenol concentration in the range of 5–30 μM. Furthermore, it was successfully applied to detect thiophenol in real water samples with good recoveries (97–102%), and image thiophenol in living cells, zebrafish and mice. Notebly, the QN-DNP probe could be applied to visualize the distribution of thiophenol in the mice.

Simple NIR-Emitting ESIPT Fluorescent Probe for Thiophenol with a Remarkable Stokes Shift and Its Application.

Thiophenol as a highly toxic compound can harm the environment and living organisms and thus demands effective detection. In this work, we presented a near-infrared fluorescent probe (DAPH-DNP) for detecting thiophenol according to the ESIPT mechanism using 2,4-dinitrophenyl group as a recognition unit. This probe displayed specificity toward thiophenol over other related analytes. Meanwhile, there was good linearity between the relative fluorescence intensity of DAPH-DNP and the concentration of thiophenol in the range of 0–80 μM. This probe also showed a low detection limit of 3.8 × 10–8 and a marked Stokes shift (192 nm). Further, this probe could be used for monitoring thiophenol in environmental water samples and imaging thiophenol in living cells, which indicated that this probe had a real application in the environment and living organisms.

Merocyanine-based turn-on fluorescent probe for the sensitive and selective determination of thiophenols via a pKa shift mechanism

The development of fluorescent probes for the sensitive and selective determination of highly toxic thiophenols is considerably important in the fields of biological and environmental sciences. Herein, a turn-on fluorescent probe for thiophenol, named MCSH, was constructed based on a pKa shift mechanism, employing merocyanine dye as the fluorophore and 2,-4-dinitrobenzenesulfonamide (DNBS) group as the recognition unit. The imine nitrogen of MCSH has a pKa value of 4.12, which renders its non-fluorescent Schiff base form exclusively under neutral conditions. However, after reacting with thiophenols, its DNBS group was removed to afford a merocyanine dye as the final product, whose pKa value upshifts to 8.11, and was present mainly as the fluorescent protonated Schiff base form under neutral media. Such drastic change in pKa values leads to a significant fluorescence enhancement and can be utilized for the detection of thiophenols. The fluorescence intensity at 627 nm increases linearly with thiophenol concentration in the range of 0.2–3 μM with a detection limit of 15 nM (S/N = 3). MCSH displays high selectivity for the detection of thiophenols over a wide range of other analytes, including aliphatic thiols. Furthermore, the preliminary applications of MCSH for monitoring thiophenols in living cells and environmental have been carried out.

A ratiometric fluorescent probe for visualization of thiophenol and its applications.

Thiophenol has a broad application in agriculture and industry. However, thiophenol can harm to the environment and health for its high toxicity. Developing an effective method for detection of thiophenol in the field of environmental and biology is valuable. In this work, we construct a reaction-based ratiometric fluorescent probe (E)-4-(2-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)vinyl)-1-(4-(2,4-dinitrophenoxy)benzyl)pyridin-1-ium bromide (DCVP-DNP) for probing thiophenol in environment and cells by employing (E)-7-(diethylamino)-3-(2-(pyridin-4-yl)vinyl)-2H-chromen-2-one (DCVP) as the fluorophore and 2,4-dinitrophenyl (DNP) ether as the recognition group for the first time. The probe has high selectivity for thiophenol though thiophenol-triggered nucleophilic substitution reaction. In addition, the ratio of emission intensities of the probe has linearly with thiophenol concentration in the range of 0-65μM and the detection limit of thiophenol is as low as 4.8×10-8M. Moreover, the probe can not only be applied for detection of thiophenol in water samples, but also image thiophenol in living cells, suggesting its potential application in environment and biological system.

A dual-response near-infrared fluorescent probe for rapid detecting thiophenol and its application in water samples and bio-imaging

Thiophenol is widely known as a highly toxic substance that can cause serious harm to the environment and health. Rapid and non-destructive detection of thiophenol is of great significance for environmental management. In this work, we designed and synthesized a near-infrared (NIR) fluorescent probe, (E)−4-(2-(4-(dicyanomethylene)−4H-chromen-2-yl)vinyl)−2-formylphenyl-2,4-dinitrobenzenesulfonate (DCM-CHO-D), that can respond to thiophenol rapidly (less than 3 min) based on intramolecular charge transfer (ICT) mechanism. DCM-CHO-D has high selectivity and sensitivity to the detection of thiophenol. And there is a linear relationship between the fluorescence intensity of DCM-CHO-D and thiophenol concentration in the range of 0–10 μM, the limit of detection (LOD) is as low as 0.22 μM. What′s more, DCM-CHO-D can not only be used as an ideal colorimetric tool for detecting thiophenol in water samples, but also image thiophenol in living cells, indicating its potential utility for thiophenol sensing in environmental and biological samples.

A dicyanoisophorone-based near-infrared fluorescent probe and its application for detecting thiophenols in water and living cells

We report herein a new dicyanoisophorone-based colorimetric and near-infrared (NIR) fluorescent probe for rapid detection of thiophenols. This probe possesses a remarkable large Stokes shift (208 nm) and works in almost pure aqueous solution under mild conditions. More importantly, it displays a rapid, highly selective and sensitive dual colorimetric and NIR fluorescent turn-on signal responses for thiophenols and allows the detection of thiophenols in the presence of analytes including amino acids, biothiols and aliphatic thiols. Moreover, the fluorescence of this probe at 655 nm displays a good linear relationship with the thiophenol concentration ranging from 0 to 20 μM, and the detection limit is as low as 12 nM. Furthermore, the practicability of this new probe has been successfully proved by detection of thiophenol in real water samples and bioimaging of thiophenol in living cells.

A colorimetric and turn-on NIR fluorescent probe based on xanthene system for sensitive detection of thiophenol and its application in bioimaging

Developing fluorescent probes for specific detection of extremely toxic thiophenols is pretty significant in the field of environment, chemistry and biology. We report herein a turn-on red fluorescent xanthene-based probe (RD-Probe) for detecting thiophenol with high selectivity over other analytes including aliphatic thiols. The probe could play the part of a “naked-eye”colorimetric indicator toward thiophenol. Moreover, the relative fluorescence intensity at 653 nm displayed good linearity with the concentration of thiophenol ranging from 0 to 6 μM, and the limit of detection for thiophenol could be as low as 15 nM. Furthermore, the practicability of RD-Probe has been successfully proved through the quantitative thiophenol detection in real water samples and fluorescence bioimaging of thiophenol in HeLa cells.

A BODIPY‐based Fluorescent Probe for Thiophenol

Thiophenol has been listed as one of the main sources of pollution. Sensitive probes for thiophenol are very significant. Herein, a BODIPY‐based fluorescent probe, named BDP, for poisonous thiophenol detection has been reported. BDP shows rapid response (15 s) and clear fluorescence enhancement (30 folds) to thiophenol in solution. The intensity of fluorescence and concentration of thiophenol have a good linear relationship. The detection limit is as low as 13.6 nmol · L−1. BDP is stable towards pH and light radiation. Cell experiments demonstrate that BDP has good cell membrane penetrability, low cell toxicity and excellent imaging properties in living cells. Therefore, BDP has significant value on the detection of thiophenol in solution and in living cell.

Probing Thiophenol Pollutant in Solutions and Cells with BODIPY-Based Fluorescent Probe

Thiophenol is extensively used in the manufacture of industry and agriculture. However, the high concentration of thiophenol will cause damage to living organisms and environment pollution. Herein, a BODIPY-based fluorescent probe has been designed and synthesized for probing thiophenol pollutant in solutions and cells. It shows high selectivity and a turn-on effect. Cell experiments demonstrate that the probe has low cell toxicity, good and rapid cell membrane penetrability, and excellent imaging properties in living cells. The real water samples can be detected directly by fluorescent assay or test strips made from the probe. Therefore, the probe has important value on the detection of thiophenol in the environment and industrial production.

Scattering Correlation Spectroscopy and Raman Spectroscopy of Thiophenol on Gold Nanoparticles: Comparative Study between Nanospheres and Nanourchins

The surface characterization of branched and spherical gold nanoparticles was done by two complementary techniques: scattering correlation spectroscopy (SCS) and surface-enhanced Raman spectroscopy (SERS). Thiophenol was used as a surface marker to probe the surface area and the gold–thiophenol interaction in gold nanourchins (GNUs) and gold nanospheres (GNSs). We observed that, for GNU, the thiophenol is first grafted on the core, with a saturation concentration of about 10–3 M as observed for GNSs. Afterward, the saturation of the branches occurs at a higher thiophenol concentration (∼1 M). A numerical calculation of the surface areas of GNSs of different sizes allowed for the estimation of the GNU surface area. The hydrodynamic radius was measured at different steps of thiophenol–GNP functionalization. By comparing spherical and nonspherical nanoparticles, we demonstrate that the molecule–GNP interaction is highly dependent on the nanoparticle morphology (size and shape).

Kinetics and mechanism of the chain reaction of N,N′-diphenyl-1,4-benzoquinone diimine with thiophenol in chlorobenzene

The regularities of the reaction of N,N′-diphenyl-1,4-benzoquinone diimine with thiophenol in chlorobenzene at 343 K were studied by kinetic spectrophotometry. The reaction orders were determined for the components under the conditions when the concentration of thiophenol considerably exceeded that of quinone diimine: nQDI = 1.5 for quinone diimine and nPhSH = 1.0 for thiophenol. The initiators (azo-bis-isobutyronitrile and tetraphenylhydrazine) were found to considerably accelerate the reaction, which suggests that the reaction proceeded by the chain mechanism. The reaction chain length changed from one dozen to several dozens of units depending on the experimental conditions. The chain mechanism (kinetic scheme) of the reaction was suggested; it agrees with the experimental data, according to which the chains are initiated simultaneously by the second and third order reactions between quinone diimine and thiophenol. The rate constants of these stages at 343 K were determined: kbi = 0.014 ± 0.002 L mol−1s−1; ktri = 22.8 ± 1.8 L2 mol−2s−1. The limiting stage of chain propagation was concluded to be the reaction of the thiyl radical with quinone diimine; the rate constant of this stage was evaluated: kpr ∼ 1.3 × 106 L mol−1 s−1 at 343 K.

Chain mechanism of the reactions of N,N′-diphenyl-1,4-benzoquinone diimine with thiophenol and 1-decanethiol

The kinetics of the reactions of N,N′-diphenyl-1,4-benzoquinone diimine with thiophenol and 1-decanethiol in chlorobenzene at 343 K has been investigated spectrophotometrically in an argon atmosphere with monitoring of the disappearance of quinone diimine as its absorbance in the visible range. The acceleration of the reactions in the presence of initiators—tetraphenylhydrazine and azobisisobutyronitrile—indicates that the reactions proceed via a chain mechanism under the chosen experimental conditions. The chain length of the reactions in the absence of an initiator is estimated: ν ≈ 10 units in the reaction of quinone diimine with thiophenol and ν ≈ 100 units in the reaction with 1-decanethiol at a quinone diimine concentration of about 10−4 mol/L and thiol concentrations of about 10−3 mol/L. The dependence of the kinetic parameters of the initiated reaction on the thiophenol concentration suggests that the reaction of the thiyl radical with quinone diimine is the rate-determining step of chain propagation. The rate constant of this reaction is estimated at k pr = 3.2 × 105 L mol−1 s−1. The rates of chain initiation due to the direct interaction of the initial reactants are estimated. In these reactions, the homolytic cleavage of the S-H bond occurs in the thiol, due to which, other conditions being equal, the radical formation rate in the quinone diiminethiophenol system is at least two orders of magnitude higher than that in the quinone diimine-1-decanethiol, in which the strength of S-H bond is higher. A radical chain mechanism is proposed for the reaction of quinone diimine with the thiols on the basis of the data obtained.

The role of thiophenol in the proposed mechanism for one pot transformation of 2-phenylthio-3-aminocyclohexanols to dehydropiperidine derivatives

This paper describes the effect of thiophenol concentration on photochemical rearrangement of 2-phenylthio-3-aminocyclohexanols to the corresponding protected aminoaldehydes. The obtained aminoaldehyde is in equilibrium with its corresponding deoxyazasugar. The latter could be converted to the corresponding dehydropiperidine with a good yield in the same reaction media by controlling the thiophenol concentration. Also a proposed mechanism for this one pot transformation is reported.

A Comparative Study of Gold Nanocubes, Octahedra, and Rhombic Dodecahedra as Highly Sensitive SERS Substrates

Gold nanocubes, octahedra, and rhombic dodecahedra with roughly two sets of particle sizes have been successfully synthesized via a seed-mediated growth approach. All six samples were analyzed for comparative surface-enhanced Raman scattering (SERS) activity. All of these Au nanostructures were found to yield strong enhancement at a thiophenol concentration of 10(-7) M and are excellent SERS substrates. Rhombic dodecahedra with a rhombus edge length of 32 nm showed significantly better enhancement than the other samples and can reach a detection limit of 10(-8) M. Simulations of the binding energies of thiophenol on the different faces of gold and electric near-field intensities of these nanocrystals have been performed to evaluate the experimental results. Superior SERS activity of these nanocrystals can be expected toward the detection of many other molecules.

Some anomalies in the kinetics of heterogeneous oxidative condensation reactions

AbstractThe rate of thiophenol oxidation in a catalysed gas‐liquid reaction is found to depend on the initial concentration of thiophenol but is independent of the changes in thiophenol concentration which occur during the course of the oxidation. The reaction rates have been used to construct a Lineweaver‐Burk plot. These results are compared with those which have previously been obtained in the oxidative condensation of 2,6‐dimethylphenol. The kinetic similarities between catalysed oxidative condensation reactions and enzyme reactions are discussed. It is shown that the linearity of the Lineweaver‐Burk plots does not ensure that the absorption of oxygen is chemically controlled. It is suggested that deductions which previous workers have made from the use of Lineweaver‐Burk plots must be treated with caution.

Radiolysis of polyisobutene IV: A study of the role of free radicals in the fracture reaction using radioactive additives

The influence of additives on the formation of polymer radicals and macromolecular fractures in polyisobutene by exposure to 4 MeV electrons has been studied using phenyl- 3 H- sec-butyl- 35 S 1-disulphide, thiophenol- 3 H, thiophenol- 35 S, and nitrobenzene- 14 C. G (polymer radicals) was found to decrease from a maximum value of 7·3 at a concentration of thiophenol of 3 to 5 × 10 −4 mole/g to 4·5 to 5·4 at about 15 × 10 −4 mole/g and then to remain constant. As this decrease may be due partly to the scavenging of H · and CH 3 · precursors, it is supposed that the primary polymer radicals are formed by processes which are relatively insensitive to the presence of large concentrations of a ‘protective agent’. Comparison of the effects of thiophenol on yields of radicals and fractures leads to the conclusion that two types of primary polymer radical are formed. One is due to the fracture of CH and CCH 3 bonds, 4·2 ⩾ G(—) ⩾2.7, and the other to direct fracture of the main chain of carbon atoms, G(—·) ⩾ 3·1. Nitrobenzene- 14 C, which is only slightly soluble, combines with the polymer, G (combined nitrobenzene) = 1·2, and increases the G (fractures) value by 0·6 after a dose of 5 Mrad. An explanation is suggested for the contrasting effects of thiophenol and nitrobenzene at low concentrations. Thiophenol reduces the yield of fractures by stabilizing the radical — and preventing β-bond scission. Nitrobenzene fails to do this but instead further increases the yield of fractures by preventing the ‘fracture-offsetting’ combination of the radicals, —·, formed by β-bond scission of —.

The Radiation-induced Reactions of Benzene with Sulfur and Sulfur Compounds

Abstract The irradiation of a benzene solution of sulfur gave thiophenol, diphenyl disulfide, diphenyl sulfide, hydrogen sulfide, hydrogen and some polymers. The formation of thiophenol and of hydrogen sulfide is considered to be initiated by the radiolysis of benzene, which gives phenyl and hydrogen radicals, which in turn combine with sulfur in succeeding steps. However, the thiophenol formed is oxidized to the disulfide as the radiation energy absorbed in benzene transfers to thiophenol. The effect of the initial concentration of thiophenol and of the radiation dose has been measured. The relative stability of the S–H and C–S bond for radiation was about 1:200. The radiolysis of diphenyl disulfide or hydrogen sulfide in benzene were found to form thiophenol. In a kinetical study of the decomposition of thiophenol in benzene, 0.7 benzene molecule is excited by the 100 eV. of gamma rays absorbed, while the ratio between the energy transfer to thiophenol from excited benzene and the deactivation of excited benzene itself is about 100 to 1.