Selective Detection Of Sulfite Research Articles

A combination of experimental and TD-DFT investigations on the fluorescent detection of sulfite and bisulfite ions in aqueous solution via nucleophilic addition reaction

The selective detection of sulfite and bisulfite ions with anthracene-based compounds (CN1 and CN2) as chemo-dosimeters is reported using fluorescence changes in DMSO:HEPES (70:30%), v/v buffer solution (pH 7.4). Upon treatment with sulfite and bisulfite ions, the fluorescence of the probes gets enhanced significantly at 424 nm. The detection of these ions occurs through the nucleophilic addition at the vinylic C-atom of the probes, which terminates the photo-induced electron transfer (PET) process and consequently enhances the fluorescence. This detection mechanism is well supported by 1H NMR titration, HR-MS and DFT/TD-DFT calculations. The pseudo-first-order rate constants for the addition sulfite (at pH 7.4) and bisulfite (at pH 5) to CN1 are determined to be 3.22×10−3 and 5.02×10−3 s−1, respectively. The limits of detection for sulfite and bisulfite are found to be 1.85×10−7 and 1.56×10−7 M, respectively. The probe CN1 was successfully applied to the detection of bisulfite ion in real samples.

An imidazo[1,5-α]pyridine-derivated fluorescence sensor for rapid and selective detection of sulfite

Sulfur-containing species are essential in the composition and the metabolism of the organisms, thus developing a full set of implements to cover all of them is still a favorable choice. Herein, we chose imidazo [1,5-α]pyridine moiety as the basic fluorophore for the detection of sulfite, and preliminarily completed the toolset since biothiols (GSH, Cys, Hcy), H2S, and PhSH could be detected by sensors based on the same backbone. The designed sensor, IPD-SFT, with structural novelty and large Stokes shift (130 nm), indicated the most attractive advantages of remarkably rapid response period (within 1 min) and high selectivity for sulfite from all the sulfur-containing species. Other practical properties included high sensitivity (LOD = 50 nM) and wide pH adaptability (5.0–11.0). Furthermore, IPD-SFT could monitor both exogenous and endogenous sulfite. It not only raised a potential tool for sulfite detection, but also preliminarily completed the toolset for all the sulfur-containing species. The development of such toolsets might reveal the sulfur-containing metabolism and corresponding physiology and pathological procedures.

Fabrication of oxidase-like polyaniline-MnO2 hybrid nanowires and their sensitive colorimetric detection of sulfite and ascorbic acid

Recently, nanomaterials-based oxidase-like artificial enzymes have attracted much attention due to their unique catalytic efficiency, high environmental stability and low-cost. In this study, we for the first time show the application of polyaniline (PANi)-MnO2 hybrid nanowires for oxidase mimicking. The PANi-MnO2 hybrid nanowires are prepared via a redox reaction between PANi nanowires and KMnO4. The as-prepared PANi-MnO2 hybrid nanowires exhibit an enhanced oxidase-like catalytic activity compared with individual PANi nanowires and MnO2 alone due to the synergistic catalytic effect between the two components. Based on the above findings, we construct PANi-MnO2 hybrid nanowires-based colorimetric assay for sensitive and selective detection of sulfite and ascorbic acid (AA). The detection limits of sulfite and AA are as low as 79 and 26 nM, respectively, which is much lower than many previous reported enzyme mimics-based colorimetric sensors. This work demonstrates a broad potential prospect of PANi-MnO2 hybrid nanowires in biotechnology, environmental science and food safety.

A rapid cell-permeating turn-on probe for sensitive and selective detection of sulfite in living cells.

A rapid cell-permeating probe NJUXJ-1 was introduced for sensitive and selective detection of sulfite in living cells. It generated a turn-on response to sulfite with high sensitivity (detection limit 13.0 nM) and selectivity (at a physiological level) and low toxicity. The fluorescence of the detecting system was steady for a wide pH range (5-8) and a long period of time (over 12 h). The most attractive point, its rapid cell-permeating ability, made it suitable for bioimaging with a 2 min incubation time and shortened the whole detecting period (cell-permeation and reaction), and thus could decrease background interference. It offered a convenient approach for determining exogenous or endogenous sulfite levels in living cells and further applications.

A highly sensitive and selective turn-on fluorescent probe for sulfite and its application in biological imaging

A new fluorescein-based probe (1) has been developed for the highly sensitive and selective detection of sulfite.

A new diketopyrrolopyrrole-based probe for sensitive and selective detection of sulfite in aqueous solution

A new probe was synthesized by incorporating an α,β -unsaturated ketone to a diketopyrrolopyrrole fluorophore. The probe had exhibited a selective and sensitive response to the sulfite against other thirteen anions and biothiols (Cys, Hcy and GSH), through the nucleophilic addition of sulfite to the alkene of probe with the detection limit of 0.1μM in HEPES (10mM, pH 7.4) THF/H2O (1:1, v/v). Meanwhile, it could be easily observed that the probe for sulfite changed from pink to colorless by the naked eye, and from pink to blue under UV lamp after the sulfite was added for 20min. The NMR and Mass spectral analysis demonstrated the expected addition of sulfite to the CC bonds.

Sulfite oxidase biosensors based on tetrathiafulvalene modified screen-printed carbon electrodes for sulfite determination in wine

Screen-printed carbon electrodes have been modified with tetrathiafulvalene and sulfite oxidase enzyme for the sensitive and selective detection of sulfite. Amperometric experimental conditions were optimized taking into account the importance of quantifying sulfite in wine samples and the inherent complexity of these samples, particularly red wine. The biosensor responds to sulfite giving a cathodic current (at +200mV vs screen-printed Ag/AgCl electrode and pH 6) in a wide concentration range, with a capability of detection of 6μM (α=β=0.05) at 60°C. The method has been applied to the determination of sulfite in white and red samples, with averages recoveries of 101.5% to 101.8%, respectively.

A new fluorescent turn-on probe for highly sensitive and selective detection of sulfite and bisulfite

Sulfur dioxide is a common air pollutant and extremely harmful to human health. After inhalation, SO2 is easily hydrated to two derivatives, sulfite and bisulfite. So it is valuable to develop an effective probe for these anions. In this work, a green-emissive fluorescent probe 1 is designed and synthesized, which employ 4-hydrazinyl-1, 8-naphthalimide as intramolecular charge transfer (ICT) fluorophore. Probe 1 is able to sense sulfite and bisulfite through fluorescence “turn-on” manner, and the detection limit for sufite is 0.56μM. The green emission induced by sulfite and bisulfate can be observed by naked eyes under UV irradiation. Compared with other anions used, probe 1 shows great selectivity toward sulfite or bisulfite. We illustrate the possible recognition mechanism of probe 1 and sulfite by NMR analysis and molecular modeling experiments. The real-time monitoring of SO2 release and cell imaging of sulfite is also investigated.