Fluorescent Probe For Hg2 Research Articles

A Fluorescent Probe for Hg2+ Specific Recognition Based on Xanthene and its Application in Food Detection and Cell Imaging.

The mercury-loving unit aminothiourea was introduced into the xanthene fluorophore to synthesized the probe molecule NXH. NXH has a specific response to Hg2+, and with the addition of (0 ~ 50 µM) Hg2+, the fluorescence intensity of the probe solution was quenched from 2352 a.u. to about 308 a.u. NXH exhibited excellent detection performance of high sensitivity (LOD = 96.3 nM), real-time response (105s), wide pH range (2.1 ~ 9.3), and strong anti-interference ability for Hg2+. At the same time, NXH has wide range of applications for Hg2+ detection, which can fluorescence imaging of Hg2+ in Hela cells and tea samples, and can also be made into Hg2+ detection test paper.

Synthesis of green fluorescent carbon dots and their application in mercury ion detection.

Green fluorescent carbon dots (GCDs) were synthesized using o-phenylenediamine and ethylenediamine through a one-step hydrothermal method, thereby eliminating the need for further processing. The GCDs exhibited strong green fluorescence that was effectively quenched by Hg2+ and Fe3+, with minimal interference from other metal ions, anions, and small biological molecules. By optimizing the buffer solution, interference from Fe3+ was mitigated, which enhanced the robustness of the GCDs as a fluorescence probe for Hg2+ detection. The detection range for Hg2+ was 0-100 μM, with a detection limit of 300 nM. The quenching mechanism was thoroughly investigated, and the GCDs were successfully applied to detect Hg2+ in real water samples, yielding satisfactory results. This work highlights the potential of GCDs for practical environmental monitoring and water quality analysis.

Tackling the kinetic dilemma of thioacetals in sensing of mercury through subtle structural changes of S to O

Novel fluorescent probes for Hg2+ are developing rapidly because Hg2+ has serious harm to the human health and natural environment. The deprotection reaction of thioacetal or thioketal based on sulfhydryl group is selective but slow. How to improve the reaction speed of deprotection methods on the premise of ensuring selectivity becomes a key problem. Herein, we designed and synthesized two coumarin ketal probes with similar structures: DTK and MTK. Both probes with highly similar structures could sense Hg2+, but sensing performance was special different. MTK replaced S with O in DTK, resulting in a sharp reduction in detection time (DTK took 18 min, while MTK achieved instantaneous detection of Hg2+), and has excellent sensitivity and selectivity. Moreover, a paper-based sensor was also designed as a convenient real-time device to detect Hg2+.

Multi-layered g-C3N4 as a Fluorescent Probe for Hg2+ Detection.

Hg2+ is one of the most toxic heavy metal ions that exist in the environment and it forms large numbers of toxic binary compounds. Accurate and rapid detection of the concentration of heavy metal ions is a prerequisite technology to achieve pollution control and prevention. Fluorescent probes have attracted extensive attention because of their high sensitivity, prominent precision, convenient and fast visualization of heavy metals. Herein, we report multi-layered graphitic carbon nitride via a simple thermopolymerization treatment as a very effectual fluorescent probe for sensitive and selective detection of Hg2+ with a limit of detection as low as 1.14nM.

A novel near-infrared fluorescence probe for detecting and imaging Hg2+ in living cells.

Fluorescence imaging, as one of the important means of biological lesion analysis, is widely used in medical analysis. To improve detection specificity, near-infrared emission fluorescent probes have been developed. Sensitive and selective near-infrared (NIR) fluorescent probes for Hg2+ , which is a heavy metal ion harmful to human health, are urgently needed to investigate the physiological toxicity of Hg2+ . The NIR fluorophore based on the traditional structure of rhodamine was prepared by introducing anthocyanin functional groups, and a rhodamine spiro ring structure was constructed to recognize Hg2+ (CCS-Hg). The probe CCS-Hg demonstrated good selectivity and high detection sensitivity for Hg2+ and the most likely mechanism was verified through theoretical calculations. We applied the probe CCS-Hg in the examination of Hg2+ distribution in living cells by NIR fluorescence imaging. This work provides a promising molecular tool for studying the toxicological effects of mercury ions in cell.

Recent advances on the preparation and application of graphene quantum dots for mercury detection: a systematic review

The mercury ion (Hg2+) is regarded as one of the toxic cations that is extremely harmful and dangerous to human health and the environment. With this growing awareness, it is imperative that facile and rapid sensing systems developed for the detection of Hg2+. Due to excellent sensitivity and selectivity, graphene quantum dots (GQDs), a zero-dimensional carbon nanomaterial, are attracting the attention of researchers as promising candidates as fluorescent probes for Hg2+ detection. This study aimed at conducting an in-depth review of recent advances into GQD-based materials as fluorescent probes in Hg2+ sensing. This systematic review was carried out by covering three main databases, namely, Scopus and Science Direct as the dominant databases, followed by Google Scholar as the supporting database. GQD-based materials encompassing bare GQDs, N-GQDs, B, N-GQDs, N, S-GQDs, N, K-GQDs, RhB-GQDs, Cys-GQDs, PEHA-GQD-DPA, Gly-GQDs, Mn(II)-N-GQDs, NH2–Ru@ SiO2-NGQDs and FA-GQDs were discussed thoroughly with regard to their synthesis strategies, along with their potential application in the detection of Hg2+. The doping of heteroatoms is envisaged to enhance the quantum yield and selectivity of bare GQDs. This review might unlock a wide range of opportunities for the application of various GQD-based materials as an adaptable, feasible and scalable approach to the detection of Hg2+.

An anthraquinone-based “turn-on” fluorescence probe for Hg2+ detection and its application in cell imaging

A new highly sensitive fluorescence “turn-on” probe (HgP1) based on anthraquinone derivatives for the detection of Hg2+ has been designed and developed. Based on desulfurization effect, probe HgP1 shows high selectivity towards Hg2+ in CH3OH/HEPES (10 mM, pH = 7.4, 1/1, v/v) solution over other analytes. The detection limit for Hg2+ is 8.2 nM. In addition, the probe shows good biocompatibility and has been successfully used in living cell imaging.

Sulfhydryl functionalized carbon quantum dots as a turn-off fluorescent probe for sensitive detection of Hg2.

Mercury ion (Hg2+) is one of the most toxic heavy metal ions and lowering the detection limit of Hg2+ is always a challenge in analytical chemistry and environmental analysis. In this work, sulfhydryl functionalized carbon quantum dots (HS-CQDs) were synthesized through a one-pot hydrothermal method. The obtained HS-CQDs were able to detect mercury ions Hg2+ rapidly and sensitively through fluorescence quenching, which may be ascribed to the formation of nonfluorescent ground-state complexes and electron transfer reaction between HS-CQDs and Hg2+. A modification of the HS-CQD surface by –SH was confirmed using Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The HS-CQDs sensing system obtained a good linear relationship over a Hg2+ concentration ranging from 0.45 μM to 2.1 μM with a detection limit of 12 nM. Delightfully, the sensor has been successfully used to detect Hg2+ in real samples with satisfactory results. This means that the sensor has the potential to be used for testing actual samples.

Reaction-based two novel fluorescent probes for Hg2+ detection using benzothiazole derivatives via ESIPT mechanism in aqueous solution and serum

Two novel Hg2+ fluorescent probes W-5 and W-6 have successfully been designed and synthesized based on benzothiazole derivatives as fluorophores and thiocarbonate moiety as recognition group. The structures of W-5 and W-6 were confirmed by NMR, HRMS and X-ray crystallography analysis. The probes W-5 and W-6 showed the ratio (F525/F405, large emission shift 120 nm) and “turn-on” fluorescence signals, respectively. Their advantages are excellent selectivity and anti-interference. Moreover, the probes W-5 and W-6 can provide excellent methods for the determination of Hg2+ in BSA and calf serums.

A new highly sensitive and selective fluorescent probe for Hg2+ and its application in living cells

A new coumarin-based probe (HgP) with two “S” groups was designed and synthesized The probe HgP exhibited a fast response time (<2 min) and high selectivity (DL, 2.2 × 10−7 mol/L). Furthermore, its capability of biological application was stu died, and the results showed that it could be applied to recognize Hg2+ in living cells (HK2 cells).

A coumarin-based fluorescent probe for Hg2+ and its application in living cells and zebrafish.

Mercury (Hg) is a heavy metal with high toxicity and easy migration; it can be enriched through the food chain, and cause serious threats to the natural environment and human health. So, the development of a method that can be used to detect mercury ions (Hg2+ ) in the environment, in cells, and in organisms is very important. Here, a new 7-hydroxycoumarin-derived carbonothioate-based probe (CC-Hg) was designed and synthesized for detection of Hg2+ . After addition of Hg2+ , a large fluorescence enhancement was observed due to the formation of 7-hydroxyl, which reinforced the intramolecular charge transfer process. The CC-Hg probe had good water solubility and selectivity. Moreover, the probe was able to detect Hg2+ quantitatively over the concentration range 0-2 μM and with a detection limit of 7.9 nM. Importantly, we successfully applied the probe to detect Hg2+ in water samples, in living cells, and in zebrafish. The experimental results demonstrated its potential value in practical applications.

Silver ion-doped CdTe quantum dots as fluorescent probe for Hg2+ detection.

Mercury(ii), which is a well-known toxic species, exists in the industrial waste water in many cases. In the present work, CdTe quantum dots (QDs) are studied as a fluorescence probe for Hg2+ detection. Ag ions are induced to QDs to enlarge their detection concentration range. l-cysteine is employed in the QD-based fluorescence probe to connect QDs with Hg2+. X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy results indicate the formation of zinc blende CdTe QDs with sizes of ∼5 nm and the existence of Ag+ in crystalline CdTe. Photoluminescence (PL) spectra and PL decay spectra were acquired to investigate the emission mechanism of Ag-doped CdTe QDs, revealing multi-emission in QD samples with higher concentrations of Ag+ doping. The highest PL quantum yield of the QD samples was 59.4%. Furthermore, the relationship between the fluorescence intensity and the concentration of Hg2+ has been established. Two linear relationships were obtained for the plot of F/F0 against Hg2+ concentration, enlarging the detection concentration range of Hg2+.

A New Dual-response Behavior Chemosensor Based on 2-(1H-dithienobenzoimidazole)-pyridine Unit for Hg2+ Detection

A novel chemosensor has been synthesized by using 2- (1H-dithienobenzoimidazole)pyridine (DBP) as a receptor unit. The compound was highly selective towards Hg2+ with significant absorption change, which could be easily seen by ‘naked-eye’. Moreover, it showed highly sensitive towards Hg2+ with obvious fluorescence change from bright blue to dark in methanol. The limit of detection for Hg2+ detection is determined to be 3.17 × 10–8 mol L–1 according to fluorescence titration, and the stoichiometry between DBP and Hg2+ is calculated to be 1:1. Therefore, the DBP could be used as a potential candidate ‘naked-eye’ colorimetric sensor or a “turn off” fluorescence probe for Hg2+ detection.

A novel turn-on fluorescent probe for Hg2+ detection based on rhodamine B spirolactam derivative

ABSTRACTIn this work, a new turn-on fluorescent probe 1 for Hg2+ ions detection based on rhodamine B spirolactam was reported. Among tested metal ions, probe 1 shows high selectivity towards Hg2+ in the the mixture solution of methanol and 0.02 M HEPES buffer (V/V = 9:1, pH = 7.2). No absorption and emission band of probe 1 was observed in the range from 450 to 700 nm. While only addition of Hg2+ to probe 1 could lead to appearance of a new absorption band centered at 553 nm and a fluorescence emission band around 577 nm upon excitation at 520 nm. Moreover, it exhibits excellent linear relationship (R2 = 0.9993) between fluorescence intensity at 577 nm and the concentration of Hg2+ from 1.6 to 32 μM. The sensing mechanism was proven to be spirolactam ring open induced by Hg2+ through 1H NMR, MS, absorption and fluorescence spectra. In addition, probe 1 could detect Hg2+ in real water samples and on filter paper, which demonstrates its application in environment science.

A novel quick and highly selective “turn-on” fluorescent probe for Hg2+ and its application

In the present work, we reported the simple synthetic strategy of fluorescent probe BAA. In order to increase the binding ability and selectivity of the probe for Hg2+, an alkynyl group was introduced on the adjacent position of the azo group of the probe. The molecular structure of BAA was characterized by 1H NMR, 13C NMR, IR, and MALDI-TOF. Spectrum analysis indicated that BAA exhibited high selective turn-on fluorescence signal and rapid response (about 10 s) to Hg2+. The selectivity can also be visualized under UV light, the BAA shows green fluorescence emission only in the presence of Hg2+. The stoichiometric ratio (1:1) between the probe and Hg2+ could be obtained by the Job-plot and ESI-MS analysis, and was confirmed by quantum chemical calculations. The detection limit of Hg2+ was 1.30 × 10−7 M in aqueous media. We have demonstrated the suggested probe can detect Hg2+ in lake water samples with satisfying results. Moreover, it exhibits excellent membrane permeability and has been successfully used for detection of Hg2+ in MCF-7 living cells by confocal fluorescence imaging. The explored facile “turn-on” Hg2+ fluorescent probe here may have the further potential applications in environmental testing, biomedicine and food analysis.

A Quninolylthiazole Derivatives as an ICT-Based Fluorescent Probe of Hg(II) and its Application in Ratiometric Imaging in Live HeLa Cells.

As a structural analogue of pyridylthiazole, 2-(2-benzothiazoyl)-phenylethynylquinoline (QBT) was designed as a fluorescent probe for Hg(II) based on an intramolecular charge transfer (ICT) mechanism. The compound was synthesized in three steps starting from 6-bromo-2-methylquinoline, with moderate yield. Corresponding studies on the optical properties of QBT indicate that changes in the fluorescence ratio of QBT in response to Hg(II) could be quantified based on dual-emission changes. More specifically, the emission spectrum of QBT before and after interactions with Hg(II) exhibited a remarkable red shift of about 120nm, which is rarely reported in ICT-based fluorescent sensors. Finally, QBT was applied in the two-channel imaging of Hg(II) in live HeLa cells.

Synthesis of multi-functional green fluorescence carbon dots and their applications as a fluorescent probe for Hg2+ detection and zebrafish imaging

Green fluorescence carbon dots for mercury detection and zebrafish imaging.

A novel fluorescent probe for Hg2+ detection in a wide pH range and its application in living cell imaging

A novel fluorescent probe (XL-1) exhibited over 50-fold enhanced fluorescence in the presence of Hg2+ and no interference could be produced by other metal ions, anions and amino acids.

A portable RGB sensing gadget for sensitive detection of Hg2+ using cysteamine-capped QDs as fluorescence probe

A facile one-pot method was proposed to synthesis cysteamine capped CdTe QDs with a high quantum yield 30%. In the synthesis process, nitrogen protection, ultrasonic treatment, and light irradiation were unnecessary. Additionally, potassium tellurite was used instead of Te powder as Te source, avoiding of the time-consuming Te powder dissolution process. The prepared QDs were found to be Hg2+ sensitive. The detection linear range for Hg2+ was from 5 to 300nM, and the detection limit was calculated to be 1nM. The detection mechanism was mainly ascribed to the electron transfer from cysteamine capped QDs to Hg2+, resulting in a fluorescence quenching phenomenon. In addition, we developed a portable RGB sensing gadget with the QDs as fluorescence probe for Hg2+ detection, and the linear range was from 5 to 200nM. Furthermore, the gadget was applied for Hg2+ detection in tap water sample. The results showed that the average recoveries in real tap water sample were in the range from 97.2% to 115.3%, which indicated that accuracy and precision were satisfactory for practical application requirements.

Carbamodithioate-based fluorescent chemosensor for Hg(II): a staged response approach and investigation into the sensing mechanism.

Carbamodithioate-based compound C1 was designed and synthesized as a new fluorescent probe for Hg2+ ions. Upon the addition of Hg2+ ions, it displayed a rare staged response: the emission spectra of C1 first showed an apparent red-shift, followed by a dramatic decrease. To investigate the sensing mechanism, control compounds C2 with the same phenanthroimidazole unit and C3 with the same carbamodithioate functionality were synthesized. On comparison, the first step sensing process was ascribed to decreasing photoinduced electron transfer on the coordination of Hg2+ with the lone pair electrons of the nitrogen atom on the phenanthroimidazole ring. The affinity of Hg2+ and the carbamodithioate unit with four sulfur atoms then induced changes in intramolecular charge transfer efficiency and the second step fluorescent response.