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(A) The plot of the fluorescence intensity versus the concentration of Hg 2+ spiked in different matrices of tap water (A-1), Yellow river water (A-2), and deionized water (A-3). (B) The colorimetric fluorescence images of RhB on filter paper after the addition of different concentrations of Hg 2+ (from left to right, 0, 0.1, 0.3, 0.5, 0.7, 0.9, 1.1 ?M). (B-1 and 2) The colorimetric images set of the RhB spot in the absence or presence of different concentrations of Hg 2+ respectively. (B-3 and 4) The fluorescence images set of the RhB spot in the absence or presence of different concentrations of Hg 2+ , respectively. B-3 and B-4 images were taken under the illumination of a 365 nm UV lamp.
Source publication
Nowadays, the development of a multifunction system for the simultaneous multiple signal amplification detection and fast removal of Hg(2+) remains a major challenge. Herein, we for the first time used gold nanoparticles (Au NPs) and the corresponding filter membrane as chemosensors and adsorbents for dual signal amplification detection and fast re...
Contexts in source publication
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... size and morphology of the Au NPs were characterized using transmission electron microscopy (TEM) and UV-vis spectroscopy. As shown in Fig. 1C, the Au NPs were largely monodispersed and roughly spherical. The average particle diameter is found to be approximately 13 nm (Fig. S4 ?). When Hg 2+ and/or NaBH 4 were added to the dispersion of Au NPs, there was no aggregation of Au NPs induced by Hg 2+ with low concentrations (0-100 nM) due to the formation of gold amal- gamation. The as-prepared citrate-capped Au NPs exhibited typical absorption spectra for such particles with a maximum centered at 525 nm (Fig. 1F). After adding Hg 2+ , the absorption band slightly blue-shifted to around 522 nm, indicating that the Hg 2+ layer was formed on the surface of Au NPs. 49 Also the color of Au NP solution remained the same after the formation of gold amalgam (Fig. 1G). X-ray photoelectron spectroscopy (XPS) measurements were performed for the surface elemental analysis. As shown in Fig. S5, ? the whole spectrum of mercury- treated Au NPs clearly revealed that carbon, oxygen, sodium, gold, and mercury were present on the surface of Au NPs, indi- cating that the Au NPs were capped by citrate and mercury. In addition, the Hg 4f electron spectrum could be well-resolved with doublets with Hg 4f 7/2 and Hg 4f 5/2 binding energies of 99.79 and 103.89 eV (Fig. 1H), which indicate that Hg 0 existed on the surface of Au NPs. 27 ...
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... evaluate the applicability of the gold amalgam catalyzing the reduction of RhB to real samples, tap water (sampled from our lab) and Yellow river water (coliform group exceeded 50%, other indicators were normal, sampled from Lan Zhou city, Gansu province) samples spiked with various concentrations of Hg 2+ were tested. Fig. 4A shows the response of the fluorescence and colorimetric assay to Yellow river water, tap water, and de- ionized water samples with various concentrations of Hg 2+ . The sensor response linearly decreased with increasing Hg 2+ concen- tration. As can be seen in Fig. 4A, there was no apparent differ- ence in the fluorescence quenching efficiency of RhB by Hg 2+ in the three matrices (Yellow river water, tap water, deionized water) at different concentrations, indicating that the fluo- rescence and colorimetric assay can detect Hg 2+ without being affected by the interfering Yellow river water and tap water environment (other metal ions and other organic contami- nants). To further demonstrate the applicability of our assay in practical applications, we performed recovery experiments using spiked deionized water, tap water and Yellow river water samples. As can be seen in Table 1, the recovery of Hg 2+ solu- tion with various concentrations for the three samples was stat- istically close to 100% (range from 96.3% to 102%), showing the accurate detection of Hg 2+ in real ...
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... evaluate the applicability of the gold amalgam catalyzing the reduction of RhB to real samples, tap water (sampled from our lab) and Yellow river water (coliform group exceeded 50%, other indicators were normal, sampled from Lan Zhou city, Gansu province) samples spiked with various concentrations of Hg 2+ were tested. Fig. 4A shows the response of the fluorescence and colorimetric assay to Yellow river water, tap water, and de- ionized water samples with various concentrations of Hg 2+ . The sensor response linearly decreased with increasing Hg 2+ concen- tration. As can be seen in Fig. 4A, there was no apparent differ- ence in the fluorescence quenching efficiency of RhB by Hg 2+ in the three matrices (Yellow river water, tap water, deionized water) at different concentrations, indicating that the fluo- rescence and colorimetric assay can detect Hg 2+ without being affected by the interfering Yellow river water and tap water environment (other metal ions and other organic contami- nants). To further demonstrate the applicability of our assay in practical applications, we performed recovery experiments using spiked deionized water, tap water and Yellow river water samples. As can be seen in Table 1, the recovery of Hg 2+ solu- tion with various concentrations for the three samples was stat- istically close to 100% (range from 96.3% to 102%), showing the accurate detection of Hg 2+ in real ...
Citations
... Finally, the kinetics of interaction and the adsorption capacity at different temperatures were studied. The system, consisting of silver nanoparticles and a photopolymerizable monomer (PEGDA), represents one of the few systems that involve the use of noble metal nanostructures for the removal of heavy metals from water [66][67][68][69][70] and, in addition, the only one that involves a three-dimensional structuring of the filter. ...
... This result indicates that the enhancement of the provided energy encourages the adsorption of Hg(II) into the metal core of AgNPs, forming the amalgam Hg/Ag, as reported in the XPS study and our previous research [68,83]. A comparison with the literature [66][67][68][69][70] about the performance of filtration toward heavy metal ions is reported in Table S2 of the Supporting Information. ...
Nowadays, due to water pollution, more and more living beings are exposed to dangerous compounds, which can lead to them contracting diseases. The removal of contaminants (including heavy metals) from water is, therefore, a necessary aspect to guarantee the well-being of living beings. Among the most used techniques, the employment of adsorbent materials is certainly advantageous, as they are easy to synthesize and are cheap. In this work, poly(ethylene glycol) diacrylate (PEGDA) hydrogels doped with silver nanoparticles (AgNPs) for removing Hg(II) ions from water are presented. AgNPs were embedded in PEGDA-based matrices by using a photo-polymerizable solution. By exploiting a custom-made 3D printer, the filters were synthesized. The kinetics of interaction was studied, revealing that the adsorption equilibrium is achieved in 8 h. Subsequently, the adsorption isotherms of PEGDA doped with AgNPs towards Hg(II) ions were studied at different temperatures (4 °C, 25 °C, and 50 °C). In all cases, the best isotherm model was the Langmuir one (revealing that the chemisorption is the driving process and the most favorable one), with maximum adsorption capacities equal to 0.55, 0.57, and 0.61 mg/g, respectively. Finally, the removal efficiency was evaluated for the three temperatures, obtaining for 4 °C, 25 °C, and 50 °C the values 94%, 94%, and 86%, respectively.
... . Hg 2+ removal has been attempted using remediation techniques like precipitation, ion-exchange, nanofiltration, and adsorption, as a parallel branch [12,13]. Fluorescence sensing and adsorption have gained widespread attention for monitoring and segregating pollutants due to their eco-friendliness, cost-effectiveness, and simple operation [14,15]. ...
... Wang and co-workers used AuNPs as chemosensors for the dual signal amplification detection of Hg 2+ (Fig. 6e). 68 This simple method presents some notable advantages, including simple synthesis, rapid response, exceptional selectivity, and high sensitivity. The proposed system relies on the formation of gold amalgam and a gold amalgam-based reaction involving rhodamine B (RhB) and NaBH 4 , which exhibits fluorescence and colorimetric sensing functionalities. ...
The shortage of freshwater resources caused by heavy metal pollution is an acute global issue, which has a great impact on environmental protection and human health. Therefore, the exploitation of new strategies for designing and synthesizing green, efficient, and economical materials for the detection and removal of heavy metal ions is crucial. Among the various methods for the detection and removal of heavy ions, advanced functional systems including nanomaterials, polymers, porous materials, and biomaterials have attracted considerable attention over the past several years due to their capabilities of real-time detection, excellent removal efficiency, anti-interference, quick response, high selectivity, and low limit of detection. In this tutorial review, we review the general design principles underlying the aforementioned functional materials, and in particular highlight the fundamental mechanisms and specific examples of detecting and removing heavy metal ions. Additionally, the methods which enhance water purification quality using these functional materials have been reviewed, also current challenges and opportunities in this exciting field have been highlighted, including the fabrication, subsequent treatment, and potential future applications of such functional materials. We envision that this tutorial review will provide invaluable guidance for the design of functional materials tailored towards the detection and removal of heavy metals, thereby expediting the development of high-performance materials and fostering the development of more efficient approaches to water pollution remediation.
... For the past few decades, luminol has been used for the generation of chemiluminescent signals, but in natural media, luminol obtains a very weak signal. To enhance the chemiluminescent signal (CL signal), enzymes have been used for a long time (Chen et al., 2017a(Chen et al., , 2017b. Some enzyme catalytic activity can be inhibited by the attachment of metal ions to the binding site of the enzyme. ...
... AuNPs have high electrical conductivity and a high affinity for metals such as Hg, As and Pb . A lot of researchers have published on Hg 21 removal with AuNPs (Chen et al., 2017a(Chen et al., , 2017bHu et al., 2019;Hua et al., 2020). AuNPs work as electrodes with proteins, amino acids, DNA or some other materials (Herrero et al., 2001;Karimi-Maleh et al., 2019). ...
... Advanced techniques and materials, such as aptamer-based amperometric and chemiluminescent detection and biosorption, have been widely applied in Hg 21 removal processes. They have many advantages but also some limitations such as experimental condition and handling, complex instruments and background interference (Chen et al., 2017a(Chen et al., , 2017b. Metal NPs are very efficient in Hg 21 detection, but even they can cause toxicity (Hondroulis et al., 2010).The toxicity of metal NPs is the big issue and future challenge for researchers. ...
Purpose-This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. Design/methodology/approach-Different nano-and bio-materials allowed for the development of a variety of biosensors-colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors-are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples. Findings-This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples. Originality/value-This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel Mercury ions detection sensors and encourage them for further research/development.
... It is believed that SCN is the best candidate for the sorption of Hg(II) from the polluted water because it contains chemically hard N atom and soft S atom, in which hard metal ion can coordinate with N atom while metal ions with S atom. Chen et al. (2017) synthesized an innovative MOF, FJI-H12, formed in the presence of Co 2+ , SCN and 2,4,6-tri(1imidazolyl)-1,3,5-trizaine. FJI-H12 can be removed completely and selectively from water or wastewater. ...
Effective and substantial remediation of contaminants especially heavy metals from water is still a big challenge in terms of both environmental and biological perspectives because of their adverse effects on the human health. Many techniques including adsorption, ion exchange, co-precipitation, chemical reduction, ultrafiltration, etc. are reported for eliminating heavy metal ions from the water. However, adsorption has preferred because of its simple and easy handlings. Several types of adsorbents are observed and documented well for the purpose. Recently, highly porous metal-organic frameworks (MOFs) were developed by incorporating metals and organic ligands together and claimed as potent adsorbents for the remediation of highly toxic heavy metals from the aqueous solutions due to their unique features like greater surface area, high chemical stability, green and reuse material, etc. In this review, the authors discussed systematically some recent developments about secure MOFs to eliminate the toxic metals such as arsenic (both arsenite and arsenate), chromium(VI), cadmium (Cd), mercury (Hg) and lead (Pb). MOFs are observed as the most efficient adsorbents with greater selectivity as well as high adsorption capacity for metallic contamination.
Graphical abstract
... Accordingly, the Ag NP-LNP suspension can be applied as a colorimetric sensor for the visually detection of Hg 2+ on site via monitoring the color change. The sensitivity of the Ag NP-LNP suspension detecting Hg 2+ is higher as compared with the reported materials [32][33][34]. The negative charge of LNPs and lignin accounts for the ultra-sensitivity of the Ag NP-LNP suspension. ...
Lignin nanoparticles (LNPs) were employed as the reducing and stabilizing agent in the preparation of silver nanoparticles (Ag NPs) from silver nitrate under solar light. The Ag NPs were characterized by spectrophotometry, TEM, HRTEM, element mapping, XRD and XPS. The formation of Ag NPs and the structural changes of lignin during the reaction was monitored by analysis via ³¹P NMR, ¹H NMR and ¹³C NMR. The Ag NPs have uniform shape and an average size of ~14 nm. They were loaded onto the surface of LNPs and entangled in lignin. The resulting Ag NP-LNP suspension displays an ultrasensitive and selective optical response to Hg (II) in giving a color change from yellow to colorless. The assay was performed by spectrophotometry at 450 nm. The analytically useful range extends from 5 nM to 100 nM of Hg (II), and the limit of detection is 1.4 nM in deionized water and 1.8 nM in spiked tap water. This is lower than the threshold level (10 nM) in drinking water specified by the US Environmental Protection Agency.
Graphical abstractSchematic representation of the solar light induced synthesis of sliver nanoparticles (Ag NPs) by lignin nanoparticles (LNPs) and their application to colorimetric determination of Hg²⁺.
... 52 Meanwhile, the peak for the group of Au−N is located at 414 nm. 53 Furthermore, to explore the growth mechanism of CuFeSe 2 / Au nanospheres, a time-dependent growth process was monitored by SEM ( Figure S13), and the experimental results and related discussion are given in the Supporting Information. We also found that the amount of HAuCl 4 ·4H 2 O plays an important role in the growth of CuFeSe 2 /Au nanospheres ( Figure S14). ...
Rapid and sensitive identification of tumor biomarker or cancer cells in their nascent stage based on surface enhanced Raman scattering (SERS) are still an attractive challenge due to low molecular affinity for metal surface, the complexity of the sample, and low efficiency use of hotspots in one- or two-dimensional geometries. Here, we demonstrated a novel kind of renewable CuFeSe2/Au heterostructured nanospheres with hierarchical porous for specific and sensitive detection of lung cancer biomarkers of aldehydes and lung cancer cells. The heterostructured nanospheres were constructed by loading an Au shell formed by photoreduction on the CuFeSe2 frameworks. P-aminothiophenol (4-ATP) as Raman-active probe molecule was first grafted on CuFeSe2/Au nanospheres, and then the gaseous aldehyde molecules were sensitively bonded onto the nanospheres by the formation C=N bond, with the detection limits of the 1.0 ppb. Moreover, the resulting folic acid (FA)-conjugated nanospheres present a high SERS activity to Rhodamine B isothiocyanate (RBITC), which can be used to specifically recognize and sensitively detect the A549 cells. Our study suggested that the synthesized renewable CuFeSe2/Au heterostructured nanospheres as a multimodal platform could find a wide range of application in the field of medicine, biotechnology and environmental sciences.
... Gold nanoparticles and corresponding filter membrane are prepared by Wang et al. for fast removal of Hg 2+ . 99% Hg 2+ in the Yellow River water and tap water can be quickly removed in a short time by the membrane-fixed Au NPs [117]. ...
Background
Due to its high toxicity and bioaccumulation, the existence of mercury in the environment is always a big threat to human beings. In order to control mercury pollution, scientists have put great efforts in the past decades.
Methods
Precipitation, adsorption, membrane separation, biological treatment and ion exchange are reviewed as a remover for mercury removal. For each material type, we not only reported on the removal mechanism, but also discussed the best areas for it. The correlation method and step-to-step focusing method have been used for references.
Conclusion
With the exploration and application of research, people have mastered a variety of mature technologies for the treatment of mercury-containing wastewater. Using inexpensive adsorbents is a cost-effective method for treating low concentrations of heavy metal wastewater. Ion exchange with a fast removal rate has been widely used in the field of heavy metal removal from wastewater. The biological treatment method can effectively treat low-concentration mercurycontaining wastewater. However, there is still a need to develop novel mercury removers with high capacity, fast removal rate, and low removal limit. Nanomaterials with a high specific surface area on substrate with synergistic effects, such as high adsorption and ion exchange, are the future research points.
... For this, soluble mercury ions (Hg 2+ , Hg 2 2+ , CH 3 Hg + ) are reduced to elemental mercury (Hg 0 ), followed by subsequent amalgamation with a metal. Several such systems have been described [19][20][21][22][23][24] . One example is the use of gold nanoparticles coated with sodium citrate, where the latter acts as electron donor to facilitate reduction of mercury and formation of Au 3 Hg 22 . ...
Retrieval of mercury from aqueous streams has significant environmental and societal importance due to its very high toxicity and mobility. We present here a method to retrieve mercury from aqueous feeds via electrochemical alloy formation on thin platinum films. This application is a green and effective alternative to traditional chemical decontamination techniques. Under applied potential, mercury ions in solution form a stable PtHg4 alloy with platinum on the cathode. A 100 nanometres platinum film was fully converted to a 750 nanometres thick layer of PtHg4. The overall removal capacity is very high, > 88 g mercury per cm³. The electrodes can easily be regenerated after use. Efficient and selective decontamination is possible in a wide pH range, allowing processing of industrial, municipal, and natural waters. The method is suited for both high and low concentrations of mercury and can reduce mercury levels far below the limits allowed in drinking water.
... [25][26][27][28][29][30][31] With nanomaterials, signal amplification can be easily accomplished and owing to this the field of biochemical sensing using nanomaterials has witnessed a rapid development in the past 20 years. [32][33][34][35][36][37][38][39] Very recently, a method based on modified gold nanoparticles (Au NPs) has been reported for arsenic detection down to 100 ppt, which is two orders of magnitude lower than the WHO guideline. 40 They modified Au NPs using glutathione (GSH), dithiothreitol (DTT) and cysteine (Cys) based on Au-S bonds. ...
Nowadays, there is an urgent demand to develop methods for rapid and onsite determination of toxic arsenic in environmental samples. Herein, we propose a colorimetric method for ultrasensitive point-of-care testing of arsenic using unmodified gold nanoparticles (Au NPs). This system is based on the Au NPs catalyzed redox reaction between Rhodamine B (RhB) and sodium borohydride (NaBH4) which leads to color change of the reaction solution. AsO2⁻ significantly inhibits the catalytic activity of Au NPs so that it can be quantified by the colorimetric measurement. The method shows high sensitivity with a detection limit of 0.64 ppb, which is below the threshold of arsenic in drinking water recommended by WHO. It also demonstrates high selectivity among other interfering ions. Samples of daily life are analyzed using this method, and the results agree with those obtained from standard inductively coupled plasma mass spectrometry.
