查找使用阿拉丁产品的科研文献

Vertically-Ordered Mesoporous Silica Films for Electrochemical Detection of Hg(II) Ion in Pharmaceuticals and Soil Samples

Zhang Mengqi,Zou Yanqi,Zhou Xiaoyu,Yan Fei,Ding Zhanling

Rapid and simple determination of mercury ion (Hg2+) in pharmaceuticals and soil samples is vital for human health and the environmental monitoring. Vertically-ordered mesoporous silica films (VMSF) supported by the indium tin oxide (ITO) electrode surface were prepared by electrochemically assisted self-assembly method and utilized for electrochemical detection of Hg2+. Owing to the negatively charged channel walls and ultrasmall pore diameter, VMSF displays obvious cationic selectivity and has highly electrostatic interaction for Hg2+, giving rise to the strong electrochemical signals. By recording the anodic stripping signals of adsorbed Hg2+ using differential pulse voltammetry, quantitative detection of Hg2+ was achieved with a wide linear range (0.2 μM–20 μM) and a low limit of detection (3 nM). Furthermore, considering the anti-fouling and anti-interference capacity of VMSF, the proposed VMSF/ITO sensor has been successfully applied to detect Hg2+ in pharmaceuticals and soil samples without tedious pretreatment processes of samples.

Colorimetric determination of Hg(II) ions based on core/shell Au@MnO2 nanoparticles with oxidase-like activity

Xianqiang Song,Xin Chen,Zhaoxiong Liang,Dan Xu,Yong Liang

In this work, we present core/shell Au@MnO 2 nanoparticles-based visual sensing strategy for mercury ion (Hg 2+ ) detection. The MnO 2 shell of Au@MnO 2 nanoparticles catalyzes the oxidation reaction between tetramethylbenzidine (TMB) and oxygen in the air, generating blue derivative (oxTMB) with an absorption peak at 650 nm. Glutathione (GSH) inhibits the formation of oxTMB, reversing the reaction and turning it back into colorless TMB molecules. While in the existence of Hg 2+ , GSH binds to Hg 2+ due to the strong affinity between the Hg 2+ and the -SH, and in this situation, Au@MnO 2 catalyzes the oxidation of TMB to make the solution become blue. Using the colorimetric sensor, the detection limit of Hg 2+ reached as low as 0.473 nM by UV–vis spectroscopy and 1 nM under the naked eye observation, which is lower than toxicity level of Hg 2+ (10 nM) formulated by the U.S. Environmental Protection Agency.

Synthesis of novel thiol-modified lysozyme coated magnetic nanoparticles for the high selective adsorption of Hg(II)

Yue Sun,Yingpeng Gu,Xiao Li,Rajendra Prasad Singh

As a common heavy metal ion in wastewater, Hg(II) has high toxicity even at low concentration. In this study, a novel magnetic nano-adsorbent (FS@PTL-SH) was synthesized by modifying thiol groups on phase-transited lysozyme (PTL) coated magnetic nanoparticles . FS@PTL-SH exhibited superior adsorption performance for Hg(II) in a wide pH range. The maximum adsorption capacity of FS@PTL-SH fitted by Langmuir model could reach 1001.21 mg/g at 298 K, and 90% of the equilibrium uptake could be achieved within 5 min. The interference of inorganic ions and organic complexing agents was limited even at high concentrations. High adsorption selectivity of Hg(II) was observed in the mixed solution containing various heavy metal ions. Moreover, FS@PTL-SH could still maintain above 90% of the adsorption capacity after five adsorption–desorption cycles. For the mechanisms, the adsorption of FS@PTL-SH for Hg(II) was mainly relied on the strong complexation of the surface functional groups, especially thiol groups.

Mechanochemical synthesis of oxygenated alkynyl carbon materials with excellent Hg(II) adsorption performance from CaC2 and carbonates

Yingjie Li,Songping Li,Xinyi Xu,Hong Meng,Yingzhou Lu,Chunxi Li

Adsorptive removal of heavy metal ions from wastewater is very important, and the key is the development of efficient sorbents. In this work, oxygenated alkynyl carbon materials (OACMs) were synthesized via mechanochemical reaction of CaC 2 and a carbonate (CaCO 3 , Na 2 CO 3 , or NaHCO 3 ) at ambient temperature. The resultant OACMs are micro mesoporous carbon nanomaterials with high specific area (>648 m 2  g −1 ), highly crosslinked texture, and rich alkynyl and oxygenated groups. The OACMs exhibit excellent Hg(II) adsorption due to the soft acid-soft base interaction between alkynyl and Hg(II), and OACM-3 derived from CaC 2 and NaHCO 3 has the saturated Hg(II) adsorbance of 483.9 mg g −1 along with good selectivity and recyclability. The adsorption is mainly chemisorption following the Langmuir mode. OACM-3 also shows high adsorbance for other heavy metal ions, e.g. 256.6 mg g −1 for Pb(II), 232.4 mg g −1 for Zn(II), and 198.7 mg g −1 for Cu(II). This work expands the mechnochemical reaction of CaC 2 with carbonates and possibly other oxyanionic salts, provides a new synthesis approach for functional alkynyl carbon materials with excellent adsorption performance for heavy metal ions, as well as a feasible approach for CO 2 resource utilization.

Thiol/methylthio-functionalized porous aromatic frameworks for simultaneous capture of aromatic pollutants and Hg(II) from water

Xinrong Liao,Guoqiang Yu,Ruiqing Luo,Qiang Wang,Chiyang He,Shaorong Liu

Simultaneously capturing organic pollutants and heavy metal can greatly reduce the water remediation time and cost, however it is still a great challenge presently. Herein, two novel thiol/methylthio–functionalized porous aromatic frameworks were synthesized as sorbents via the Sonogashira–Hagihara reaction of 1,3,5–triethynylbenzene and 1,3,5–tris(4–bromophenyl) benzene, the subsequent chloromethylation of the phenyl rings, and the final nucleophile substitution of –Cl groups by NaSH/NaSMe. These two sorbents were characterized by FT–IR spectra, energy dispersive X-ray spectra, scanning electron microscope , nitrogen adsorption analysis, thermo–gravimetric analysis, and elemental analyses. Adsorption experiments displayed that new sorbents had high uptake abilities and fast adsorption kinetics for aromatic pollutants and mercury (II) (Hg(II)). The maximum adsorption capacity ( Q max ) of toluene and m –xylene on both new sorbents were 531.9–571.4 mg/g with the kinetic binding rate constants ( k obs ) of 0.00276–0.02422 g/mg/min, and the Q max values of Hg(II) were 148.1–180.3 mg/g with k obs of 0.00592–0.01573 g/mg/min. Moreover, new sorbents indicated high simultaneous uptake abilities for these pollutants with good reusability, and finally they were successfully applied to the simultaneous remediation of these pollutants in two simulated sewages with high and low concentration, indicating their great practical application potential in wastewater remediation.

Biomimetic nanopore for sensitive and selective detection of Hg(II) in conjunction with single-walled carbon nanotubes

Qingfeng Zhai,Siqi Zhang,Hong Jiang,Qin Wei,Erkang Wang,Jiahai Wang

In this article, we propose a new method for selective detection of Hg2+ based on a biomimetic nanopore sensing platform in combination with single-walled carbon nanotubes (SWNTs). As is well known, folded DNA in the presence of Hg2+ can be separated from single-stranded DNA through SWNTs, and the folded DNA can be quantitated with cone-shaped nanopore whose surface was coated by polyethyleneimine (PEI)/Zr4+. Both sensitivity and selectivity based on this paradigm can be guaranteed without immobilization of probes on the nanopore surface. This approach can warrant the detection limit for Hg2+ down to 8.3 nM (S/N = 3) with high selectivity against other metal ions. Moreover, the application of the sensor for lake water shows that the proposed method works well for real samples. This research demonstrates an alternative approach to detect targets of interest that holds high prospects for detecting other biomolecules or metal ions in the near future.

Multifunctional antibacterial enhanced amoxicillin carbon nanodots for the detection of Hg (II) and methanol in edible alcohol

Hongbo Wang,Xinyu Zhao,Xuechun Zhou,Xiaoyu He,Lizhi Xiao,Xun Zhang,Ying Zhang,Shu Nie,Yingnan Jiang

Amoxicillin was used as the sole precursor to rapidly synthesize amoxicillin carbon nanodots via a one-step microwave method. The diameter of the amoxicillin carbon nanodots was concentrated at 1.8 ± 0.6 nm, with fluorescence excitation-dependent characteristics. After characterization, the carbon nanodots retained some of the amoxicillin structure, exhibiting low biological toxicity and good antibacterial activity. Due to the formation of the carbon dots structure, the hydrophilicity and water solubility of the amoxicillin carbon nanodots improved. An antibacterial plate experiment further showed that the antibacterial performance of the amoxicillin carbon nanodots was higher than that of the original amoxicillin. The amoxicillin carbon nanodots could quickly and conveniently detect Hg 2+ via changes in their fluorescence intensity. Moreover, several aliphatic alcohols could be distinguished and quantified based on the fluorescence intensity increase of the amoxicillin carbon nanodots. Most importantly, the amoxicillin carbon nanodots quickly identified and quantified methanol mixed in edible alcohol. These multifunctional amoxicillin carbon nanodots have broad application prospects in antibiosis, toxic Hg 2+ detection, and identification and detection of several aliphatic alcohols, especially the microfluorometric determination of methanol in edible alcoholic beverages.

Recyclable Multifunctional Magnetic Mesoporous Silica Nanocomposite for Ratiometric Detection, Rapid Adsorption, and Efficient Removal of Hg(II)

Yanyan Wang,Meiyao Tang,He Shen,Guangbo Che,Yu Qiao,Bo Liu,Li Wang

In this paper, multifunctional inorganic–organic nanocomposites were fabricated through encapsulating CdTe quantum dots and Rhodamine 6G-deprived receptor into the nonporous and mesoporous shell of the magnetic mesoporous silica nanocomposites. The resultant nanomaterials display an obvious core–shell structure, superparamagnetic property, ordered mesoporous characteristics, and highly selective, sensitive, and regenerative ratiometric fluorescent sensing performance for determination of Hg2+. A good linearity is obtained between IRh6G/IQDs and Hg2+ concentration (0.7 to 90 × 10–8 mol·L–1), exhibiting a detection limit as low as 2.5 × 10–9 mol·L–1. Moreover, the multifunctional nanocomposites possess acceptable Hg2+ adsorption capacity and can be simply separated by magnet. Real water sample assays further verified its good mercury ion analysis and removal ability. Our results reveal that high sensitivity, selectivity, rapid adsorption, efficient removal ability, and good reusability as well as better accuracy can be simultaneously achieved by combining magnetic mesoporous silica nanocomposite with ratiometric fluorescence sensing properties than the traditional intensity-based fluorescence methods. This recyclable multifunctional hybrid nanostructure may have great potential for Hg2+ detection and removal in environmental, biological, and toxicological areas.

Disposable Faraday cage-type aptasensor for ultrasensitive determination of sub-picomolar Hg(II) via fast scan voltammetry

Qi Wang,Tao Wang,Han Lin,Weiqiang Meng,Chunfeng Zhang,Pingru Cai,Tingting Hao,Yangbo Wu,Zhiyong Guo

ABSTRACT A disposable Faraday cage-type aptasensor for ultrasensitive determination of sub-picomolar Hg(II) was developed based on fast scan voltammetry (FSV). Signal unit [email protected] was designed, in which aminoferrocene (AFc) is the signal label, gold nanoparticles (AuNPs) improve the conductivity of rGO and combine DNA through Au-S bond, DNA could selectively capture Hg(II) with DNA3 through the formation of thymine-Hg(II)-thymine (T-Hg(II)-T) complex, and rGO provides the basis for loading above functional components. In presence of Hg(II), the signal unit could be immobilized on the disposable electrode through T-Hg(II)-T mismatch to build a Faraday cage-type aptasensor, and the scan rate of 400 V/s was used by FSV, resulting in ultrasensitive determination of Hg(II) in concentration range from 0.1 μmol/L to 0.1 pmol/L with a limit of detection (LOD) 0.03 pmol/L. The sensitivity is greatly improved due to the following points: a large number of signal labels AFc are immobilized, conductive rGO allows all AFc immobilized to participate in the electrode reaction, and a high scan rate is used. Satisfied stability, selectivity and accuracy were obtained. Thus, this proposed disposable Faraday cage-type aptasensor provides a new path to ultrasensitive on-site rapid determination of Hg(II) or analog heavy metal ions.

Adsorption behavior and mechanism of Hg (II) on a porous core-shell copper hydroxy sulfate@MOF composite

Ling Zhang,Jinghua Zhang,Xinglin Li,Cuijie Wang,Ajuan Yu,Shusheng Zhang,Gangfeng Ouyang,Yuanyuan Cui

Herein, a porous core-shell copper hydroxy sulfate@metal-organic framework decorated by 2,5-dimercapto-1,3,4-thiadiazol (DMTZ) was synthesized via a facile self-template strategy for the capture of Hg 2+ . The strategy of assembling MOF shell on copper hydroxy sulfate (CHS) core avoided the self-nucleation of MOF(Cu 3 (BTC) 2 ) in the solution and complex multistep procedures by means of in situ transformation the metal source CHS into well-defined Cu 3 (BTC) 2 crystal. The structure and properties of the DMTZ modified CHS@Cu 3 (BTC) 2 (CHS@Cu 3 (BTC) 2 -DMTZ) was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA) and N 2 sorption–desorption isotherms (BET). The adsorption behavior followed Langmuir adsorption model and the maximum adsorption capacities for the removal of Hg 2+ was up to 627.6 mg g −1 . 99.96% Hg 2+ was rapidly captured by CHS@Cu 3 (BTC) 2 -DMTZ within 10 min from 40 mg L -1 to 0.014 mg L -1 . Meanwhile, not only X-ray photoelectron spectroscopy (XPS) but also Raman spectra verified the selective and strong interaction between Hg 2+ and thiol/nitrogen-containing functional groups of DMTZ on CHS@Cu 3 (BTC) 2 -DMTZ. These results manifested that this novel thiol-functionalized MOF adsorbent had superior adsorption capacity and selective for Hg 2+ .

CdTe quantum dot-based fluorescent probes for selective detection of Hg (II): The effect of particle size

Jian Zhu,Zhu-Jun Zhao,Jian-Jun Li,Jun-Wu Zhao

Mercury ions-induced fluorescence quenching properties of CdTe quantum dots (QDs) have been studied using the fluorescence spectroscopic techniques. By using the hydrothermal method , the CdTe QDs with different particles sizes from 1.98 to 3.68   nm have been prepared, and the corresponding fluorescence emission wavelength is changed from 518 to 620   nm. The fluorescence of QDs is enhanced after linking Bovine serum albumin (BSA) onto the surface of the QDs. Experimental results show that the fluorescence intensity of BSA-coated CdTe QDs could be effectively quenched when Hg 2   + react with BSA-coated CdTe QDs. Interestingly, both the sensing sensitivity and selectivity of this fluorescence probe could be improved when the particle size of the QDs decreases. Thus the BSA-coated CdTe QDs with green fluorescence emission have better advantages than the BSA-coated CdTe QDs with red fluorescence for Hg 2   + detection. Interference experiment results indicate that the influence from other metal ions could be neglected in the detection, and the Hg 2   + could be specifically detected. By using this BSA-coated CdTe QDs-based fluorescence probe, the Hg 2   + could be detected with an ultra-low detection limit of nanomole level, and the linear range spans a scope from 0.001 to 1   μmol/L.

Critical Addition Point-Based Trace Sensing of Hg²+ Through Surface Plasma Polaritons Properties Analysis of Ag Nanoparticles

Xia Zhang,Yu-Ying Wang,Ya-Nan Xu,Meng-Xiao Xu,Hua-Ling Zhang,Guan-Xi Li