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This work reported a simple and ultrasensitive label-free method for the detection of hepatitis B virus (HBV) DNA by combining hyperbranched rolling circle amplification (HRCA) with dual-mode detection by inductively coupled plasma mass spectrometry (ICP-MS) and fluorescence using ruthenium complex [Ru(bpy)2dppz]2+ (bpy = 2,2'-bipyridine, dppz = dipyrido [3,2-a:2',3'-c] phenazine) as a dual functional probe. An HBV DNA-initiated HRCA system was designed to realize the highly efficient amplification of HBV DNA with the generation of a mass of dsDNA. Also, the [Ru(bpy)2dppz]2+ probe was then added to intercalate into the dsDNA products, resulting in strong fluorescence recovery of the probe for fluorescence detection. Meanwhile, using a biotin-modified primer in HRCA, the dsDNA-[Ru(bpy)2dppz]2+ complexes could be captured by the avidin-coated 96-well plates, and the captured [Ru(bpy)2dppz]2+ probe was later desorbed by acid for ICP-MS detection. The linear range of the proposed method was 3.5-200 amol L-1 and the limit of detection (LOD) was 1 amol L-1 for ICP-MS detection, while the linear range was 20-500 amol L-1 and the LOD was 9.6 amol L-1 for fluorescence detection. The developed method was applied to human serum sample analysis, and the analytical results coincided very well with those obtained by the real-time polymerase chain reaction (PCR) method. The developed dual-mode label-free detection method was ultrasensitive, simple, and accurate, showing great potential for therapeutic monitoring of HBV infection.

The loop heat pipe is a passive high-efficiency two-phase transfer device. To study the effects of the liquid and vapor line lengths on the performance of ethane loop heat pipe (ELHP), a performance test system has been set up based on a pulse tube refrigerator (PTR). The lengths of liquid line (LL) and vapor line (VL) of the ELHP are changed in this test system. The LL length is set as 180 mm, 500 mm, 800 mm, 1100 mm and 1500 mm, respectively, when the VL length is 500 mm. In addition, the VL length is set as 800 mm, 1100 mm, and 1500 mm, respectively, as the LL length is 500 mm. The thermal performances of ELHP including startup performance, thermal resistance and temperature difference are investigated in detail under 170 ~ 240 K temperature regions. The experiment results show that the lengths of LL have an important effect on the startup performance when the heat load (HL) of the ELHP is 0 W. The shorter the LL length is, the easier the startup is at 0 W HL. When the LL length is longer, the ELHP is more stable and the temperature oscillation is smaller. The effect of the VL length on the ELHP startup performance is the same as that of the LL length. Due to the thermophysical properties of ethane, the ELHP in the 240 K temperature region has the best performance.

It has been well established that the early-stage interactions of nanoparticles with cells are governed by the extracellular protein corona. However, after entering into the cells, the evolving protein corona is the key to subsequent processing of nanoparticles by cells. To identify the protein corona around intracellular nanoparticles, it is essential to maintain its original compositions during cell treatment. Herein, we develop a paraformaldehyde (PFA) cross-linking strategy to stabilize corona compositions when extracting protein coronas from cells, providing original information on protein coronas around intercellular gold nanoparticles (AuNPs). The stability of the protein corona after PFA cross-linking was carefully investigated with several characterization methods, and the results demonstrate that PFA cross-linking successfully prevents the dissociation and exchange of corona proteins. Then the recovered intracellular protein corona around AuNPs from living HepG2 cells with a PFA cross-linking strategy was subjected to nanoHPLC-MS/MS for proteomic analysis. It was found that the compositions of intracellular protein coronas are dominated by cell-derived proteins and undergo significant variation of protein species and amounts over time during internalization. Time-resolved analysis provides relevant proteins involved in nanoparticle cellular uptake and transportation, indicating that AuNPs are endocytosed mainly by a clathrin-mediated uptake mechanism and directed into an endolysosomal pathway toward their final destination. Such proteomic-based results are verified by pharmacological inhibition and TEM imaging analysis. This work provides a universal strategy to study compositions of protein corona around intercellular nanoparticles and could be a footstone to link the formation of protein corona around nanoparticles to their biological function in cells.

The difficulty in achieving high removal efficiency for contaminants in textile wastewater over a wide range of pH impedes the progress of its treatment technique greatly. Herein, a facile and sustainable strategy was adopted for constructing magnetic ordered mesoporous polymers (M-OMPs) without the assistance of organic solvent and catalyst. The prepared M-OMPs were endowed with high special surface area and good superparamagnetism simultaneously, and exhibited high removal efficiency (>99%) for Methylene Blue (MB) within a short time (10 min) at a concentration of 50 mg/L. What's more, high removal efficiency was achieved over a wide range of pH 2-12 and the adsorption capacity for MB on M-OMPs was substantially retained even after 5 adsorption-desorption cycles, further demonstrating the application potential of M-OMPs in the decontamination of textile wastewater.

A novel sulfur-containing functional core–shell magnetic porous organic polymer (Fe3O4@BD-TpMA-S-SH MOP) was synthesized as a magnetic solid-phase extraction (MSPE) sorbent for mercury speciation followed by high-performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) detection. The prepared Fe3O4@BD-TpMA-S-SH MOP possessed rich active adsorption sites (S: 25 wt%), high magnetism (39.2 emu g−1) and high adsorption capacity (636, 656, 649 and 366 mg g−1 for Hg2+, methylmercury (MeHg+), ethylmercury (EtHg+) and phenylmercury (PhHg+), respectively). Under the optimal conditions, the limit of detection (LOD) of the developed MSPE-HPLC-ICP-MS method was 0.43, 0.55, 0.69 and 1.1 ng L−1 for Hg2+, MeHg+, EtHg+ and PhHg+, respectively, with a high enrichment factor (EF) in the range of 346–383-fold. The accuracy of the method was validated, and it was successfully applied for trace/ultratrace mercury speciation in environmental water and fish samples. The developed method has high sensitivity, low LOD, high EF, fast adsorption/desorption dynamics and good matrix resistance ability, showing great applicability in real sample analysis with complex sample matrices.

Adenosine triphosphate (ATP), as a high-energy phosphate compound that stores and releases energy in living cells, has an irreplaceable role in many physiological processes and maintenance of biological functions, and can be used as an indicator of many diseases. In this work, a composite nanoprobe, silver nanocluster (AgNC) @ molybdenum disulfide (MoS2), was designed to achieve in situ fluorescence imaging and quantitative analysis of intracellular ATP in HeLa cells by fluorescence spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). The probe was constructed based on the adsorption of DNA-AgNCs by MoS2 nanosheets, and the DNA-AgNCs were prepared with the ATP aptamer as a template, whose fluorescence was initially quenched by MoS2. When the probe was incubated into the cells, intracellular ATP recognized the aptamer sequence and caused the DNA-AgNCs to fall off the MoS2 nanosheets, resulting in fluorescence recovery. Here, AgNCs not only acted as a fluorescence label for imaging, but also as an element tag for quantitative analysis of intracellular ATP with the detection of 107Ag by ICP-MS. The ATP in HeLa cells detected by this method was 24.6 ± 1.7 nmol L−1, which was in good agreement with the test result of the ATP test kit (20.4 ± 0.8 nmol L−1). The proposed method has potential application in medical clinical diagnosis and evaluation of the body’s metabolic level via fluorescence imaging and ICP-MS detection of intracellular ATP.

Because of the growing interest in bis-MPA dendrimers and hyperbranched polymers, a linear, polyester equivalent is of great importance in understanding how this commercially viable family of branc...

A spiral stir bar was proposed by using stainless steel spring as the extraction phase carrier to avoid the extraction phase friction and increase the amount of extraction phase for improving extraction efficiency. The extraction phase is filled in the cavity of the spring, resulting in a larger amount of the extraction phase than that conventionally coated on glass stir bar or stainless steel wire. Polyaniline-polydimethylsiloxane sol-gel packed spiral stir bar was prepared and evaluated for the extraction of five estrogens. The prepared spiral stir bar presented good extraction efficiency/preparation reproducibility and long lifetime (more than 150 reused times) for target estrogens. Based on it, a method of spiral stir bar sorptive extraction combined with high performance liquid chromatography coupled with ultra-violet detection was developed for the analysis of trace estrogens in environmental and food samples. The detection limit for five estrogens was 0.11-.31 µg/L, with the enrichment factors of 83.0-118-fold (maximal enrichment factor: 200-fold). The reproducibility evaluated with each estrogen of 5 µg/L (n = 5) was 5.8-8.9%. The method was successfully applied for the determination of estrogens in environmental water and animal-derived food samples.

The separation of oil-water mixtures has attracted widespread attention for addressing increased oil spillage and oil-polluted water. In this study, a novel and low-cost oil-water separation coatin...

Cancer immunotherapy provides an effective way to deal with cancer. Although immunotherapy strategies have shown encouraging therapeutic effects, the inherent limitations of immunotherapy, such as multiple tumor immune evasion methods, low response rate, and systemic toxicity, still hinder its clinical applications. In recent decades, nanomaterials have been considered promising in cancer immunotherapy since they can realize targeted delivery and interact with the immune system to induce or enhance the antitumor immune responses. Among them, organic/inorganic nanocomposites are ideal candidates for cancer immunotherapy since they could combine the advantages of both organic and inorganic components. Multifunctional organic/inorganic nanocomposites could help overcome the shortcomings of current cancer immunotherapy, and realize the combination of immunotherapy and other therapeutic strategies with synergistic antitumor effects. Herein, we review the recent progress of organic/inorganic nanocomposites designed for cancer immunotherapy. The immunotherapy strategies of nanocomposites are summarized from the perspective of achieving immune enhancement. The challenges of nanocomposites in cancer immunotherapy are also discussed.

The carbon nanofibers and molybdenum disulfide (CNF-MoS2) nanohybrid material was fabricated and incorporated into epoxy resin to form the nanocomposite coating. Firstly, microstructure observation shows that each CNF was uniformly wrapped up with MoS2 nanosheets, and the nanohybrids were well dispersed in the coating. Then, nanoindentation experiments were carried out to explore the effect of the CNF-MoS2 nanohybrids on the mechanical properties of the epoxy resin coating. The results demonstrate that elastic modulus, hardness and creep deformation resistance of the CNF-MoS2 epoxy resin coating are greatly increased in comparison with both pure epoxy resin and MoS2 epoxy resin coatings. Finally, the underlying mechanism of high-performance tribological behavior of the nanocomposites is analyzed accordingly. It can be concluded that the wrapped structure with MoS2 sheets growing on the surface of CNF increases the contact area and reduces the friction coefficient of the composite coating, while the wear resistance of the nanocomposite coating is also greatly improved due to the superior high hardness of CNF.

Information on the risk of exposure to cerium oxide (CeO2) nanoparticles (NPs) is limited. To assess risk, we must know where and how such NPs are distributed to the body after exposure, both short- and long-term. In this work, an integrated approach of quantitative LA-ICP-MS bioimaging and fractionation was employed to study the translocation and transformation of CeO2 and Ce3+ in mouse spleen and liver. The complementary information retrieved by the two techniques above on the accumulation of Ce and dissolution/aggregation were found consistent. In brief, a detailed fine scanning of a region of interest in the organ was performed after fast-screening at low spatial resolution. In the spleen, after short-term high-dose exposure, CeO2 NPs was found mainly in the marginal zone and caused an up-regulation of Zn in the white pulp. After long-term low-dose exposure, CeO2 was found in the marginal zone and white pulp. In the liver, CeO2 NPs were mainly distributed in the Kupffer cells and lobule periphery. The high spatial resolution LA maps of HE this enabled an estimation of Ce content in Kupffer cells. Furthermore, fractionation by ultrafiltration was also employed to differentiate the ionic and NP species in the organs. This fractionation showed aggregation of Ce ions in spleen, supporting the LA-ICP-MS results. Transmission electron microscopy revealed that long-term CeO2 exposure triggered an immune response to infection in the spleen and confirmed the differential deposition of Ce in the marginal zone. The integrated analyses based on ICP-MS together with histology and TEM investigation suggests that long-term low doses of CeO2 NPs may cause toxicity in the liver and impair functions of the immune system.

Clay, which is a well-stocked mineral, has often been applied to colorful coatings. Sepiolite is a kind of clay that has excellent properties but has not being reported as a color paint. In this study, a colored paint composed of sepiolite, cationic dye, and organosilanes was sprayed with epoxy resin to form a colorful superhydrophobic coating. The low surface energy of organosilane and the micro-nano microstructure of the coating can form bubbles between the solid and liquid, endowing the coating with good water repellency and with a self-cleaning property. In addition, for aqueous solutions with pH ranging from 1 to 13, the contact angle (CA) of the coating remained greater than 150°. The chemical stability of the coating was very good and did not fade, even after immersion in 1 M NaOH or HCl solution for 24 h. The scratch test on the coating did not destroy the superhydrophobicity of the coating. Additionally, the coating had good mechanical durability, and its CA was still greater than 150° after 50 times of tape test.

Transparent superoleophobic surfaces have attracted a great deal of attention due to their broad applications in daily use. But it has been proven that obtaining transparency and superoleophobicity simultaneously is challenging. Here, we report a one-step spraying method to prepare a robust transparent superoleophobic coating using SiO2@fluorinated polysiloxane, which derived through a sol–gel process of fumed SiO2 with tetraethylorthosilicate and perfluorooctyltrichlorosilane. The obtained coating exhibited high transmittance (above 82.3% for wavelength range 400–800 nm) and outstanding superoleophobicity to low surface tension liquids with the contact angles greater than 150° and sliding angles lower than 10°. The influence of SiO2 concentration and spray layer on the transmittance and superoleophobicity of coatings was also investigated. Results showed proper surface roughness and low surface energy are two main factors accounting for superoleophobicity. And to achieve highly transmittance, surface roughness of coating should be less than one-quarter of visible wavelength. More importantly, the superoleophobic coating demonstrated excellent mechanical and chemical stability, which confirmed through a series of experiments such as thermal treating at 300 °C, repelling corrosive liquid droplets, and high-speed sand impact. We envision our findings have a promising development space due to its simple preparation process and outstanding performance.

Magnetic porous organic polymers (MOPs) were synthesized by a simple azo reaction, with 1,3,5-tris (4-aminophenoxy) benzene and 1,3,5-trihydroxybenzene as the monomers, and Fe3O4@SiO2 as the core. The preparation process was mild, green and environmental-friendly, avoiding the use of high temperature, metal catalysis and harmful organic reagent. The obtained MOPs were characterized in terms of morphology, pore structure, and magnetism; they exhibited high surface area, good stability/dispersibility, and excellent extraction performance for interest triazole fungicides (TFs). With the prepared MOPs as adsorbent, a method of magnetic solid phase extraction-gas chromatography-flame ionization detection (MSPE-GC-FID) was proposed for the analysis of target TFs in vegetables. After the vegetable samples were chopped and homogenized, acetonitrile was added for ultrasonic extraction, and the extract was diluted for subsequent MSPE process. Different operating conditions affecting the extraction efficiency of TFs, such as extraction time, pH, ionic strength, adsorbent dosage, and volume of sample as well as eluent were carefully optimized. Under the optimized experimental conditions, quantitative extraction could be achieved for target TFs (extraction efficiency of 84.5–90.3%), and the limits of detection were in the rage of 0.12–0.19 μg/L, which is the lowest among the reported GC-FID methods for target TFs presently. The linear range of the method for five TFs was 0.5–200 μg/L with the reproducibility of 2.6–6.8% (n = 7, c = 2 μg/L). The method was assessed by the analysis of target TFs in vegetables, and the recoveries for the spiked cucumber and cabbage were 86.9–117% and 84.7–114% (spiking levels of 80, 400 and 800 μg/kg), respectively, indicating that the matrix effect was negligible in the proposed MSPE procedure. The results show that the developed method of MSPE-GC-FID with MOPs as adsorbent is efficient for the analysis of trace TFs in vegetables.

Graphene oxide (GO) with abundant oxygen functional groups has been widely studied as friction-reduction additive in lubricating oil or directly as solid lubricant. However, the lubrication mechanisms of these groups in solid GO lubricants have not been well revealed yet. Herein, we report a new strategy to prepare hydroxyl-carboxyl-terminated GO, hydroxyl-terminated GO, less-hydroxyl-terminated GO, and reduced GO (rGO), and then employ them as a frictional research model to address this concern. The results reveal that a little amount of water confined in GO layers dominates the interlayer shearing resistance by confining hydrogen-bond interaction. The strongest confinement effect to hydrogen-bond is achieved in hydroxyl-terminated GO, leading to the lowest shearing resistance between GO layers and then the enhanced friction performances. This finding first reveals the synergistic lubrication mechanism of oxygen functional groups and confined interlayer water molecules, providing us a new design view to fabricate superior graphene-based solid lubrication materials.

Cellular uptake of Au NPs is the premise for their application in drug delivery, cell/tissue imaging and quantitation analysis of biomarkers in the cells. However, conventional methods for cell analysis may lead to the loss of important information from abnormal or atypical cells in the cell population. In this work, with 15, 30 and 60 nm Au NPs@citric acid and Au NPs@DNA as model materials, the cellular uptake of Au NPs in single HeLa cells is studied by using an on-line droplet chip inductively coupled plasma mass spectrometry hyphenated technique. It is found that the average amount of Au uptake for Au NPs@citric acid is higher than that for Au NPs@DNA at high incubation concentrations. The distribution of the number of uptaken Au NPs in single HeLa cells shows a great difference when HeLa cells are incubated with different Au NPs. The percentage of cells uptaking Au NPs in the cell population also reveals a difference in cellular uptake between Au NPs@citric acid and Au NPs@DNA at the single-cell level. To explain the abovementioned phenomenon, the endocytosis mechanisms of Au NPs are investigated. Clathrin-mediated endocytosis is found to be the major internalization pathway for 15 and 30 nm Au NPs@DNA.

Therapeutic drug monitoring is central to optimize therapeutic efficacy and minimize adverse events; however, the pharmacokinetics and pharmacodynamics of most drugs differ greatly among individuals. Evaluation of the therapeutic response is in urgent need to help clinician predict the clinical dose of drug. Herein, we described an analytical assay using gold nanocluster (AuNC)-decorated metal-organic frameworks (MOFs) for targeted drug delivery and monitoring pharmacodynamics, giving attractive options for studying individualized therapy. The camptothecin (Cam) anticancer drug was caged in the NH

To well play the synergy between CNF and MoS2, the hybrid of CNF/MoS2 core-shell structure were successfully prepared via a one-step hydrothermal method. And the as-prepared CNF/MoS2 hybrid showed both excellent lubricity and reinforcing effects to enhance EP composite coatings. Compared with EP and other single filler reinforced composite coatings, EP-CNF/MoS2 had better anti-friction and anti-wear properties, and the friction coefficient and wear rate were only 0.075 and 8.6 × 10−5 mm3/Nm, respectively. This was mainly attributed to the synergistic effect between CNF and uniformly loaded MoS2 as well as the good interfacial adhesion between CNF/MoS2 and EP matrix. Moreover, two feed ratios of CNF and MoS2 precursors were designed to investigate the relationship between the morphology of the synthesized heterostructure and the lubricity. And the EP-CNF/MoS2-3 possessed much better friction and wear properties than EP-CNF/MoS2-1 and EP-CNF/MoS2-2. All these suggested that CNF/MoS2 core-shell structure was a promising additive applied in tribology.

Accurate identification and quantification of trace elements and their species in cells is an important prerequisite for the exploration of their physiological function and related mechanisms of pr...

Time-resolved (TRA)-ICPMS has become a booming subfield of single-cell analysis tools in recent years, while generation of single cells remains the major challenge. Microfluidic devices reveal their great capability and potential in encapsulation of single cells into water droplets. However, current strategies to pinch off droplets require a specific oil phase, which is not compatible to conventional ICPMS and makes the signal of cells in the water phase susceptible. Herein, we built a 3D water-in-gas microfluidic device (3D W/G MFD) with commercially available components, producing single cell droplet enclosed by argon gas. By simply tuning the flow rate of gas and water, the droplets were generated to encapsulate single cells, which significantly reduced the probability of the single signal coming from multiple cells by 1 or 2 orders of magnitude compared to direct injection. The developed oil-free 3D W/G MFD was more friendly to online coupling with TRA-ICPMS than water-in-oil devices. The effect of Cd2+ on HepG2 cells was studied by single cell detecting total Zn with 3D W/G MFD-TRA-ICPMS, and the variation of labile Zn was explored by flow cytometry with an N-(6-methoxy-8-quinolyl)-p-toluenesulfonamide probe. To the best of our knowledge, this work pioneered the exploration of variation in cellular metal content and speciation at the single-cell level, compensating for the deficiency of speciation analysis based on TRA-ICPMS and providing new insights into exploring the complexity of biology.

Recent progress of stir bar sorptive extraction (SBSE) in the past six years is reviewed. The preparation methods including electrodeposition, self-assembly, solvent exchange, physical magnetic adsorption and electrostatic spinning, for the coated stir bar are summarized and compared, specifically for a specific material for coatings fabrication, e.g., carbon-based materials and metal organic frameworks. The emerging materials (e.g., graphene, graphene oxide, carbon nanotubes, monolith, metal-organic frameworks and porous organic polymers) applied for coated stir bar fabrication are one of the focus of this review, along with their respective advantages in extraction process and application in trace analysis. The development and application of extraction apparatus of SBSE are also involved. Based on these information, the development status and prospects of SBSE as an efficient sample pretreatment technique in real sample analysis are discussed.

Inductively coupled plasma mass spectrometry (ICP-MS) combined with element tags has been well designed and extensively applied in cell enumeration. It possesses superior quantitative capability, strong resistance to matrix interference, multiplex detection capability but destructive characteristic. Herein, we constructed an ICP-MS based multifunctional platform for capture, nondestructive enumeration, and release of circulating tumor cells (CTCs). Aptamer on capture probe recognized Mucin 1 (MUC1) on membrane of MCF-7 cells specifically, thus the cells were captured by probe and the Initiator originally hybridized with Aptamer was substituted by MUC1 and released into solution. Then the released Initiator was separated from the captured cells and hybridized with Tb labeled Substrate on detection probe to release a large amount of nicked Tb fragments through the nicking endonuclease assisted amplification for subsequent ICP-MS detection. Meanwhile, cells captured by probe were released by nuclease digestion for further reculture. Such a strategy effectively avoids CTCs destruction resulted from ICP-MS enumeration, increases the detection sensitivity of ICP-MS by involving nicking endonuclease assisted amplification, and realizes cell recovery for further analysis. A limit of detection of 87 MCF-7 cells and a linear range of 250-10 000 MCF-7 cells were realized for ICP-MS enumeration. A cell recovery of 52.7% (with capture and release efficiency of 63.9 and 82.5%, respectively) and a viability of 74.3% were obtained, meanwhile the released cells exhibited strong proliferation ability. This multifunctional platform for CTCs capture, enumeration, and release has great applicable potential in early diagnosis and individual treatment for cancer.

Ti (IV) modified vinyl phosphate magnetic nanoparticles (Fe3 O4 @SiO2 @KH570-PO4 -Ti (IV)) was prepared for simultaneous extraction of multiple arsenic species, followed by high performance liquid chromatography (HPLC) - inductively coupled plasma mass spectrometry (ICP-MS) analysis. Inorganic arsenic (iAs), dimethyl arsenic acid (DMA), monomethyl arsenic acid (MMA), p-amino phenyl arsenic acid (p-ASA), 4-hdroxyphenylarsenic acid (4-OH), phenyl arsenic acid (PAA) and 3-nitro-4-hydroxyphenylarsenic acid (ROX) were investigated as interest analytes. It was found that they were quantitatively adsorbed on Fe3 O4 @SiO2 @KH570-PO4 -Ti (IV) at pH 5, and desorbed completely with 0.1 mol/L sodium hydroxide solution. Enrichment factor of 100-fold was obtained by consuming 100 mL sample solution. Under the optimal conditions, the method combining MSPE with HPLC-ICP-MS presented a linear range of 1-5000 ng/L for seven arsenic species. The limits of detection were 0.39, 0.60, 0.23, 1.85, 0.54, 0.48 and 0.84 ng/L for DMA, MMA, p-ASA, iAs, 4-OH, PAA, ROX, with the relative standard deviations (c = 10 ng/L, n = 7) of 3.6, 3.9, 5.5, 12.4, 6.1, 5.8, 5.0, respectively. The accuracy of the method was validated by analyzing BCR 627 Tuna fish. The application potential of the method was further evaluated by chicken muscle and liver samples. No target arsenic species were detected in these samples, and good recoveries (80.6-123%) were obtained for the spiked samples at low, medium and high concentration levels. This article is protected by copyright. All rights reserved.

In this work, magnetic nanoporous carbons (MNPCs) based on Zn/Co-MOFs was synthesized via a facial one-step carbonization method. The prepared MNPCs exhibited high specific surface areas, good chemical stability and high extraction efficiency for interest organophosphorus pesticides (OPPs). The good extraction performance of the MNPCs for interest OPPs can be primarily attributed to π-π interaction and hydrophobic interaction between MNPCs and OPPs. Based on it, MNPCs-based MSPE-GC-FPD method was established for the quantification of five OPPs in fruit samples. The main experimental conditions for MSPE of five target OPPs were investigated systematically and optimized, such as the desorption solvent and volume, extracted volume, ionic strength, extraction time and desorption time. Under the optimal conditions, the limits of detection (LODs, S/N = 3) were found to be in the range of 0.018 (ethion) -0.045 (malathion) μg/L. The linearity was 0.05-100 μg/L for phorate, diazinon, ethion and 0.1-100 μg/L for malathion, fenthion respectively. The reproducibility of the method was in the range of 3.5-9.7%. The recovery experiments were carried out by spiking target OPPs at three concentration levels to validate the accuracy of the proposed method, and the recoveries for target OPPs were 84-116%. The results show that the proposed method in this work can be successfully used to analyze OPPs residue in fruit sample.

In order to comprehensively reflect the cigarette quality, a method combining direct injection of diluted sample with high sensitive high-performance liquid chromatography (HPLC)- electrospray (ESI)- quadrupole (Q)- time of flight (TOF)- tandem mass spectrometry (MS/MS) was developed for the identification of major components of cigarette essences (jujube and mulberry extracts). Based on the observed relative molecular mass, MS/MS fragmentation behavior, MS/MS database and related literatures, the components of the jujube extract and mulberry extract were identified. The result shows that the composition of jujube extract and mulberry extract has some similarity. They all mainly contain amino acids, free amino compounds and Maillard reaction products, which are the main constituents of a cigarette essence.

A novel ternary hybrid of carbon nanotubes/graphene oxide/MoS2 was prepared via hydrothermal method, and its microstructure, phase composition, and enhancement effect on the tribological properties of epoxy were investigated systematically. Results revealed EP-CNTs/GO/MoS2 possessed the lowest friction coefficient and wear rate than EP and its other composite coatings reinforced by single filler or binary hybrids. In particular, its friction coefficient and wear rate were 0.042 and 3.44 × 10−5 mm3/Nm, respectively, which were reduced by up to 90% and 95% compared to those of pure-EP. And this was mainly attributed to uniform dispersion of CNTs, GO, MoS2 in CNTs/GO/MoS2 hybrid, and load-carrying capacity of CNTs and GO, self-lubricating effect of MoS2, as well as formation of transfer film onto counterpart surface.

The analysis of telomerase is of great significance for the study and diagnosis of cancer. In this work, a dual-functional Au NP probe for the quantification and imaging of intracellular telomerase was prepared. The probe contained an elemental tag (1,4,7,10-tetraazacyclododecane-1,4,7-tris-acetic acid (Tb-DOTA)) for accurate quantification using inductively coupled plasma mass spectrometry (ICP-MS) and a fluorescent tag (FAM) which constructed the fluorescence resonance energy transfer (FRET) system with Au NPs for fluorescence imaging. After the probe entered into the Hela cells, the telomerase primer was extended with TTAGGG repeats in the presence of the intracellular telomerase, resulting in turning on the fluorescence of FAM and releasing the Tb-DOTA. Thus, the intracellular telomerase could be in situ visualized by the released FAM with fluorescence imaging and quantified by the released Tb-DOTA with ICP-MS detection. The average amount of telomerase in one Hela cell was quantified to be 3.1 × 10−11 IU. The proposed method was demonstrated with good potential in the study of telomerase and the cancer diagnosis, providing a new strategy for the analysis of intracellular biomarkers by ICP-MS.

Arsenite (As(III)) has been considered as a human carcinogen associated with many human cancers especially skin cancer. Elucidation of the transformed species of As(III) during its metabolism in cells is beneficial for evaluation of its bioeffect. In this work, a hyphenated method of reversed phase ion pair high performance liquid chromatography - inductively coupled plasma mass spectrometry (RP-IP-HPLC-ICP-MS) equipped with collision/reaction cell technology (CCT) was developed for speciation of As(III) and its metabolites (arsenate [As(V)], monomethylarsonic acid [MMA(V)], and dimethylarsinic acid [DMA(V)]) in SCC-7 cells. The developed analytical method exhibits low limits of detection for interest arsenic species in the range of 14-27 ng/L and wide linear range up to four orders of magnitude, providing a sensitive tool for arsenic metabolites analysis and further understanding the metabolism of As(III) in SCC-7 cells. The effect of exposure time, exposure concentrations and elimination time on the arsenic species and total arsenic in SCC-7 cells incubated by As(III) were systematically studied. At low exposure concentrations (5 μM), large proportion of intracellular As(III) transformed to methylated metabolites, and the final methylated metabolite DMA(V), which could not be completely removed from the cells in the elimination process, is considered to play as the primary carcinogen. While at high exposure concentrations (5 μM), most of intracellular As(III) probably bound to biomacromolecules rather than followed biomethylation process, exhibiting different metabolism.

In this work, ethylenediamine modified poly(glycidyl methacrylate-ethylene dimethacrylate)(poly(GMA-EDMA-NH2)) was prepared for highly selective extraction of Se(VI) with high adsorption capacity of 0.825 mg m−1 (530 µm i.d.). Based on it, a novel method of polymer monolithic capillary microextraction (CME) on-line coupling with inductively coupled plasma-mass spectrometry (ICP-MS) was developed for the determination of inorganic selenium species (Se(IV)/Se(VI)) in natural waters. Under the optimized conditions, the analytical performance of the proposed on-line CME-ICP-MS method was evaluated for Se(VI). The limit of detection for Se(VI) was 14.2 ng L−1, and the enrichment factor was 50-fold with the sample throughput of 5 h−1. For Se(IV), the concentration was obtained by subtracting Se(VI) from the total Se(VI) obtained by the proposed method after oxidation of Se(IV) to Se(VI). The accuracy of the method was validated by the analysis of a Certified Reference Materials of GBW(E)080395. The proposed method was applied for the analysis of inorganic selenium species in natural waters with good recoveries. The developed method of monolithic CME-ICP-MS is sensitive, simple and rapid for the analysis of inorganic selenium species in natural waters.

A melamine-based porous organic polymer (mPMF) was synthesized as solid phase extraction (SPE) adsorbent for inline SPE-high performance liquid chromatography (HPLC)-ultraviolet detector (UV) analysis of five phytohormones. Melamine contributed to the rich π-electron and N-containing triazine structure for mPMF, which could form π-π interaction and intermolecular hydrogen bond with COOH containing phytohormones. The synthesized mPMF adsorbent shows extremely high extraction efficiency for five target analytes (>80%) including salicylic acid, indole-3-acetic acid, abscisic acid, 2,4-dichlorophenoxyacetic acid and 1-naphthalene acetic acid. The factors affecting extraction of the target phytohormones were investigated and the optimized experimental conditions were established. The linear range was 0.2–100 μg/L with the limits of detection in the range of 0.06–0.11 μg/L for five target phytohormones. The developed method of mPMF-inline-SPE-HPLC-UV was applied for the analysis of trace target phytohormones in tomato and grape juice samples, and the recovery in the range of 83.1–116% and 87.2–121% was obtained for the spiked tomato and grape juice, respectively. This method has the advantages of high sensitivity and good reproducibility, and it has good application potential for the analysis of phytohormones in fruit samples. Moreover, inline analysis avoided the problems of sample pollution and sample loss, and provided a sample throughput of 5/h.

Biomass-derived carbon aerogels with 3D network porous structure show excellent physical properties and exhibit superior application potential. Here, we prepare multifunctional carbon aerogels (MCAs) by carbonization of aerogels composed of typha orientalis fibers. The MCAs feature light mass (5.0 mg cm−3), excellent compressibility (80%), good electrical conductivity (0.18 S cm−1), and very high oil absorption capacity (42–160 g g−1). Because of the excellent superhydrophobic/superoleophilic properties, the MCAs can be used as adsorbent materials to remove free oils in water by various methods. The MCAs can also be applied for efficient separation of surfactant-stabilized water-in-oil emulsions and rapid removal of soluble dyes in oils. Furthermore, the mixtures of multi-emulsions and dyes can be purified with MCAs, which makes MCAs alternative materials for oil purification.

N-doped magnetic porous carbon (N-MPC) is an emerging adsorbent for water pollution control. However, high cost and multisteps procedure make the direct fabrication of N-MPCs difficult until now. Herein, highly dispersed N-MPCs were synthesized by a facial one-pot solid-state pyrolysis strategy. Heating the mixture of ZnO, Co(OH)2, and 2-methylimidazole (HmIm), Zn/Co bimetallic ZIFs formed at the initial stages, being the primary self-template to produce N-MPCs during subsequent high-temperature treatment. By altering the pyrolysis temperature and the molar ratio of ZnO/Co(OH)2 in the precursor, the magnetism, nitrogen content, and surface areas of N-MPCs can be easily controlled. Due to its high special surface areas and the decoration of abundant nitrogen functional groups (pyrrole-N and pyridinic-N), the optimized N-MPC-700-7/3 exhibited a superior adsorption performance for Hg2+ uptake (489 mg g–1). Moreover, the N-MPCs exhibited fast dynamics in adsorption (K2 = 0.47 g mg–1 min–1) and good chemical s...

In this work, poly(1-vinylimidazole-ethyleneglycol dimethacrylate) (poly(VI-EDMA)) monolith coated stir bars were synthesized by one-pot polymerization, and they exhibited higher extraction efficiency and faster extraction dynamics for selected PFAAs than commercial ethylene glycol modified silicone (EG-silicone) and polydimethylsiloxane (PDMS) coated stir bars. Taking eleven PFAAs as target analytes, including C4-C12 perfluoroalkyl carboxylates (PFCAs) and C6, C8 perfluoroalkane sulfonates (PFSAs), a method combining monolith-based stir bar sorptive extraction (SBSE) with high performance liquid chromatography (HPLC) − electrospray tandem mass spectrometry (ESI–MS/MS) was proposed for the determination of multiplex PFAAs in environmental water samples. Under the optimized conditions, low limits of detection (0.06–0.40 ng/L) and wide linear range (0.6–400 ng/L) were obtained for target PFAAs with. The developed method was then applied for the analysis of target PFAAs in environmental water samples, and recoveries of 80.1–117% and 80.3–122% were obtained for target PFAAs in spiked Yangtze River and East Lake water samples respectively.

A switchable hydrophilicity solvent (SHS) based liquid phase microextraction (LPME) method was proposed for the preconcentration of trace Pb (II) and Cd (II) followed by graphite furnace atomic absorption spectrometry (GFAAS) detection. The SHS of protonated triethylamine carbonate (P-TEA-C) was synthesized and applied as the extractant, which is environmentally friendly and low cost. Pb (II) and Cd (II) in ammonium pyrrolidine dithiocarbamate (APDC) complex form was extracted into the triethylamine (TEA) phase by converting P-TEA-C to TEA. The vortex led to the rapid formation of fine droplets of the extractant in the aqueous solution, and enlarged contact surface between both immiscible liquids. The factors affecting the microextraction procedure, including sample pH, APDC concentration, volume of SHS and NaOH, sample volume and matrix effect were investigated. Under the optimal conditions, enrichment factor of 50 was achieved with consumption of 10 mL aqueous sample, and detection limits of 16 and 3.9 ng L−1 were obtained for Pb (II) and Cd (II), respectively. The accuracy of the proposed method was validated by the analysis of Certified Reference Materials of GSBZ50009-88 environmental water, GBW07605 tea and GBW07601(GSH-1) human hair. The method was also successfully applied for determination of Pb (II) and Cd (II) in water, tea and human hair samples.

A method based on ion-pair reversed phase high performance liquid chromatography (HPLC) hyphenated with inductively coupled plasma mass spectrometry (ICP-MS) was developed for arsenic speciation in extract of tree moss. Under the optimal conditions, the limit of detection of eight arsenic species including arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMA), dimethylarsonic acid (DMA), trimethylarsinoxide (TMAO), tetramethylarsonium (Tetra), arsenocholine (AsC) and arsenobetaine (AsB) is between 0.04 and 0.07 ng/mL, with a linear range of 0.2 - 500 ng/mL. Three unknown arsenic species (Unk1, Unk2 and Unk3) and six specific arsenic species (AsIII, AsV, DMA, TMAO, Tetra and AsB) were detected in the extract of tree moss. Unk3 was identified as a kind of arsenosugars (2,3-dihydroxypropyl-5-deoxy-5(dimethylarsenoso)furanoside, arsenosugar X) by electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-qTOF-MS).

Amino-decorated Zr-based magnetic Metal-Organic Frameworks composites (Zr-MFCs) were prepared by a facile and efficient strategy. The nano-sized Fe3O4@SiO2 core (about 15 nm) was coated with a shell of Zr-MOFs (about 5 nm) by means of in-situ growth. And, Fe3O4@SiO2@UiO-66 and its amino derivatives (Fe3O4@SiO2@UiO-66-NH2 and Fe3O4@SiO2@UiO-66-Urea) were successfully prepared by using different precursors. The obtained Zr-MFCs were demonstrated to be efficient adsorbents for metal ions/organic dyes removal from aqueous solution, with high adsorption capacity and fast adsorption kinetics. It was found that the amine-decorated MFCs were highly efficient for metal ions/dyes removal compared to raw MFC-O. Among them, MFC-N exhibited the highest capacity for Pb2+ (102 mg g−1) and methylene blue (128 mg g−1), while MFC-O exhibited the highest capacity for methyl orange (219 mg g−1). Moreover, anionic and cationic dyes could be selectively separated and removed from the mixed solution just by adjusting the solution pH with Zr-MFCs as the adsorbents. And these Zr-MFCs materials can be easily regenerated by desorbing metal ions/organic dyes from the sorbents with appropriate eluents, and the adsorption capacity can be remained unchanged after 6 recycles. The obtained results demonstrated the great application potential of the prepared MFCs as fascinating adsorbents for water treatment.

In this study, poly(1-vinylimidazole) functionalized gold ion imprinted polymer coated magnetic nanoparticles (MNPs@PVIM-Au-IIP) were prepared and characterized. The adsorption behaviors of the prepared MNPs@PVIM-Au-IIP toward gold ions (Au(III)) were studied, it was found that MNPs@PVIM-Au-IIP has good selectivity, high adsorption capacity (185.4 mg g−1) and fast adsorption kinetic for Au(III). Based on it, a new method of ion imprinted magnetic solid phase extraction (II-MSPE) coupled with graphite furnace atomic absorption spectrometry (GFAAS) detection was proposed for the analysis of trace Au(III) in real samples with complicated matrix. Factors affecting MSPE including sample pH, desorption reagent, elution concentration and volume, elution time, sample volume and adsorption time were optimized. With high enrichment factor of 100-fold, the detection limit of the proposed method is 7.9 ng L−1 for Au(III) with the relative standard deviation of 7.4% (c = 50 ng L−1, n = 7). In order to validate the accuracy of the proposed method, the Certified Reference Material of GBW07293 geological sample (platinpalladium ore) was analyzed, and the determined value was in good agreement with the certified value. The proposed II-MSPE-GFAAS method is simple, fast, selective, sensitive and has been successfully applied in the determination of trace Au in ore, sediment, environmental water and human urine samples with satisfactory results.

To overcome the poor mechanical properties of biomass aerogels in oil/water separations, three different freeze-casting methods were used including direct freezing, unidirectional freezing, and bidirectional freezing with sodium alginate (SA) aerogels reinforced with cellulose nanofibrils (CN). After chemical crosslinking and silane modification, compression testing revealed that the SA/CN aerogels with parallel lamellar microstructures prepared by bidirectional freezing exhibited super-elasticity with the minimal energy dissipation of ~ 0.04 in each cycle, a maximum compressive stress of 80.4 kPa, and minimal plastic deformation at ~ 4.15%. Additionally, the water and oil contact angle of the surface of the lamellar SA/CN aerogel was 148.7° and 0°, respectively. By combining the super-elasticity and hydrophobicity/superoleophilicity, the lamella SA/CN aerogels could be reused for the separation of oil/water mixture with oil absorption capacities up to 34 times its weight. Furthermore, the lamellar SA/CN aerogel could continuously separate oil/water mixtures with the assistance of a pump. Therefore, the present study offers a simple and environmentally friendly method for fabrication of super-elastic and hydrophobic/superoleophilic biomass aerogels that are applied to continuous removal of oil from water.

Magnetic metal–organic framework composites (MFCs) were prepared in water at room temperature through a simple, low-cost and green strategy only by employing organic salts as anionic linker sources. Amino-functionalized MFCs (MFC-N) with different amino group contents were successfully prepared by varying the ratio of disodium of 2-aminoterephthalic (NH2-Na2BDC)/terephthalic acid (Na2BDC). The prepared nanoscale MFC-N-X (X represents the percentage of NH2-Na2BDC, i.e., X = 0, 50, and 100) showed high surface area, large pore volume, excellent magnetic response, and good water and thermal stability. Among these prepared MFC-N-X, MFC-N-100 exhibited the highest adsorption capacity of 358 mg g–1 for methylene blue (MB) and 71 mg g–1 for As(V) due to its porous structure and abundant amino groups. The prepared MFC-N-100 was successfully applied to remove MB and As(V) from different water samples (tap water, lake water, and domestic sewage) with a high removal efficiency and a rapid separation of the sorbent f...

In this paper, magnetic mesoporous carbon composites were prepared by calcination of the mixture of magnesium citrate and Fe3O4@SiO2 in an inert atmosphere. A high content of Fe3O4@SiO2 and MgO was in situ embedded in a carbon matrix. After removing the MgO template by diluted acid, the resulting material (Fe3O4@SiO2@mC) was subjected to further H2O2 oxidation treatment. The formed oxygen-containing functional groups on the products provided plenty of active sites for the adsorption of analytes of interest. The obtained composites (Fe3O4@SiO2@mC-H2O2) exhibited a mesoporous structure with a high specific surface area of 731 m2 g–1. The adsorption capacities of Fe3O4@SiO2@mC-H2O2 for Cu(II) and Pb(II) were calculated to be 86.5 and 156 mg g–1, respectively. Under optimal conditions, the adsorption isotherm of Cu(II) and Pb(II) onto Fe3O4@SiO2@mC-H2O2 fitted the Langmuir model and the adsorption kinetic was well-correlated with the pseudo-second-order model. Besides, Fe3O4@SiO2@mC-H2O2 exhibited fast removal dynamics (within less than 1 min) for Cu(II) and Pb(II), demonstrating great application potential in wastewater treatment.

Development of multimodal detection technologies for accurate diagnosis of cancer at early stages is in great demand. In this work, we report a novel approach using an aptamer-based dual-functional probe for rapid, sensitive, and specific counting and visualization of MCF-7 cells by inductively coupled plasma–mass spectrometry (ICP-MS) and fluorescence imaging. The probe consists of a recognition unit of aptamer to catch cancer cells specifically, a fluorescent dye (FAM) moiety for fluorescence resonance energy transfer (FRET)-based “off-on” fluorescence imaging as well as gold nanoparticles (Au NPs) tag for both ICP-MS quantification and fluorescence quenching. Due to the signal amplification effect and low spectral interference of Au NPs in ICP-MS, an excellent linearity and sensitivity were achieved. Accordingly, a limit of detection of 81 MCF-7 cells and a relative standard deviation of 5.6% (800 cells, n = 7) were obtained. The dynamic linear range was 2 × 102 to 1.2 × 104 cells, and the recoveries i...

A novel adsorbent of magnetic graphene oxide (GO) chemically modified by cysteamine hydrochloride (Fe3O4@SiO2/GO-NH2) through thiol-ene click chemistry reaction was synthesized. The prepared Fe3O4@SiO2/GO-NH2 exhibit selective adsorption to As(V) with high adsorption capacity (52.66 mg g−1). Taking Fe3O4@SiO2/GO-NH2 as the adsorbents, a new method of magnetic solid phase extraction (MSPE) combined with graphite furnace atomic absorption spectrometry (GFAAS) was developed in determining trace-level inorganic arsenic species (As(III) and As(V)) in environmental water and bottled water samples. Various experimental parameters affecting the MSPE have been optimized. Under the optimal experimental parameters, the limit of detection of the established method for As(V) was 1.02 ng L−1, the relative standard deviations were 7.9% (intra-day, c = 50 ng L−1, n = 5) and 4.6% (inter-day, c = 50 ng L−1, n = 7), respectively, and the enrichment factor of the method was 392. GBW08666 and GBW08667 (certified reference material) were analyzed to confirm the accuracy of the method, and the results were matched well with the certified values. The established MSPE-GFAAS method was successfully applied in analyzing trace/ultratrace As(III) and As(V) in real water samples.

Exploitation of efficient adsorbent for analyzing mercury species in complex biological samples is still a big challenge. Herein, a MIL-101 covalently bonded and mercapto functionalized capillary monolithic column was prepared by one-step strategy involving simultaneous initiation of thiol-ene click reaction and radical polymerization. It showed improved specific surface area, hierarchical porous structure, rich sulfhydryl groups and high adsorption capacity for mercury species. It was embedded in the microchannel of microfluidic chip for chip-based array monolithic capillary microextraction (CMCME) of mercury species in cells. Methylmercury (MeHg+) and inorganic Hg (Hg2+) could be simultaneously retained on the prepared column and sequentially eluted; both species could also be simultaneously eluted with 4% thiourea in 0.5 mol L-1 HNO3 solution. Based on it, CMCME was combined with two online detection modes separately, direct inductively coupled plasma mass spectrometry (ICP-MS) detection and high-performance liquid chromatography (HPLC)-ICP-MS detection. The CMCME-ICP-MS system is applicable for the analysis of MeHg+ and Hg2+ with the ratio of lower than 5/1, with the limits of detection (LODs) of 2.6 (MeHg+) and 5.8 (Hg2+) ng L-1 and throughput of 8 h-1. Comparatively, the CMCME-HPLC-ICP-MS system is universal for Hg speciation in cells, providing LODs of 9.7 and 18.9 ng L-1 for MeHg+ and Hg2+ with a throughput of 10 h-1. Both systems exhibited good endurance to complex cell matrix and automated operation. The species analysis of Hg in cells incubated by Hg2+ or MeHg+ was achieved and the demethylation of MeHg+ in HepG2 cells was observed.

In this study a second generation, perfectly branched dendrimer (D2) was synthesized using an iterative method via anhydride coupling from a bis-MPA monomer and a pentaerythritol core. The multigram scale production of this dendrimer in the lab enabled a multifaceted investigation of structure-bulk property relationships and a subsequent comparison with those of the second generation of a chemically similar but hyperbranched polymer (HBP2) produced via rapid one-pot synthesis from a bis-MPA monomer and an ethoxylated pentaerythritol core. Several characterization tools such as 1H NMR, FTIR, DSC, WAXS, and high-pressure dilatometry were employed to explicate fundamental differences and similarities between these two important dendritic polymer subclasses. Specifically, high pressure dilatometry permitted an investigation of temperature and pressure effects on specific volume (PVT) of the dendrimer and its HBP analogue. Fitting PVT data to the Simha-Somcynsky (S–S) equation of state (EOS) for the melt state enabled demonstration the power of this EOS, originally developed for linear polymers, to also fully describe the PVT surfaces of the dendrimer and HBP in this study. Generated molecular parameters from the S–S model were compared with those for other polymeric systems. Finally, fractional free volume for the dendrimer and HBP, determined from the PVT data and the S–S model, at various temperatures and pressures was compared.

This review focuses on magnetic nanomaterials as sorbents for trace elements analysis in environmental and biological samples. The design and preparation of magnetic nanomaterials with specific functional groups for trace elemental analysis are summarized, along with relevant adsorption mechanism. The application of these magnetic sorbents in different operation modes for the quantification of trace elements and their species in environmental and biological samples are discussed. The trend of development in this field is also prospected.

The use of porous carrier and coating sorbents in stir bar sorptive extraction (SBSE) contributes to the improvement of extraction efficiency and dynamics. Herein, porous nickel foam (NF) with large surface area and magnetic property was used as the carrier of stir bar. NF was added into the mixture of graphene oxide (GO) and reducing agent, and reduced graphene oxide (RGO) coating was obtained on the surface of NF substrate by in situ hydrothermal reduction. The characterization results of Fourier transform infrared spectroscopy, X-ray power-diffraction and scanning electron microscope showed that GO was partially reduced into RGO, and the RGO coating was uniformly loaded on the NF surface. The obtained RGO-NF composite was used as the stir bar coating for the analysis of six benzotriazole (BZTs) UV absorbents. The extraction efficiency was between 48 and 64% for six BZTs. RGO-NF stir bar exhibited faster adsorption/desorption kinetics than commercial polydimethylsiloxane coated stir bar (50 min vs 120/360 min) due to its porous structure and large specific surface area. On this basis, a method of RGO-NF coated stir bar sorptive extraction combined with high performance liquid chromatography (HPLC)-DAD was established for the determination of six BZTs. Under the optimized conditions, the limits of detection were 0.33–0.50 μg/L for six target BZTs, and the linear range was 1–100 μg/L. The proposed method merits good ability to resist matrix and was used to analyze six BZTs in environmental water samples. The recoveries of target BZTs were obtained within 83.0–112% in the spiked East Lake water and 97.0–111% in the spiked Yangtze River water, respectively.

In recent years, the fabrication of multifunctional superamphiphobic materials has received increasingly attention. In the present study, a kind of superamphiphobic coating with low-cost, good robustness, chemical stability and self-cleaning property was prepared through spraying epoxy resin (EP) and natural sepiolite (SEP) modified by fluorinated polysiloxane (FPOS). The proposed coating (SEP@FPOS/EP) exhibited excellent superamphiphobicity to water, ordinary liquid and oil, even sunflower oil with a surface energy as low as 27 mN m−1. Moreover, due to the addition of EP, the coating still maintained good superamphiphobicity even after being impacted by 100 g sand. This suggested that it had excellent mechanical stability. Besides, the SEP@FPOS/EP coating showed good repellent to aqueous solution with pH values from 1 to 13, salty solution as well as water droplets at different temperatures. Moreover, the SEP@FPOS/EP coating could keep excellent superamphiphobicity under UV light or after being placed in an environment of −10 °C. More importantly, the SEP@FPOS/EP coating had low adhesion to water, oil and dirty, indicating it owned superior self-cleaning property. All these outstanding performances and the facile fabrication method confirmed that SEP@FPOS/EP superamphiphobic coating could be used in various fields and large-scale production.

Avian influenza viruses are the pathogens of global poultry epidemics, and may even cause the human infections. Here, we proposed a novel inductively coupled plasma mass spectrometry (ICP-MS) based immunoassay with gold nanoparticles (Au NPs) labeling for the determination of H9N2 virions. Magnetic-beads modified with anti-influenza A H9N2 hemagglutinin mono-antibody (mAb-HA) were utilized for the capture of H9N2 virions in complex matrix; and Au NPs conjugated with mAb-HA were employed for the specific labeling of H9N2 virions for subsequent ICP-MS detection. With a sandwich immunoassay strategy, this method exhibited a high specificity for H9N2 among other influenza A virions such as H1N1 and H3N2. Under the optimized conditions, this method could detect as low as 0.63 ng mL − 1 H9N2 virions with the linear range of 2–400 ng mL − 1 , the relative standard deviation for seven replicate detections of H9N2 virions was 7.2% (c = 10 ng mL − 1 ). The developed method was applied for the detection of H9N2 virions in real-world chicken dung samples, and the recovery for the spiking samples was 91.4–116.9%. This method is simple, rapid, sensitive, selective, reliable and has a good application potential for virions detection in real-world samples.

Polydimethylsiloxane (PDMS)/MIL-100(Fe) coated stir bar was prepared by sol gel technique, and good preparation reproducibility was achieved with relative standard deviations (RSDs) ranging from 2.6% to 7.5% (n=7) and 3.6% to 10.8% (n=7) for bar-to-bar and batch-to-batch, respectively. Compared with commercial PDMS coated stir bar (Gerstel) and PEG coated stir bar (Gerstel), the prepared PDMS/MIL-100(Fe) stir bar showed better extraction efficiency for target triazines compounds. It also exhibited relatively fast extraction/desorption kinetics and long lifespan. Based on it, a method of PDMS/MIL-100(Fe) coated stir bar sorptive extraction (SBSE)-high performance liquid chromatography-ultraviolet detector (HPLC-UV) was developed for the determination of six triazines (simazine, atrazine, prometon, ametryn, prometryne and prebane) in environmental water samples. Several parameters affecting SBSE of six target triazines including extraction time, stirring rate, sample pH, ionic strength, desorption solvent and desorption time were investigated. Under the optimal experimental conditions, the limits of detection (LODs, S/N=3) were found to be in the range of 0.021-0.079μgL-1. The repeatability RSDs were in the range of 2.3-6.3% (n=7, c=0.5μgL-1) and the enrichment factors (EFs) ranged from 51.1 to 102-fold (theoretical EF was 200-fold). The proposed method was applied to the analysis of target triazines in environmental water samples, with recoveries of 98.0-118% and 94.0-107% for spiked East Lake water and local pond water samples, respectively.