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Background: Peripheral immunity and neuroinflammation interact with each other and they play important roles in the pathophysiology of idiopathic Parkinson's disease (IPD). There have been very few real-world reports on the relationship between peripheral immune inflammation and motor phenotypes of IPD. This study aimed to investigate the potential correlation between peripheral inflammatory indicators and motor subtypes in patients with IPD. Methods: This observational, prospective case-control study examined patients with IPD and healthy controls (HC) matched for age and sex between September 2021 and July 2023 at the Affiliated Huaian No. 1 People's Hospital of Nanjing Medical University. The levels of peripheral inflammatory indicators were collected from each patient with IPD and HCs. Differences in the levels of peripheral inflammatory indicators among groups were compared. Binary logistic regression analysis was used to explore the inflammatory mechanism underlying the motor subtype of IPD. Results: A total number of 94 patients with IPD were recruited at the Affiliated Huaian No. 1 People's Hospital of Nanjing Medical University between September 2021 and July 2023, including 49 males and 45 females, and 37 healthy volunteers matched for age and sex were also enrolled as the control group. Of the 94 patients with IPD, 42.6% performed as the TD motor subtype and 57.4% performed as the AR motor subtype. NLR and the plasma levels of IL-1βand TNF-α in the IPD group were higher than those in the HC group (P < 0.05). The disease duration, Hoehn and Yahr (H-Y) stage, NLR, and the levels of IL-1β in the AR group were higher than those in the TD group (P < 0.05). Additionally, IL-1β plasma levels and NLR were positively correlated with disease duration, H-Y stage, movement disorder society-Unified Parkinson's Disease Rating Scale-III motor score, and AR subtype. The binary logistic regression model revealed that the plasma level of IL-1β was mildly associated with the AR motor subtype and NLR was strongly associated with the AR motor subtype. The combination of NLR and IL-1β showed better performance in identifying the AR motor subtype. Conclusion: NLR is strongly associated with the AR motor subtype in IPD, and peripheral immunity is probably involved in the pathogenesis of AR motor subtype in IPD. [ABSTRACT FROM AUTHOR]

Constructing frustrated Lewis pairs (FLPs) on catalysts will provide catalytic sites to activate CO2 and boost photocatalytic CO2 reduction. Herein, a Ce-doped bismuth oxide (CeBiOX) with FLPs was designed by loading [(α-SbW9O33)2Cu3(H2O)3]12− (Cu3) via strong electrostatic interactions to create oxygen vacancies (OVs). Detailed experiments and measurements showed that Cu3 could regulate the FLPs and optimize the band structure of CeBiOX to boost photocatalytic CO2 reduction. In particular, the Cu3/CeBiOX composite exhibited the highest yields of CO (42.85 μmoL g−1) and CH4 (13.23 μmoL g−1), being 6.6 and 3.3 times, and 4.9 and 6.3 times higher than those of pristine Bi2O3 and CeBiOX, respectively. This work provides a significant and mild approach to obtaining advanced catalysts with tuneable FLPs for more fields. [ABSTRACT FROM AUTHOR]

With the increasing proportion of the aging population, neurodegenerative diseases have become one of the major health issues in society. Neurodegenerative diseases (NDs), including multiple sclerosis (MS), Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS), are characterized by progressive neurodegeneration associated with aging, leading to a gradual decline in cognitive, emotional, and motor functions in patients. The process of aging is a normal physiological process in human life and is accompanied by the aging of the immune system, which is known as immunosenescence. T-cells are an important part of the immune system, and their senescence is the main feature of immunosenescence. The appearance of senescent T-cells has been shown to potentially lead to chronic inflammation and tissue damage, with some studies indicating a direct link between T-cell senescence, inflammation, and neuronal damage. The role of these subsets with different functions in NDs is still under debate. A growing body of evidence suggests that in people with a ND, there is a prevalence of CD4+ T-cell subsets exhibiting characteristics that are linked to senescence. This underscores the significance of CD4+ T-cells in NDs. In this review, we summarize the classification and function of CD4+ T-cell subpopulations, the characteristics of CD4+ T-cell senescence, the potential roles of these cells in animal models and human studies of NDs, and therapeutic strategies targeting CD4+ T-cell senescence. [ABSTRACT FROM AUTHOR]

Defective metal–organic frameworks-based composites with excellent separation properties were obtained. The mesoporous metal–organic frameworks were selected and deliberately designed to be deficient, and they were then combined with polyacrylamide to be modified on the surface of silica microspheres. The prepared composites were employed as mixed-mode stationary phase in chromatographic separation, and they were compared to both conventional microporous metal–organic framework-based columns and commercial columns. It showed improved selectivity and retention toward both hydrophilic and hydrophobic analytes, allowing for the effective separation of nine nucleosides and nucleobases, eight alkaloids, six antibiotics, and five alkylbenzenes. Additionally, the column was used to effectively separate the active ingredients in the daring substance of honeysuckle, revealing a wide range of possible applications. For the same batch of analytes, three batches of distinct materials demonstrated consistent separation effects. It also demonstrated excellent chromatographic repeatability and stability, with relative standard deviations of the retention time and/or column efficiency being found to be less than 0.8% and 0.9%, respectively. The dispersive hierarchically porous composites were demonstrated to be effective in chromatographic separation, and the results expanded the potential uses of defective MOFs with dispersed multi-level pores. [ABSTRACT FROM AUTHOR]

The preparation of different carbon-shell morphology microspheres and controllable surface area via using thermoplastic polymers as carbon source was still a challenge. In addition, the unique structure of porous Silica@Carbon (Sil@C) microspheres not only can provide larger surface area and active site, but also have the characteristics of high mechanical strength and easy modification. Herein, we report a simple method to in-situ fixation a series of different morphology graphitized carbon shell (rosa roxburghii, bulk, and carbon sphere shapes) on porous silica microspheres surface. Metal salt assisted polymer carbonization will not only prepare graphitized carbon with different morphology on silica surface, but also facilitate the in-situ carbonization of thermoplastic polymer on the silica microspheres surface instead of internal pores; the more heat of metal salt released during carbonization, the larger the specific surface area of Sil@C. [ABSTRACT FROM AUTHOR]

A novel ZIF-8 assisted polyacrylamide functionalized silica polar stationary phase was prepared by a facile method of adding ZIF-8 nanoparticles and silica into polyacrylamide (PAM) aqueous solution, and then stirring the mixture until the solution was evaporated absolutely with the help of mechanical agitator. Interestingly, the prepared stationary phase (PAM-Sil@ZIF-8/PAM) showed favorable hydrophilicity, as demonstrated by good separation performance and strong retention ability toward several types of polar compounds, such as amino acids, saccharides, and alkaloids. In addition, PAM-Sil@ZIF-8(50 mg)/PAM showed better separation performance compared with amino-modified silica and Sil/PAM stationary phase due to the addition of ZIF-8. Furthermore, it was demonstrated that the addition of ZIF-8 improved the specific surface area and provided extra interaction sites for the stationary phase and analytes, which is beneficial for the separation of samples. In addition, the column efficiency can reach 7861.9 plates/m for colchicine. Moreover, it exhibited good stability and reproducibility under our operation conditions. In short, a novel stationary phase, which can be used for hydrophilic interaction liquid chromatography, was obtained and proved that the separation performance of polymer modifying silica stationary phase can be greatly improved by the addition of MOF nanoparticles. [ABSTRACT FROM AUTHOR]

Cinnamomum camphora is an evergreen tree that contains essential oils and the leaf is the main organ used to extract essential oils. Isoprenoid is a key component contributing to the essential oils of C. camphora. Still, the molecular mechanisms and regulatory pathways underlying isoprenoid biosynthesis remain to be explored. In our study, we found that the content of linalool was higher in 65-day-old leaves than that in 15-day-old leaves of linalool-type C. camphora. The leaf proteome of these two materials was then analyzed based on data-independent acquisition, respectively, and 11,503 proteins were identified, of which 11,076 were annotated. Analysis of differentially expressed proteins revealed that the expression levels of MCT, MDS, and AACT increased significantly in 65-day-old leaves. Further analysis of the protein interaction network indicated that 15 differentially expressed proteins related to isoprenoid biosynthesis were co-expressed, and also suggested that the transcription factor families of BES1, C3H, MYB, NF-YC, Nin-like, WRKY, ZF-HD, and bHLH may act as candidate regulators of leaf development in C. camphora. Our study verified that the process of isoprenoid biosynthesis in C. camphora is regulated by a complicated network consisting of conserved synthetases, and provides proteomic information for further investigation of isoprenoid metabolic. [ABSTRACT FROM AUTHOR]

Sub-2-µm sea-urchin-like TiO2 microspheres were prepared through the one-step solvothermal method. Results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that there are a lot of nanorods coming out from the center of the TiO2 microsphere, making it look like a sea urchin. The morphology and structure of these microspheres are very suitable for chromatographic packing. During the separation of inorganic anions on this new stationary phase, the retention mechanism is electrostatic interaction, and the pH of the mobile phase plays an important role in retention behaviors. With this new stationary phase for separation of organic anions and nucleobases, Lewis acid–base interaction is more outstanding, which can cause peak broadening and tail for larger conjugated structure compounds. The separation of aromatic hydrocarbons on this new stationary phase demonstrates that Lewis acid–base interaction has a favorable influence on the separation of electron-rich aromatic hydrocarbons under normal phase chromatographic conditions. [ABSTRACT FROM AUTHOR]

Store-operated Ca2+ entry (SOCE) is a major pathway for calcium signaling, which regulates almost every biological process, involving cell proliferation, differentiation, movement and death. Stromal interaction molecule (STIM) and ORAI calcium release-activated calcium modulator (ORAI) are the two major proteins involved in SOCE. With the deepening of studies, more and more proteins are found to be able to regulate SOCE, among which the transmembrane (TMEM) family proteins are worth paying more attention. In addition, the ORAI proteins belong to the TMEM family themselves. As the name suggests, TMEM family is a type of proteins that spans biological membranes including plasma membrane and membrane of organelles. TMEM proteins are in a large family with more than 300 proteins that have been already identified, while the functional knowledge about the proteins is preliminary. In this review, we mainly summarized the TMEM proteins that are involved in SOCE, to better describe a picture of the interaction between STIM and ORAI proteins during SOCE and its downstream signaling pathways, as well as to provide an idea for the study of the TMEM family proteins. [ABSTRACT FROM AUTHOR]

By introducing functional groups such as quaternary amine groups, sulfonic acid groups, triazine groups, and other mespore nanomaterials into the hydrogel, better separation effect of some organic framework materials has been obtained. Due to a reasonable design and preparation strategy, the hydrogel composite-modified silica can be used in the selective separation of various analytes such as pesticides, alkylbenzenes, polycyclic aromatic hydrocarbons, nucleosides/bases, benzoic acids, antibiotics, and carbohydrates. Through the exploration of chromatographic retention behavior, it is proved that the column can be used in mixed-mode liquid chromatography. The intra-day relative standard deviation for retention time of this new stationary phase is 0.12–0.16% (n = 10), and the inter-day relative standard deviation is less than 0.39% (n = 5). This new stationary phase can also be used for separation in complex samples. The limit of detection (LOD) for chlorotoluron in farm irrigation water is 0.21 µg/L and the linear range is 2–250 µg/L. After optimizing the chromatographic conditions, the highest efficiency of the hydrogel column in RPLC and HILIC modes has reached 32,400 plates/m (chlorobenzuron) and 41,300 plates/m (galactose). This new type of hydrogel composite is a porous network material with flexible functional design and simple preparation method and its application has been expanded in liquid chromatography separation successfully. The hydrogel composed of triallyl cyanate cross-linking agent and 3-(2-(methacryloyloxy) ethyl) dimethylamine) propane-1-sulfonate (SBMA) monomer which were co-modified on the surface of mesoporous silica with MOF-919 for separation in mixed-mode liquid chromatography. [ABSTRACT FROM AUTHOR]

Inspired by porous smart gel materials, we designed pH-responsive polymer-modified silica microspheres as liquid chromatography stationary phase materials by a one-step strategy. The free radicals generated by the oxidation of dopamine are used to initiate the cross-linking polymerization of functional monomers. At the same time, the good adhesion of dopamine enables the polymer to be modified on silica. The hydrophilicity of this new stationary phase can change in response to the pH of the mobile phase and the stationary phase has weaker hydrophilicity under acidic (pH = 3.78) mobile phase conditions and stronger hydrophilicity under neutral mobile phase conditions. The hydrophilicity difference of the stationary phase leads to the selectivity difference in separation. To evaluate the chromatographic performance of this new stationary phase, 10 oligosaccharides and 9 nucleosides/bases were separated on this stationary phase. This paper will provide good guidance for us to achieve more pH-responsive hydrophilic/hydrophobic stationary phases in the future. [ABSTRACT FROM AUTHOR]

The synthesis of two-dimensional metal–organic frameworks (2D MOFs)/polymer core–shell composites is reported which were composed of polydopamine modified 2D Zr-1,3,5-(4-carboxylphenyl)-benzene (2D Zr-BTB) nanosheets and silica microspheres via a double-solvent approach. In this way, the composites were obtained under the condition of two solvents with different polarities to avoid agglomeration and uneven modification of most MOFs particles on the surface of the silica, existing inevitably in the one-pot method. Compared with the reported MOFs@silica composites adopting one-pot solvent method, the prepared composites exhibited significantly enhanced separation performance for sulfonamides, antibiotics, nucleosides, and polycyclic aromatic hydrocarbons compounds. Furthermore, the retention mechanisms were demonstrated by studying the relationships of chromatographic retention factors of tested analytes versus a variety of parameters under RPLC and HILIC modes, respectively. The superior chromatographic repeatability and stability were validated through the relative standard deviations of the retention time and/or column efficiency, which were found to be less than 0.8% and 0.9%, respectively. The material showed efficient separation ability for several types of compounds and provided another selectivity for preparing composites based on 2D MOFs nanosheets and other functional molecules. [ABSTRACT FROM AUTHOR]

Traditional textiles with hydrophilic properties can absorb sweat secreted from the skin, but cause an undesirable cold sensation and adhere to the skin. Textiles with an effect similar to an air conditioner and sensing properties have attracted great interest because of their desirable performance, comfort, and energy-saving properties. However, fabricating functional textiles with moisture management and pH identification properties remains a difficult challenge. Herein, we demonstrate a fluorine-free hydrophobic loofah fabric with embedded thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) microspheres as microplugs, which endowed it with directional liquid transport and body temperature regulation depending on the temperature. Based on the phase separation of the microplugs and capillary gradients, the microplugs of the self-venting textile are opened and generate drying and cooling effects via high moisture transport in hot weather, whereas the pores of the microplugs close to retain heat in cold weather. Moreover, the multifunctional loofah textile exhibits hydrophobic or hydrophilic behaviour for droplets with different pH values, which can provide real-time liquid signal detection. The water repellency and the wicking, permeability, and mechanical properties of the hydrophobic outer surface of the loofah textile are not affected by harsh conditions. This study not only provides ideas for the design and preparation of textiles for personal comfort, but also environmentally friendly and acid/alkali-protective clothing with great potential applications in demanding situations. [ABSTRACT FROM AUTHOR]

Store-operated Ca2+ entry (SOCE) is the major pathway of Ca2+ entry in mammalian cells, and regulates a variety of cellular functions including proliferation, motility, apoptosis, and death. Accumulating evidence has indicated that augmented SOCE is related to the generation and development of cancer, including tumor formation, proliferation, angiogenesis, metastasis, and antitumor immunity. Therefore, the development of compounds targeting SOCE has been proposed as a potential and effective strategy for use in cancer therapy. In this review, we summarize the current research on SOCE inhibitors and blockers, discuss their effects and possible mechanisms of action in cancer therapy, and induce a new perspective on the treatment of cancer. [ABSTRACT FROM AUTHOR]

A general method was developed for preparing a metal–organic framework–polymer composite coated silica core–shell stationary phase. Silica microspheres were comodified with metal–organic framework and polyvinylpyrrolidone rather than the in situ method of silica modification by original metal–organic framework particles. Metal–organic framework particles and polyvinylpyrrolidone on silica surface were beneficial to suppress silanol activity and enhance composite material tolerance, as well as increasing the water compatibility of the original metal–organic framework-based stationary phases. The stationary phase exhibited superior hydrophilic and hydrophobic performance in terms of separation for various analytes including seven alkaloids, six sulfonamides, five antibiotics, and five polycyclic aromatic hydrocarbons. Moreover, the composite material also showed excellent stability with the relative standard deviation of the retention time of 0.4 to 0.7%. The separation performance with real samples proved that the column has good practical application potential. In summary, the poposed method provides a general way for preparing metal–organic framework–polymer composite material and changed the current status of original metal–organic framework particles modified silica as a single mode chromatographic stationary phase. [ABSTRACT FROM AUTHOR]

Using N-isopropylacrylamide (NIPAM) as a monomer, a core–shell material was successfully prepared via in situ polymerization on the surface of silica microspheres (named NIPAM@Sil), which acts as a hydrophilic interaction chromatography (HILIC) stationary phase. A method for the in situ polymerization of polymer monomers on a silica surface has been developed. It was shown using scanning electron microscopy (SEM) that NIPAM is evenly distributed on the surface of the silica. The synthesized NIPAM@Sil possesses a polar acylamino group arising from the polymerization of NIPAM. As demonstrated by the hydrophilicity, NIPAM@Sil showed excellent HILIC performance for the separation of hydrophilic compounds. This method provides a simple approach for the preparation of a polymer coated silica core–shell stationary phase. [ABSTRACT FROM AUTHOR]

A new type of core–shell composite material was prepared and applied as a hydrophilic interaction liquid chromatography (HILIC) stationary phase. In this work, silica spheres were first modified with a bimetallic central metal–organic framework (ZnCoMOF) by a new strategy of static self-assembled in situ growth. This strategy was beneficial for increasing the electrostatic interaction between the MOF ligand and silica via introducing a sodium dodecylbenzenesulfonate (SDBS) group. The ZnCoMOF@silica stationary phase was characterized and evaluated in comparison with amino-modified and bare silica columns in terms of various polar analytes including eight nucleosides and nucleobases, seven carbohydrates, and multiple sulfonamides and antibiotics. The effects of organic solvent concentration, water content, the concentration of the salt and the pH of the buffer solution on the retention time were studied, which demonstrated the typical retention behavior of HILIC on the ZnCoMOF@silica column. Compared with most reported MOF-based stationary phases, the new composite material showed excellent hydrophilic properties and separation efficiency for various polar analytes. Moreover, the obtained stationary phase showed good reproducibility and stability. The relative standard deviation (RSD) of the retention time for repeatability was found to range from 0.1% to 0.6%, and the RSD of the retention time for stability was found to range from 0.3% to 0.7%. Furthermore, the column batch-to-batch reproducibility showed excellent preparation reproducibility, which few reported in most previous MOF@silica composite materials. This specific preparation method offers an easy and novel way to manipulate the amount of MOF particles on silica, which extends a universal way to produce various MOF@silica stationary phases by the method of static self-assembled in situ growth. [ABSTRACT FROM AUTHOR]

A magnetic solid-phase extraction (MSPE) technique coupled with high performance liquid chromatography (HPLC) was developed and used for bioaccumulation investigation of bisphenol A (BPA) in HepG2 cells and zebrafishes. Cobalt magnetic polystyrene microsphere derived carbon (C–Co@PST) as an adsorbent was prepared by in situ polymerization reaction and further annealing treatment. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy and X-ray diffraction were employed to confirm successful synthesis of C–Co@PST. A series of extraction parameters including the amount of the sorbent, the type of elute, extraction time and elution time were investigated to achieve high extraction efficiency. C–Co@PST based MSPE combined with HPLC was successfully established for bioaccumulation research of BPA in living creatures. It was found that the bioconcentration values of BPA in HepG2 cells underwent an increase, then a decrease, and finally reached an equilibrium level of 11.60 μg kg−1 at 8 h. The concentration of BPA in zebrafishes increased ranging from 6.05 μg kg−1 to 31.84 μg kg−1 over a culture time from 1 h to 12 h. Furthermore, linear and exponential models were employed to analyse the bioconcentration variation of BPA in organisms over the exposure time. Mathematical models have been developed to predict the transfer characteristics of BPA. [ABSTRACT FROM AUTHOR]

A strategy based on in situ growth of a metal–organic framework composite material was proposed by introducing a sodium dodecyl benzenesulfonate (SDBS) group to increase the electrostatic interaction between the MOF ligand and silica. In this work, mesoporous silica spheres were first functionalized with a zirconium-(IV)-based metal–organic framework material (MOF-808), which produced a core–shell particle (MOF-808@silica) as a hydrophilic interaction liquid chromatography (HILIC) stationary phase. The obtained material improves and enhances the selectivity and stability of the stationary phase in traditional MOF-based HILIC. A series of methods such as elemental analysis, scanning electron microscopy, Fourier-transform infrared spectroscopy, and Brunauer–Emmett–Teller were used to confirm that MOF-808 was successfully modified onto silica. The relative standard deviation (RSD) of the retention time for stability with 120 h of continuous elution was found to range from 0.2% to 0.6%, and the RSD of the repeatability for 10 replicates of continuous elution was found to range from 0.1% to 0.3%. Furthermore, the column batch-to-batch reproducibility of the retention time was reproducible with an RSD of less than 2.2% depending on the analyte. The composite materials were found to be superior to most reported MOF-based stationary phases in terms of separation performance for various polar compounds, preparative reproducibility, and chromatographic stability. In short, MOF-808@silica composite material expands and improves the use of MOF materials as stationary phases in hydrophilic chromatography, revealing a method to prepare a MOF@silica composite that shows good performance when used for chromatographic analysis. [ABSTRACT FROM AUTHOR]

Magnetic hierarchical nickel/nickel oxide/carbon nanorods (Ni/NiO@C) were prepared via the pyrolysis of a metal-organic framework containing nickel(II) nickel (Ni-MOF; Ni3(BTC)2) under argon atmosphere. In this material, magnetic Ni/NiO@C nanoparticles are embedded in porous carbon nanorods, and the morphology is similar to that of the original Ni-MOF precursor. The synthesized nanorods were applied as magnetic sorbents in the solid-phase extraction of five benzoylurea insecticides (flufenoxuron, chlorbenzuron, teflubenzuron, diflubenzuron and triflumuron), and their performance was evaluated under optimized conditions. The results show that the material exhibits high extraction recoveries from spiked samples (82.9%–107.6%) and linear response in the range of 0.2–450 μg·L−1. It is also characterized by relatively low limits of detection (50–100 ng·mL−1) at a signal-to-noise ratio of 3. The sorbent is chemically stable and can be repeatedly recycled, with little decline in extraction capacity after 20 cycles of reuse. The method was successfully applied to the quantification of benzoylureas in tea, wolfberry, millet, and oat samples, and it showed high extraction efficiency. [ABSTRACT FROM AUTHOR]

A metal organic framework (MOF-235) was fabricated by a simple solvothermal method and utilized as an adsorbent for the selective removal of electron-rich conjugated dyes. Parameters that influenced the adsorption process were investigated and the excellent adsorption properties of MOF-235 toward Congo red (CR) and lemon yellow (LY) are also exhibited in a wide range of pH 3–9. Moreover, the adsorption kinetics and thermodynamics were determined, indicating that the Langmuir model can well describe the adsorption isotherm and the pseudo-second order model can satisfactorily describe the adsorption kinetics. Thanks to the large hydrophobic effect between electron-deficient MOF and electron-rich conjugated dye molecules, the ultrahigh maximum adsorption capacity for CR and LY calculated by the Langmuir model is up to 1250 and 250 mg g−1, respectively, which surpass that of most reported adsorbents. Notably, the maximum adsorption capacity of adsorption of CR and LY is up to 1131 and 209 mg g−1 in fruit juice, respectively. Additionally, the synthesized MOF-235 has a high adsorptive selectivity and fast adsorption rate and can be regenerated for removal by washing with ethanol containing NaOH solution. These results demonstrated that MOF-235 would be an effective and easily reusable adsorbent for the adsorptive removal of CR and LY from fruit juice. [ABSTRACT FROM AUTHOR]

Herein, a novel, fusiform-like magnetic metal–organic framework material (Fe3O4-NH2@MOF-235) was fabricated by a facile two-step solvothermal approach. Then, Fe3O4-NH2@MOF-235 was applied as an adsorbent in magnetic solid-phase extraction (MSPE) coupled with high-performance liquid chromatography (HPLC) for the simultaneous extraction and determination of five kinds of benzoylurea insecticides (flufenoxuron, chlorbenzuron, teflubenzuron, diflubenzuron and triflumuron) from honey, fruit juice and tap water samples. Moreover, potential variables influencing the MSPE efficiency were optimized. Under the optimized conditions, an excellent linearity was achieved in the range of 1.0–300.0 μg L−1 for teflubenzuron and flufenoxuron and 2.0–300.0 μg L−1 for diflubenzuron, chlorbenzuron and triflumuron, with the correlation coefficients of 0.9991–0.9995. The limits of detection for the analytes were 0.25–0.5 μg L−1, and the recoveries at three fortified concentration levels ranged from 76.45% to 90.74% for the honey samples, 79.95–95.27% for the fruit juice samples, and 84.02–99.62% for the tap water samples. The π–π stacking and hydrophobic interactions between Fe3O4-NH2@MOF-235 and the analytes played an important role in the adsorption process. Moreover, maximum adsorption could be achieved within 5 minutes with very little adsorbent for all the samples. Therefore, the magnetic Fe3O4-NH2@MOF-235 composite combined with MSPE is a convenient approach to detect benzoylurea insecticides in actual samples. [ABSTRACT FROM AUTHOR]

A zirconium(IV)‐based metal–organic framework material (MOF‐808) has been synthesized in a simple way and used for the extraction of phenoxyacetic acids in complex samples. The material has good thermal and chemical stability, large specific surface area (905.36 m²/g), and high pore size (22.18 Å). Besides, it contains a large amount of Zr‐O groups, easy‐to‐form Zr‐O‐H bond with carboxyl groups of phenoxyacetic acids, and possesses biphenyl skeleton structure, easy to interact with compounds through π‐π and hydrophobic interactions. These characteristics make the material very suitable for the extraction of certain compounds with a high extraction efficiency and excellent selectivity. The extraction conditions were optimized, and then an analytical method was successfully established and applied for analysis of actual samples. The solid‐phase extraction method based on prepared material had a wide linear range of 0.2–250 μg/L and a low detection limit of 0.1–0.5 μg/L for four phenoxyacetic acid compounds including 2,4‐dichlorophenoxyacetic acid, 2‐(2,4‐dichlorophenoxy) propionic acid, 4‐chlorophenoxyacetic acid, and dicamba. The relative standard deviations of intra‐ and interday precision were 1.8–3.8 and 4.3–6.9%, and the recoveries after spiking were between 77.1 and 109.3%. The results showed that the material is a desired substituent for the extraction of compounds with benzene ring structure containing carboxyl groups. [ABSTRACT FROM AUTHOR]

Au nanoparticle-hybridized silica (Au@sil) spheres were synthesized in one step as a liquid chromatographic stationary phase for the first time. The hybridized stationary phase showed good separation performances in reversed-phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography even without bonding with any organic groups. Compared with the bare silica stationary phase, the Au@sil stationary phase showed better separation performance under the same conditions in RPLC and HILIC modes. The effects of acetonitrile content, buffer concentration, and the pH of the mobile phase on analyte retention were further investigated. The results showed that the Au@sil stationary phase had a complex retention mechanism of electrostatic and partitioning interactions. By comparing Au solution (solAu) with different proportion volumes in silica sol, the optimum hybridized stationary phase was found to comprise 33 vol% solAu. Au@sil was further modified with 1-octadecanethiol by self-assembly and used to separate alkylbenzenes and polycyclic aromatic hydrocarbons by RPLC. The separation efficiency of the 1-octadecanethiol self-assembled modified Au@sil (C18-Au@sil) column was much better than that of Au@sil. Overall, the successful hybridization of Au nanoparticles provided a new method to prepare a stationary phase in a simple and environmentally friendly way. [ABSTRACT FROM AUTHOR]

A zirconium(IV)‐based metal organic framework, composed of 4,4′‐biphenyldicarboxylic acid ligands and Zr6O4(OH)4 clusters, was successfully fabricated. Characterizations were performed on fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, Brunauer‐Emmett‐Teller, and thermogravimetric analysis, which confirmed that it possessed large specific surface area, high pore volume, and strong acid resistant stability. Furthermore, the prepared material containing biphenyl skeleton and a large number of Zr‐O bonds, can grasp acid herbicides especially phenoxyacetic acid herbicides with aromatic structures through π‐π interaction, hydrophobic interaction and Zr‐O‐H+ bonds. Based on these advantages, a method was developed for the determination of four phenoxyacetic acid herbicides from vegetable samples. Under the optimal conditions, wide linearities from 0.3 to 250 μg/L and low limits of detection from 0.1 to 0.5 μg/L were obtained. The intra‐ and interday relative standard deviations were 1.56‐3.92 and 5.01‐7.65%, respectively. The proposed method was applied to analyze phenoxyacetic acid herbicides residues in the tomato, cucumber, and white gourd samples. The satisfactory recoveries (86.12–103.44%) for the spiked samples in vegetable samples were achieved which demonstrated the method was an efficient pretreatment procedure and has a potential application for the trace determination of phenoxyacetic acids from a complex matrix. [ABSTRACT FROM AUTHOR]

Packed cartridges have been widely used in solid-phase extraction. However, there are still some drawbacks, such as they are blocked easily and the method is time-consuming. In view of the advantages of monoliths, a monolithic extraction material has been directly synthesized in a glass syringe without any gap between the monolith and syringe inner wall. The monolithic syringe was modified with graphene oxide by loading graphene oxide dispersion onto it. The content of graphene oxide and the surface topography of the monolith have been evaluated by elemental analysis and scanning electron microscopy, respectively, which confirmed the successful modification. This prepared graphene oxide-modified monolithic syringe was directly used as a traditional solid-phase extraction cartridge. As expected, it shows good permeability and excellent capability for the extraction of quaternary ammonium alkaloids. The sample loading velocity (1-6 mL/min) does not affect the recovery. Under the optimal conditions, good linearities ( R = 0.9992-0.9998) were obtained for five quaternary ammonium alkaloids, and the limits of detection and quantification were 0.5-1 and 1-2 μg/L, respectively. The proposed method was successfully applied for the analysis of quaternary ammonium alkaloids in Chinese patent medicine. [ABSTRACT FROM AUTHOR]

In the KOH medium, the as-prepared gold nanorods (AuNR) were aggregated to AuNR aggregates that exhibited strong resonance Rayleigh scattering (RRS) at 440 nm. Formaldehyde reacted with 4-amino-3-hydrazino-5-mercap-1,2,4-triazole (AHMT) to form a purplish red compound 6-mercapto-S-triazole [4,3-b]-S-tetrazole with strong hydrophobic ability that as receptors were closed to the surfaces of AuNR aggregates as donors. When the system was irradiated, the RRS-energy transfer (RRS-ET) takes place, which results in the RRS signal quenching at 440 nm. With the increase of formaldehyde concentration, the formed receptors increased, and the RRS intensity quenched linearly at 440 nm due to the RRS-energy transfer enhancing. The quenched intensity responds linearly with formaldehyde concentration in the range of 0.25-48 μmol/L. Thus, a new AuNR surface plasmon RRS-ET method was developed for the determination of trace formaldehyde, with satisfactory results. [ABSTRACT FROM AUTHOR]

A new polyethylene glycol/graphene oxide composite material bonded on the surface of a stainless-steel wire was used for solid-phase microextraction. The layer-by-layer structure increased the adsorption sites of the novel fiber, which could facilitate the extraction of trace compounds. The polyethylene glycol/graphene oxide was characterized by Fourier transform infrared spectroscopy and elemental analysis, which verified that polyethylene glycol was successfully grafted onto the surface of graphene oxide. The performance of the polyethylene glycol/graphene oxide coated fiber was investigated for phenols and phthalate esters coupled with gas chromatography with flame ionization detection under the optimal extraction and desorption conditions, and the proposed method exhibited an excellent extraction capacity and high thermal stability. Wide linear ranges were obtained for the analytes with good correlation coefficients in the range of 0.9966-0.9994, and the detection limits of model compounds ranged from 0.003 to 0.025 μg/L. Furthermore, the as-prepared fiber was used to determine the model compounds in the water and soil samples and satisfactory results were obtained. [ABSTRACT FROM AUTHOR]

A novel organic-silica hybrid monolith was prepared through the binding of histidine onto the surface of monolithic matrix for mixed-mode per aqueous and ion-exchange capillary electrochromatography. The imidazolium and amino groups on the surface of the monolithic stationary phase were used to generate an anodic electro-osmotic flow as well as to provide electrostatic interaction sites for the charged compounds at low pH. Typical per aqueous chromatographic behavior was observed in water-rich mobile phases. Various polar and hydrophilic analytes were selected to evaluate the characteristics and chromatographic performance of the obtained monolith. Under per aqueous conditions, the mixed-mode mechanism of hydrophobic and ion-exchange interactions was observed and the resultant monolithic column proved to be very versatile for the efficient separations of these polar and hydrophilic compounds (including amides, nucleosides and nucleotide bases, benzoic acid derivatives, and amino acids) in highly aqueous mobile phases. The successful applications suggested that the histidine-modified organic-silica hybrid monolithic column could offer a wide range of retention behaviors and flexible selectivities toward polar and hydrophilic compounds. [ABSTRACT FROM AUTHOR]

CdS nanoparticles coated on a stainless-steel wire for solid-phase microextraction was prepared. Scanning electron microscopy showed that the CdS nanoparticles clustered together to form a porous structure and X-ray diffraction confirmed that the CdS nanoparticles were the wurtzite phase. Coupled to gas chromatography with flame ionization detection, the extraction abilities of the fiber for polycyclic aromatic hydrocarbons were examined by the headspace method. The parameters of adsorption time, adsorption temperature, salt concentration, desorption time, and desorption temperature were investigated and optimized. For the method, wide linearity and low limits of detection from 5 to 15 ng/L were obtained. The relative standard deviations for single-fiber repeatability and fiber-to-fiber reproducibility were less than 10.2 and 12.6%, respectively. The enrichment factors were from 1155.6 to 3905.4, showing the fiber has good extraction capacity for polycyclic aromatic hydrocarbons. Moreover, the fiber can be used more than 50 times, exhibiting good stability. The established method was also used to analyze the polycyclic aromatic hydrocarbons in two real samples, and the recoveries from 82.7 to 114.2% further proved the reliability of the method. [ABSTRACT FROM AUTHOR]

In the initial phase of this study, graphene oxide (GO)/silica was fabricated by assembling GO onto the silica particles, and then gold nanoparticles (GNPs) were used to modify the GO/silica to prepare a novel stationary phase for high-performance liquid chromatography. The new stationary phase could be used in both reversed-phase chromatography and hydrophilic interaction liquid chromatography modes. Good separations of alkylbenzenes, isomerides, amino acids, nucleosides, and nucleobases were achieved in both modes. Compared with the GO/silica phase and GNPs/silica phase, it is found that except for hydrophilicity, large π-electron systems, hydrophobicity, and coordination functions, this new stationary phase also exhibited special separation performance due to the combination of 2D GO with zero-dimensional GNPs. [ABSTRACT FROM AUTHOR]

In this paper, a kind of aminopropyl imidazole-modified silica sorbent was synthesized and used as a solid-phase extraction (SPE) sorbent for the determination of carboxylic acid compounds and polycyclic aromatic hydrocarbons (PAHs). The resultant aminopropyl imidazole-modified silica sorbent was characterized by Fourier transform infrared spectroscopy (FT-IR) and elemental analysis (EA) to ensure the successful binding of aminopropyl imidazole on the surface of silica gel. Then the aminopropyl imidazole-modified silica sorbent served as a SPE sorbent for the enrichment of carboxylic acid compounds and PAHs. The new sorbent exhibited high extraction efficiency towards the tested compounds and the results show that such a sorbent can offer multiple intermolecular interactions: electrostatic, π–π, and hydrophobic interactions. Several parameters affecting the extraction recovery, such as the pH of sample solution, the pH of eluent, the solubility of eluent, the volume of eluent, and sample loading, were also investigated. Under the optimized conditions, the proposed method was applied to the analysis of four carboxylic acid compounds and four PAHs in environmental water samples. Good linearities were obtained for all the tested compounds with R2 larger than 0.9903. The limits of detection were found to be in the range of 0.0065–0.5 μg L−1. The recovery values of spiked river water samples were from 63.2% to 112.3% with relative standard deviations (RSDs) less than 10.1% (n = 4). [ABSTRACT FROM AUTHOR]

An octadecylsilane functionalized graphene oxide/silica stationary phase was fabricated by assembling graphene oxide onto the silica particles through an amide bond and subsequent immobilization of octadecylsilane. The chromatographic properties of the stationary phase were investigated by reversed-phase chromatography with alkylbenzenes, polycyclic aromatic hydrocarbons, amines, and phenolic compounds as the analytes. All the compounds achieved good separation on the column. The comparison between a C18 commercial column and the new stationary phase indicated that the existence of π-electron system of graphene oxide allows π-π interaction between analyte and octadecylsilane functionalized graphene oxide/silica stationary phase except for hydrophobic interaction, while only hydrophobic interaction presented between analyte and C18 commercial column. This suggests that some analytes can be better separated on the octadecylsilane functionalized graphene oxide/silica column. [ABSTRACT FROM AUTHOR]

A novel C18 functionalized graphene oxide ( GO) coated solid-phase microextraction fiber was prepared by a novel protocol. Based on the strong van der Waals interaction present in GO and abundant oxygenous groups in GO sheets, a simple layer-by-layer self-assembly method was used in the preparation process and then C18 was successfully self-assembled on GO via C-O-Si bonding. Coupled with gas chromatography, extraction performance of the fiber was tested with polycyclic aromatic hydrocarbons ( PAHs) as model analytes. The fiber not only exhibited excellent extraction efficiency and selectivity, but also showed many advantages including high rigidity, long service life and well stability toward organic solvent, acidic and alkali solutions, and high temperature. The relative standard deviations for single-fiber repeatability and fiber-to-fiber reproducibility were less than 7.26 and 17.25%, respectively. The detection limits to the PAHs were less than 0.08 μg L−1 and the calibration curves were linear in a wide range for all analytes. The as-established Solid-phase microextraction GC method was also successfully used for determination of PAHs in two real water samples. [ABSTRACT FROM AUTHOR]

A method is described for extracting and detecting the fluorescent reaction product (2′,7′-dichlorofluorescein, DCF) that is formed by reaction of reactive oxygen species (ROS) with dichlorodihydrofluorescein diacetate (DCFH-DA). DCF is extracted by using porous polyaniline nanotubes (PPN) which have a large specific surface and pore volume which favor the adsorption capacity. Additional attractive features include an appropriate pore size distribution, hydrophobic surface, and electron-attracting groups which contribute to DCF adsorption. A variety of methods was applied to characterize the morphology of PPN. Under optimal conditions and by performing DCF in 0.08-1.0 μM concentrations, the correlation coefficient of the calibration plot is 0.999. The limits of detection for standard DCF solutions is 20 nM. Compared with commercial sorbents for solid-phase extraction (SPE) such as commercially available carbon or Welchrom® C18, the use of the new sorbent results in better retraction recovery (92%) and longer reuse times (30 times). Doxorubicin and X-ray radiation were used to externally stimulate the ROS production in HepG2 and Hela cells. ROS was stabled by DCFH-DA and quantified by DCF. Following SPE, DCF was detected by HPLC and the concentration ROS was calculated.ᅟ [ABSTRACT FROM AUTHOR]

Brugada syndrome (BrS) is an inherited arrhythmogenic syndrome leading to sudden cardiac death, partially associated with autosomal dominant mutations in SCN5A, which encodes the cardiac sodium channel alpha-subunit (Nav1.5). To date some SCN5A mutations related with BrS have been identified in voltage sensor of Nav1.5. Here, we describe a dominant missense mutation (R1629Q) localized in the fourth segment of domain IV region (DIV-S4) in a Chinese Han family. The mutation was identified by direct sequencing of SCN5A from the proband’s DNA. Co-expression of Wild-type (WT) or R1629Q Nav1.5 channel and hβ1 subunit were achieved in human embryonic kidney cells by transient transfection. Sodium currents were recorded using whole cell patch-clamp protocols. No significant changes between WT and R1629Q currents were observed in current density or steady-state activation. However, hyperpolarized shift of steady–state inactivation curve was identified in cells expressing R1629Q channel (WT: V1/2 = -81.1 ± 1.3 mV, n = 13; R1629Q: V1/2 = -101.7 ± 1.2 mV, n = 18). Moreover, R1629Q channel showed enhanced intermediate inactivation and prolonged recovery time from inactivation. In summary, this study reveals that R1629Q mutation causes a distinct loss-of-function of the channel due to alter its electrophysiological characteristics, and facilitates our understanding of biophysical mechanisms of BrS. [ABSTRACT FROM AUTHOR]