Dual RNA sequencing of Helicobacter pylori and host cell transcriptomes reveals ontologically distinct host-pathogen interaction.

Helicobacter pylori is a highly successful pathogen that poses a substantial threat to human health. However, the dynamic interaction between H. pylori and the human gastric epithelium has not been fully investigated. In this study, using dual RNA sequencing technology, we characterized a cytotoxin-associated gene A (cagA)-modulated bacterial adaption strategy by enhancing the expression of ATP-binding cassette transporter-related genes, metQ and HP_0888, upon coculturing with human gastric epithelial cells. We observed a general repression of electron transport-associated genes by cagA, leading to the activation of oxidative phosphorylation. Temporal profiling of host mRNA signatures revealed the downregulation of multiple splicing regulators due to bacterial infection, resulting in aberrant pre-mRNA splicing of functional genes involved in the cell cycle process in response to H. pylori infection. Moreover, we demonstrated a protective effect of gastric H. pylori colonization against chronic dextran sulfate sodium (DSS)-induced colitis. Mechanistically, we identified a cluster of propionic and butyric acid-producing bacteria, Muribaculaceae, selectively enriched in the colons of H. pylori-pre-colonized mice, which may contribute to the restoration of intestinal barrier function damaged by DSS treatment. Collectively, this study presents the first dual-transcriptome analysis of H. pylori during its dynamic interaction with gastric epithelial cells and provides new insights into strategies through which H. pylori promotes infection and pathogenesis in the human gastric epithelium. IMPORTANCE: Simultaneous profiling of the dynamic interaction between Helicobacter pylori and the human gastric epithelium represents a novel strategy for identifying regulatory responses that drive pathogenesis. This study presents the first dual-transcriptome analysis of H. pylori when cocultured with gastric epithelial cells, revealing a bacterial adaptation strategy and a general repression of electron transportation-associated genes, both of which were modulated by cytotoxin-associated gene A (cagA). Temporal profiling of host mRNA signatures dissected the aberrant pre-mRNA splicing of functional genes involved in the cell cycle process in response to H. pylori infection. We demonstrated a protective effect of gastric H. pylori colonization against chronic DSS-induced colitis through both in vitro and in vivo experiments. These findings significantly enhance our understanding of how H. pylori promotes infection and pathogenesis in the human gastric epithelium and provide evidence to identify targets for antimicrobial therapies.

Chemical profile and difference analysis of four parts of Strobilanthes sarcorrhiza by ultrafast flow liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry and multivariate statistical analysis.

Strobilanthes sarcorrhiza (CTS) is a medicinal plant with various pharmacological effects such as tonifying kidney and anti-inflammatory. However, the chemical composition and difference of its four parts (leaves, stems, rhizomes, and root tubers) have been rarely reported. In this study, ultrafast flow liquid chromatography coupled with quadrupole-time-of-flight MS was applied to analyze the chemical profile of CTS and identify 55 compounds, including terpenoids, phenylethanol glycosides, fatty acid derivatives, chain glycosides, flavonoid glycosides, and others. Among these compounds, 34 compounds were first identified in CTS. They were mainly terpenoids, phenylethanol glycosides, fatty acid derivatives, and so forth. Multivariate statistical analysis, such as principal component analysis and orthogonal partial least squares-discriminant analysis were also used to evaluate the difference in chemical compounds from the four parts of CTS. The results showed that phenylethanol glycosides were the main compounds of the underground parts, while terpenoids were the main compounds of the aboveground parts. This study revealed the chemical diversity and similarity of CTS and suggested that the rhizomes could be used as an alternative medicinal part to improve the resource utilization of CTS.

Six polyoxotungstate-based transition metal compounds for electrochemical capacitor application and a comparative analysis of factors affecting capacitances.

Six different polyoxotungstate-based transition metal complexes were synthesized, namely [Cu5(2,2'-bpy)5(µ2-Cl)2(PO4)2(H2O)2][HPW12O40]·2H2O (1), [Cu1.5(2,2'-bpy)1.5(inic)2(H2O)1.5]3[H1.5PW12O40]2·16.25H2O (2), [Cu(2,2'-bpy)2]2[SiW12O40]·10H2O (3), [Zn(phen)3]2[PWVWVI11O40]·5H2O (4), [Zn(phen)2(H2O)]2[SiW12O40]·2H2O (5), and [Zn(2,2'-bpy)2]2[SiW12O40] (6) (2,2'-bpy = 2,2'-bipyridine, inic = isonicotinic acid, phen = 1,10-phenanthroline). Compound 1 is based on [HPW12O40]2- anions, which are accommodated within the open channels of a supramolecular network formed by novel Cu-P-Cl coordination clusters. Compound 2 is constructed from [H1.5PW12O40]1.5- and novel [Cu1.5(2,2'-bpy)1.5(inic)2(H2O)1.5]+ coordination fragments, and polyoxoanions are encapsulated within the pores created by the copper coordination fragments, resulting in a unique three-dimensional supramolecular architecture. Compound 3 is a two-dimensional structure formed through the covalent linkage between [SiW12O40]4- and [Cu(2,2'-bpy)2]2+. Compound 4 is a supramolecular architecture formed by [PWVWVI11O40]4- and [Zn(phen)3]2+ coordination fragments, while compound 5 is a supramolecular structure based on POM bi-supported Zn coordination complexes. Compound 6 is a two-dimensional framework structure constituted by [SiW12O40]4- and [Zn(2,2'-bpy)2]2+via covalent interactions. In addition, electrochemical measurement results show that the copper-based tungstate compounds 1-3 and zinc-based tungstate compounds 4-6 exhibit different performances and durabilities as electrochemical capacitors (compound 1 shows the highest specific capacitance of 94.0 F g-1 at 1.5 A g-1, whereas compound 6 maintains the best cycling stability with the capacity retention of 80.7% after 1000 cycles at 4 A g-1.). This study contributes to the development of POM-based transition metal complexes with high capacitance by providing insights into the design and synthesis process.

Special Issue: Research on Polyoxometalate Materials.

The science of polyoxometalates (POMs) has come a long way since molybdenum blue was first described in 1778 [...].

Dingxin recipe â ¢ ameliorates hyperlipidemia injury in SD rats by improving the gut barrier, particularly the SCFAs/GPR43 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Dingxin Recipe Ⅲ (DXR Ⅲ) is a traditional Chinese medicine compound used for hyperlipidemia treatment in clinical practice. However, its curative effects and pharmacological mechanisms in hyperlipidemia have not been clarified to date. AIM OF THE STUDY: Studies have demonstrated that gut barrier was strongly implicated in lipid deposition. Based on gut barrier and lipid metabolism, this study examined the effects and molecular mechanisms of DXR Ⅲ in hyperlipidemia. MATERIALS AND METHODS: The bioactive compounds of DXR Ⅲ were detected by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry, and its effects were evaluated in high-fat diet-fed rats. Specifically, the serum levels of lipids and hepatic enzymes were measured using the appropriate kits; colon and liver sections were obtained for histological analyses; gut microbiota and metabolites were analyzed by 16S rDNA sequencing and liquid chromatography-MS/MS; and the expression of genes and proteins was determined by real-time quantitative polymerase chain reaction and western blotting and immunohistochemistry, respectively. The pharmacological mechanisms of DXR Ⅲ were further explored by fecal microbiota transplantation and short-chain fatty acid (SCFAs)-based interventions. RESULTS: DXR Ⅲ treatment significantly downregulated serum lipid levels, mitigated hepatocyte steatosis and improved lipid metabolism. Moreover, DXR Ⅲ improved the gut barrier, specifically by improving the physical barrier in the colon, causing part composition changes in the gut microbiota, and increasing the serum SCFAs level. DXR Ⅲ also upregulated the expression of colon GPR43/GPR109A. Fecal microbiota transplantation from rats treated with DXR Ⅲ downregulated part hyperlipidemia-related phenotypes, while the SCFAs intervention significantly improved most of the hyperlipidemia-related phenotypes and upregulated the expression of GPR43. Moreover, both DXR Ⅲ and SCFAs upregulated the expression of colon ABCA1. CONCLUSION: DXR Ⅲ protects against hyperlipidemia by improving the gut barrier, particularly the SCFAs/GPR43 pathway.

[Preparation of monoclonal antibodies against Pinellia ternata lectin protein and establishment of double-antibody sandwich ELISA].

To determine the content of endogenous toxic substance Pinellia ternata lectin(PTL) protein in Pinelliae Rhizoma and the related processed products, this study prepared specific monoclonal antibodies against PTL by hybridoma cell technology, and established a quantitative double-antibody sandwich enzyme linked immunosorbent assay(ELISA) for PTL antigen. The detection conditions were 2.5 µg·mL~(-1) working concentration of the captured antibody and 1∶450 of the dilution multiple of detected antibody. The coating condition was staying overnight at 4 ℃. The blocking time and incubation times of antigen and detected antibody were all 90 minutes. The incubation time of horseradish peroxidase conjugated streptavidin-horseradish peroxidase(SA-HRP) was 15 minutes. The quantitative limit of the method for PTL antigen was 0.375 ng·mL~(-1). The linear range was 75.000-4 800.000 pg·mL~(-1), and R~2=0.997 1. The recovery rate was 90.0%-110.0%, and the variation coefficients of intra-test and inter-test precision were 2.0%-3.0% and 2.0%-8.5%.The content of PTL in three batches of Pinelliae Rhizoma and the related processed products was determined by the method, and the average content of PTL in Pinelliae Rhizoma was 35.42 mg·g~(-1). The average content of PTL in Pinelliae Rhizoma Praeparatum Cum Alumine, Pinelliae Rhizoma Praeparatum, and Pinelliae Rhizoma Praeparatum Cum Zingibere Et Alumine were 1.15 mg·g~(-1), 16.53 µg·g~(-1), and 122.63 ng·g~(-1), respectively, indicating that the content of PTL decreased significantly after processing. The quantitative double-antibody sandwich ELISA for PTL antigen established in this paper had good linearity, sensitive response, and high accuracy, which provided a simple and effective monitoring method for the detection of PTL content in the processing of Pinelliae Rhizoma.

[Anti-ascites effect of total saponins of Phytolaccae Radix on mice with ascites and mechanism].

This study investigated the anti-ascites effect of the total saponins of Phytolaccae Radix(PRTS) and the mechanism.H22 cell suspension was used(ip) to induce ascites in ICR male mice, and the model mice were randomized into model group, positive drug group(furosemide, 6 mg·kg~(-1)), total extract of Phytolaccae Radix(PRTE) group, and PRTS(1.29 g·kg~(-1)).Another 10 male mice were selected as the blank group.Mice in the blank group and model group were given(ig) normal saline containing 0.5% CMC-Na, and those in the positive drug group, PRTE group, and PRTS group received(ig) corresponding doses of drugs, once a day, for 8 consecutive days.The ascites volume, urine volume, and fecal water content in mice with ascites, serum levels of antidiure-tic hormone(ADH), renin in renin-angiotensin-aldosterone system(RAAS), angiotensin Ⅱ(AngⅡ), and aldosterone(ALD), expression of aquaporin(AQP)1-AQP4 in kidney, expression of AQP1, AQP3 in colon, and expression of phosphatidylinositol 3-kinase/protein kinase B(PI3 K/Akt) pathway-related proteins were detected to explore the anti-ascites mechanism of PRTS.The results showed that the PRTS can increase the urine volume and fecal water content and decrease the ascites volume of ascites mice.Moreover, PRTS significantly reduced the expression of AQP1-AQP4 in kidney and AQP1, AQP3 in colon, serum levels of renin, AngⅡ, ALD, and ADH, and the expression of p-PI3 K and p-Akt in the kidney of ascites mice.PRTS exerts anti-ascites effect by promoting urination and defecation.The mechanism is that it inhibits the activities of RAAS and ADH and suppresses the phosphorylation of PI3 K/Akt signaling pathway, thereby restricting the expression of AQPs in the kidney and colon.

First Organic-Inorganic Hybrid Compounds Formed by Ge-V-O Clusters and Transition Metal Complexes of Aromatic Organic Ligands.

Three compounds based on Ge-V-O clusters were hydrothermally synthesized and characterized by IR, UV-Vis, XRD, ESR, elemental analysis and X-ray crystal structural analysis. Both [Cd(phen)(en)]2[Cd2(phen)2V12O40Ge8(OH)8(H2O)]∙12.5H2O (1) and [Cd(DETA)]2[Cd(DETA)2]0.5[Cd2(phen)2V12O41Ge8(OH)7(0.5H2O)]∙7.5H2O (2) (1,10-phen = 1,10-phenanthroline, en = ethylenediamine, DETA = diethylenetriamine) are the first Ge-V-O cluster compounds containing aromatic organic ligands. Compound 1 is the first dimer of Ge-V-O clusters, which is linked by a double bridge of two [Cd(phen)(en)]2+. Compound 2 exhibits an unprecedented 1-D chain structure formed by Ge-V-O clusters and [Cd2(DETA)2]4+ transition metal complexes (TMCs). [Cd(en)3]{[Cd(η2-en)2]3[Cd(η2-en)(η2-µ2-en)(η2-en)Cd][Ge6V15O48(H2O)]}∙5.5H2O (3) is a novel 3-D structure which is constructed from [Ge6V15O48(H2O)]12- and four different types of TMCs. We also synthesized [Zn2(enMe)3][Zn(enMe)]2[Zn(enMe)2(H2O)]2[Ge6V15O48(H2O)]∙3H2O (4) and [Cd(en)2]2{H8[Cd(en)]2Ge8V12O48(H2O)}∙6H2O (5) (enMe = 1,2-propanediamine), which have been reported previously. In addition, the catalytic properties of these five compounds for styrene epoxidation have been assessed.

Faecal microbiome and metabolic signatures in rectal neuroendocrine tumors.

Background: The prevalence of rectal neuroendocrine tumors (RNET) has increased substantially over the past decades. Little is known on mechanistic alteration in the pathogenesis of such disease. We postulate that perturbations of human gut microbiome-metabolome interface influentially affect the development of RNET. The study aims to characterize the composition and function of faecal microbiome and metabolites in RNET individuals. Methods: We performed deep shotgun metagenomic sequencing and untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomic profiling of faecal samples from the discovery cohort (18 RNET patients, 40 controls), and validated the microbiome and metabolite-based classifiers in an independent cohort (15 RNET participants, 19 controls). Results: We uncovered a dysbiotic gut ecological microenvironment in RNET patients, characterized by aberrant depletion and attenuated connection of microbial species, and abnormally aggregated lipids and lipid-like molecules. Functional characterization based on our in-house and Human Project Unified Metabolic Analysis Network 2 (HUMAnN2) pipelines further indicated a nutrient deficient gut microenvironment in RNET individuals, evidenced by diminished activities such as energy metabolism, vitamin biosynthesis and transportation. By integrating these data, we revealed 291 robust associations between representative differentially abundant taxonomic species and metabolites, indicating a tight interaction of gut microbiome with metabolites in RNET pathogenesis. Finally, we identified a cluster of gut microbiome and metabolite-based signatures, and replicated them in an independent cohort, showing accurate prediction of such neoplasm from healthy people. Conclusions: Our current study is the first to comprehensively characterize the perturbed interface of gut microbiome and metabolites in RNET patients, which may provide promising targets for microbiome-based diagnostics and therapies for this disorder.

[Simulated processing with vinegar changes chemical structures of main terpenoids in Euphorbiae Ebracteolatae Radix].

This study aims to explore the chemical structure transformation mechanisms of the main terpenoids in the effective fraction of Euphorbiae Ebracteolatae Radix(EER) during the processing with vinegar. The terpenoids including ent-11α-hydroxyabicta-8(14),13(15)-dien-16,12-olide(HAO), jolkinolide B(JNB), fischeria A(FA), and eupractenoid A(EA) were heated at 160 ℃ with 6% acetic acid for 40 min, and then LC-MS/MS was employed to analyze the structural transformation rules of the terpenoids. Further, we analyzed the changes in the relative content of the four compounds and their transformation products in raw and vinegar processed EER to verify the transformation rules during the simulated processing with vinegar. In addition, JNB and FA were processed with single heating, heating with water or heating with acetic acid. We then employed HPLC to compare the content of these two terpenoids and their transformation products before and after processing, so as to investigate the effect of different processing methods on chemical structure transformation. The results showed that the lactone ring of the abietane-type diterpenoids HAO and JNB and the norditerpene lactone FA were opened by heating with acetic acid. When there were hydroxyl groups in the structures, terpenoids were esterized to esters and oxidized to form carbonyl groups. When there was epoxy ring in the structures, ring opening reaction was easy to occur. During the heating with acetic acid, the heterodimeric diterpenoid EA underwent the cleavage of ether bond to produce the rosane-type diterpenoid euphebracteolatin A(EHTA) and another abietane-type diterpenoid. The changes in the relative content of terpenoids and their transformation products in raw and vinegar-processed EER were basically consistent with those of simulated processing of components with vinegar. The HPLC results revealed that the effect of different simulated processing methods on structural transformation varied. Heating with acid can change JNB and FA into new components. Heating with water can also promote the structural transformation, with the efficiency obviously lower than that of heating with acid. Direct heating had no influence on the structure of JNB, while it significantly reduced the relative content of FA. The components treated with direct heating did not produce the products like those of the heating with acid. These results indicated that vinegar plays a key role in the structural transformation of diterpenoids during the processing of EER with vinegar. The structural transformation of diterpenoids in EER during the processing with vinegar may be the material basis for vinegar processed EER to reduce toxicity and preserve effect.

A combination approach using two functionalized magnetic nanoparticles for speciation analysis of inorganic arsenic.

Mercapto- and amino-functionalized magnetic nanoparticles, Fe3O4@SiO2@MPTMS (SMNPs-MPTMS) and Fe3O4@SiO2@APTES (SMNPs-APTES), have been applied as magnetic solid-phase extraction (MSPE) sorbents to directly extract arsenite (As(III)) and arsenate (As(V)) respectively, followed by inductively coupled plasma-mass spectrometry (ICP-MS) detection. Various MSPE parameters were optimized including dose of magnetic adsorbent, pH of sample solution, loading and elution conditions of analytes, adsorption capacity and reusability of SMNPs-MPTMS and SMNPs-APTES for As(III) and As(V) respectively. Under the optimized MSPE conditions, this combined scheme possesses excellent selectivity and strong anti-interference ability without any oxidation or reduction prior to capture of these two species. It is found that with a 25-fold enrichment factor, the limits of detection of As(III) and As(V) were 23.5 and 10.5 ng L-1, respectively. To verify the reliability of the proposed protocol, a certified reference material of environmental water was analyzed, and the results for inorganic arsenic species were in close agreement with the certified values. The applicability of the combination strategy for speciation analysis of inorganic arsenic was evaluated in spiked tap, river, lake and rain water samples. Good recoveries of 89%-96% and 90%-102% were achieved for As(III) and As(V), respectively, with the relative standard deviation ranges of 3.2%-8.0% and 2.5%-7.6%. Through the characterization of functionalized magnetic nanoparticles and the optimization of MSPE experiment, it is confirmed that the existence of mercapto and amino groups on SMNPs-MPTMS and SMNPs-APTES sorbents are responsible for the extraction of As(III) and As(V), respectively, via coordination and electrostatic interactions.

CircSOD2: A Novel Regulator for Smooth Muscle Proliferation and Neointima Formation.

OBJECTIVE: Vascular smooth muscle cell (SMC) proliferation contributes to neointima formation following vascular injury. Circular RNA-a novel type of noncoding RNA with closed-loop structure-exhibits cell- and tissue-specific expression patterns. However, the role of circular RNA in SMC proliferation and neointima formation is largely unknown. The objective of this study is to investigate the role and mechanism of circSOD2 in SMC proliferation and neointima formation. Approach and Results: Circular RNA profiling of human aortic SMCs revealed that PDGF (platelet-derived growth factor)-BB up- and downregulated numerous circular RNAs. Among them, circSOD2, derived from back-splicing event of SOD2 (superoxide dismutase 2), was significantly enriched. Knockdown of circSOD2 by short hairpin RNA blocked PDGF-BB-induced SMC proliferation. Inversely, circSOD2 ectopic expression promoted SMC proliferation. Mechanistically, circSOD2 acted as a sponge for miR-206, leading to upregulation of NOTCH3 (notch receptor 3) and NOTCH3 signaling, which regulates cyclin D1 and CDK (cyclin-dependent kinase) 4/6. In vivo studies showed that circSOD2 was induced in neointima SMCs in balloon-injured rat carotid arteries. Importantly, knockdown of circSOD2 attenuated injury-induced neointima formation along with decreased neointimal SMC proliferation. CONCLUSIONS: CircSOD2 is a novel regulator mediating SMC proliferation and neointima formation following vascular injury. Therefore, circSOD2 could be a potential therapeutic target for inhibiting the development of proliferative vascular diseases.

Janus Kinase 3 Deficiency Promotes Vascular Reendothelialization-Brief Report.

[Figure: see text].

Preparation of a novel amino functionalized ion-imprinted hybrid monolithic column for the selective extraction of trace copper followed by ICP-MS detection.

In this work, a novel amino functionalized Cu(II) ion-imprinted organic-inorganic hybrid monolithic column (Cu(II)-IIHMC) was prepared via one-pot co-condensation and the combination of sol-gel and ion-imprinting techniques in a fused capillary. The Cu(II)-IIHMC was used as solid phase microextraction (SPME) matrix followed by inductively coupled plasma-mass spectrometry (ICP-MS) for the analysis of trace Cu(II). The prepared Cu(II)-IIHMC has good mechanical strength, stable imprinting sites and homogeneous structure of network skeleton with large flow-through pores by optimizing the synthesis process. Under the optimized conditions, the Cu(II)-IIHMC can selectively adsorb Cu(II) with the adsorption capacity of 3.13 mg g-1. With enrichment factor of 10-fold, the calibration curve was established in the range of 0.05-50 µg L-1 with r2 of 0.9992 and the detection limit was 0.008 µg L-1 for Cu(II). Compared with the non-imprinted hybrid monolithic column (Cu(II)-NIHMC), the Cu(II)-IIHMC possesses better selectivity, anti-interference ability and adsorption capacity. The Cu(II)-IIHMC can specifically capture the target ion in the presence of competitive ions, with the selectivity coefficients exceeding 39.4. The protocol was validated by analyzing Certified Reference Materials of standard sediment, soil and iron ore, and the results were in good agreement with certified values. Moreover, the proposed in-tube SPME procedure can not only preconcentrate trace Cu(II), but also effectively reduce the matrix effect and powerfully eliminate the interference from the main metals in real samples. Therefore, the developed SPME-ICP-MS method with facile preparation, specific selectivity, high sensitivity and efficient analysis, was applied in the determination of trace Cu(II) in environmental and mineral samples with the recoveries of 89.8-111.8% in all spiked samples.

ADAR1 deficiency protects against high-fat diet-induced obesity and insulin resistance in mice.

Obesity is an important independent risk factor for type 2 diabetes, cardiovascular diseases, and many other chronic diseases. The objective of this study was to determine the role of adenosine deaminase acting on RNA 1 (ADAR1) in the development of obesity and insulin resistance. Wild-type (WT) and heterozygous ADAR1-deficient (Adar1+/-) mice were fed normal chow or a high-fat diet (HFD) for 12 wk. Adar1+/- mice fed with HFD exhibited a lean phenotype with reduced fat mass compared with WT controls, although no difference was found under chow diet conditions. Blood biochemical analysis and insulin tolerance test showed that Adar1+/- improved HFD-induced dyslipidemia and insulin resistance. Metabolic studies showed that food intake was decreased in Adar1+/- mice compared with the WT mice under HFD conditions. Paired feeding studies further demonstrated that Adar1+/- protected mice from HFD-induced obesity through decreased food intake. Furthermore, Adar1+/- restored the increased ghrelin expression in the stomach and the decreased serum peptide YY levels under HFD conditions. These data indicate that ADAR1 may contribute to diet-induced obesity, at least partially, through modulating the ghrelin and peptide YY expression and secretion.NEW & NOTEWORTHY This study identifies adenosine deaminase acting on RNA 1 as a novel factor promoting high-fat diet-induced obesity, at least partially, through modulating appetite-related genes ghrelin and PYY.

Carboxyl-functionalized hybrid monolithic column prepared by "thiol-ene" click reaction for noninvasive speciation analysis of chromium with inductively coupled plasma-mass spectrometry.

A novel carboxyl-functionalized hybrid monolithic column was developed based on "thiol-ene" click reaction via "one-pot" by choosing mercaptosuccinic acid, γ-methyl methacrylate trimethoxysilane and tetramethoxysilane as reaction monomers. The design of the hybrid monolithic column was assisted by the comparison in computational simulation with existing carboxyl-functionalized materials. The characterization by scanning electron microscopy, energy dispersive X-ray spectroscopy, N2 adsorption-desorption measurement, Fourier-transform infrared spectroscopy and elemental analysis showed that the carboxyl-functionalized material has the advantages of good permeability and high mechanical strength. Then, we used the prepared carboxyl-hybrid monolith column as solid phase microextraction adsorbent for separation of trace inorganic chromium species. Under pH 4.5, the hybrid monolith column can selectively enrich Cr(III) without adsorbing Cr(VI) and afterwards, Cr(III) can be eluted by 1.0 mol L-1 HCl. The chromium speciation separation method based on carboxyl-hybrid monolith column followed by inductively coupled plasma-mass spectrometry possessed the merits of facile preparation, low cost, simple and mild extraction condition, and sensitive detection, which has been successfully applied to the separation, enrichment and detection of inorganic chromium in environmental waters.

Syntheses, characterization and properties of two new dodeca-niobates presenting unprecedented features.

Two new dodeca-niobate materials, K3[Nb2O2][H7SiNb12O40]·16H2O (1) and [Cu(en)2]9[(VNb12V1.69Nb0.31O42en0.31)2]·20.69H2O (2) (en = ethylenediamine), have been obtained under hydrothermal conditions and characterized by IR, UV-Vis, XRD, and single crystal X-ray diffraction analysis. Single crystal X-ray analysis reveals that compound 1 presents a reasonable bridging layer structure model and that K plays a great role in the three-dimensional structure. Compound 2 is the first capped Keggin POM with organic ligand chelating the capping atom. The photocatalytic hydrogen evolution and styrene epoxidation catalytic properties of the two compounds were also assessed. Additionally, compound 1 is also a good photocatalyst to degrade RhB.

In-tube solid-phase microextraction with a hybrid monolithic column for the preconcentration of ultra-trace metals prior to simultaneous determination by ICP-MS.

The preparation of an amino-functionalized hybrid monolithic column (TEOS-co-AEAPTES) via one-pot co-condensation of tetraethoxysilane (TEOS) and N-(ß-aminoethyl)-γ-aminopropyltriethoxysilane (AEAPTES) in a capillary is descibed. It was used as solid-phase microextraction (SPME) matrix followed by inductively coupled plasma-mass spectrometry (ICP-MS) for determination of trace metals. Under optimum conditions, the amino-functionalized SPME material can simultaneously retain Cu(II), Zn(II), Au(III), and Pb(II) with adsorption capacities of 148, 60, 81, and 64 µg m-1, respectively. Subsequently, these four metal ions can be quantitatively eluted using 1 mol L-1 HNO3 containing 1% thiourea. The retention mechanism of Cu(II), Zn(II), Au(III), and Pb(II) on the amino-functionalized hybrid monolith was explained as the combination of electrostatic and coordination interactions. With a 10-fold enrichment factor, the calibration curves were established in the range 0.5-100 µg L-1 with linear correlation coefficients above 0.9943 and the limits of quantitation were 0.05 µg L-1 for four target analytes. The limits of detection were 0.006, 0.012, 0.004, and 0.007 µg L-1 for Cu(II), Zn(II), Au(III), and Pb(II), respectively. The protocol was validated by analyzing Certified Reference Materials including standard sediment, soil, and nickel ore, and the results were in good agreement with their certified values. The relative standard deviations of the method were in the range 0.22-17.6%. The recoveries of the four metal ions in spiked samples were in the range 88.0-113.8%. Compared to direct ICP-MS determination, the proposed in-tube SPME procedure can effectively eliminate the interference from complex matrix, especially from those ores with very high content of main metal to improve the accuracy of analysis. Therefore the method is suitable for the simultaneous determination of ultra-trace Cu(II), Zn(II), Au(III), and Pb(II) in environmental and mineral samples. Graphical abstract The preparation of the TEOS-co-AEAPTES monolithic column and the SPME procedure of Cu(II), Zn(II), Au(III), and Pb(II).

Development of a novel amine- and carboxyl-bifunctionalized hybrid monolithic column for non-invasive speciation analysis of chromium.

A novel amine- and carboxyl-bifunctionalized organic-inorganic hybrid monolithic column (A&C-HMC) was synthesized via one-pot co-condensation of N-(2-aminoethyl)-3-aminopropyltriethoxysilane, carboxyethylsilanetriol sodium salt and tetramethoxysilane with cetyltrimethylammonium bromide and polyethylene glycol 6000 as binary porogens in this work. The introduction of the binary porogens controllably improved the morphology and pore structure of A&C-hybrid monolith (HM) and made the active sites of amine and carboxyl groups more prolific, compared with the monolith prepared with either of porogens. It is found that Cr(VI) and Cr(III) can be selectively adsorbed on A&C-HM under different pH ranges, and eluted by aqueous nitric acid solution completely. The A&C-HMC was used as needle-solid phase microextraction (SPME) matrix for direct separation and enrichment of inorganic chromium species coupled with inductively coupled plasma mass spectrometer without any oxidation/reduction treatment. Various parameters of SPME operation and analytical performance were investigated systematically, and the adsorption mechanism was also discussed and explained in depth. In view of the advantages of facile preparation, low cost, excellent speciation selectivity and high adsorption capacity to Cr(VI) and Cr(III), the A&C-HMC based SPME protocol is a promising alternative for non-disturbed speciation analysis of inorganic chromium in real environmental water samples.

[Qualitative evaluation of Forsythia suspensa by HPLC-PDA fingerprint combined with UFLC-Q-TOF-MS qualitative identification].

The analysis of Forsythia suspensa was performed on Waters Symmetry C18 column( 4. 6 mm×250 mm,5 µm) and mobile phase was methanol( A)-0. 1% formic acid aqueous solution( B) with the elution gradient. Column temperature was maintained at 30℃,and the flow rate was 1. 0 m L·min-1 with detection wavelength 265 nm. The HPLC-PDA fingerprint of F. suspensa was optimized.Chemical constituents in F. suspensa were analyzed by UFLC-Q-TOF-MS in positive and negative ion mode. The quality of 48 batches of F. suspensa from different habitats,processing methods and specifications was evaluated by similarity evaluation and cluster analysis.The 18 common peaks were confirmed. The similarity of F. suspensa from different habitats was more than 0. 98,and 56 chemical constituents were identified. Different processing methods had great influence on the quality of F. suspensa. Compared with boiled and direct drying,the quality of F. suspensa processed by sun-drying was obviously decreased. The similarity was about 0. 58. Different specifications of F. suspensa also had obvious distinction,and the similarity was about 0. 78. The effective components of grown F. suspensa,such as forsythoside A and phillyrin,were significantly reduced. The results of cluster analysis were basically consistent with the results of similarity evaluation. The establishment of fingerprint and the recognition of chemical pattern of F. suspensa can provide a more comprehensive reference for the quality control of herbs.