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A sensitive and accurate chemiluminescence (CL) method was developed for one-step determination of diphenyl ether herbicides at trace level with nitrofen (2,4-dichlorophenyl-p-nitrophenyl ether) as a model analyte. Candida rugosa lipase (CRL) was immobilized on a nanocarrier of amine-linked covalent organic framework (named as COF-300-AR) through a self-assembly strategy. The formed nanocomposite of COF-300-AR@CRL owns dual enzymatic catalytic activities. It can directly catalyze luminol-dissolved oxygen reaction to produce an intense CL emission by virtue of oxidase mimic activity of COF-300-AR but also effectively decompose nitrofen to release phenolic compounds by the immobilized CRL. The released phenolic compounds own strong reducing capacity and in turn decrease the CL signal sharply. Under the optimal conditions, the decreased CL intensity presents a good linear response to nitrofen concentration in the 0.02–50.0 μM range. The limit of detection (LOD, 3sb/S) is 11 nM and the precision is 2.0% for replicate measurements of 50.0 nM nitrofen solution (n = 11). This method has the advantages of rapid analytical efficiency, good selectivity, satisfactory stability, and recyclability. Recovery experiments were conducted on spiked vegetable and fruit samples with the recoveries falling in the range 90.0–107.0%. [ABSTRACT FROM AUTHOR]

Magnetoencephalography (MEG) records the brain magnetic field signals. Optically pumped magnetometer (OPM) is a novel technology for MEG measurement in its infancy, it is essential to demonstrate its performance on the key neuroimaging features, such as phase-locking value. In this paper, the inter-trial phase-locking value (ITPL) and inter-region phase-locking value (IRPL) were analyzed by simulation and measurement experiments using OPM-MEG, the superconducting quantum interference device (SQUID) data was applied for the compare. The simulation results show that OPMs could offers good characterization on phase-locking value under higher noise intensity. In experiments, the similarity ratios of ITPL and IRPL between OPM-MEG and SQUID-MEG are >0.90. The significantly increased frequencies of IRPL in pure tone and somatosensory stimulation are at about 10–20 Hz and 8–13 Hz respectively, with Spearman correlation coefficients >0.7. The results provide experimental evidence of the ability of OPM-MEG for measuring phase synchronization and functional connectivity on sensor signals. [Display omitted] • OPM offers good characterization on phase-locking value under higher noise level. • With SNR increased within 0–15 dB, phase-locking value increases linearly. • This is the first study to measure IRPL on sensor signals using OPM. • The correlation of IRPL is >0.7 between OPM and SQUID. [ABSTRACT FROM AUTHOR]

• Screening of CCL17 and CCL19 by WGCNA combined with differential genes is the key gene for Echinococcus multilocularis infection. • CCL17 and CCL19 may be signs of the progress of Echinococcus infection. • The expression of CCL17 and CCL19 and macrophage marker F4/80 were also up-regulated. Alveolar echinococcosis (AE) represents one of the deadliest helminthic infections, characterized by an insidious onset and high lethality. This study utilized the Gene Expression Omnibus (GEO) database, applied Weighted Correlation Network Analysis (WGCNA) and Differential Expression Analysis (DEA), and employed the Matthews Correlation Coefficient (MCC) to identify CCL17 and CCL19 as key genes in AE. Immunohistochemistry and immunofluorescence co-localization techniques were used to examine the expression of CCL17 and CCL19 in liver tissue lesions of AE patients. Additionally, a mouse model of multilocular echinococcus larvae infection was developed to study the temporal expression patterns of these genes, along with liver fibrosis and inflammatory responses. The in vitro model simulating echinococcal larva infection mirrored the hepatic microenvironment post-infection with multilocular echinococcal tapeworms. Quantitative RT-PCR analysis showed that liver fibrosis occurred in AE patients, with proximal activation and increased expression of CCL17 and CCL19 over time post-infection. Notably, expression peaked during the late stages of infection. Similarly, F4/80, a macrophage marker, exhibited corresponding trends in expression. Upon stimulation of normal hepatocytes by vesicular larvae in cellular experiments, there was a significant increase in CCL17 and CCL19 expression at 12 h post-infection, mirroring the upregulation observed with F4/80. CCL17 and CCL19 facilitate macrophage aggregation via the chemokine pathway and their increased expression correlates with the progression of infection, suggesting their potential as biomarkers for AE progression. [ABSTRACT FROM AUTHOR]

The optimal therapeutic options, adding locoregional therapy (LRT) to systemic therapy (ST) or not, for patients with oligometastatic breast cancer (OMBC) have not been fully elucidated. Hence, we designed a retrospective observational study which enrolled patients with measurable extracranial OMBC having less than 5 metastatic lesions not necessarily in the same organ. We retrospectively reviewed a total of 199 patients diagnosed with extracranial OMBC, including 28 receiving ST followed by LRT (ST to LRT group), 44 receiving LRT followed by ST (LRT to ST group), and 127 receiving ST alone (ST alone group). After a median follow-up of 28.7 months, patients receiving both ST and LRT had a significantly better prognosis than those receiving ST alone: the median progression-free survival (PFS) was 16.3, 14.0, and 9.3 months (P < 0.001) and the median overall survival (OS) was 39.8, 70.5, and 26.7 months (P < 0.001) in the ST to LRT, LRT to ST, and ST alone groups, respectively. Sequence of ST and LRT had no significant impact on survival among patients receiving both. Further exploratory analysis identified ST plus LRT as an independent predictor for longer PFS. In conclusion, we demonstrated that adding LRT to ST was associated with survival benefits for patients with OMBC, and further prospective studies were warranted. [ABSTRACT FROM AUTHOR]

• In AE, MTLN is identified as a biomarker of M2 macrophages, which mediates the energy metabolism of macrophages. • The mouse model showed that MTLN was related to M2 macrophages. • Cell experiments showed that the expression of MTLN increased with time. The pathogen of alveolar echinococcosis (AE) is Echinococcus multilocularis (E. multilocularis), which has the characteristics of diffuse infiltration and growth and has a high mortality rate. At present, the role of macrophages in AE infection has attracted more and more attention, but the new biomarkers and polarization mechanisms of macrophages are rarely studied. In this study, CIBERSORT and WGCNA algorithms were used to establish a weighted gene co-expression network, and MTLN was identified as a biological marker of M2-type macrophages, which participated in energy metabolism of macrophages and mediated inflammatory response, but the role of MTLN in AE was not studied. In this study, liver tissue samples from AE patients were collected and immunofluorescence co-localization showed the relationship between MTLN and macrophage distribution. E. multilocularis infected mouse model was established to analyze the expression of MTLN, liver fibrosis, and inflammatory reaction after E. multilocularis infection. The cell experiment simulated the liver microenvironment of E. multilocularis infected human body and analyzed the expression of MTLN by QRT-PCR and western blot in vitro. The data showed that liver fibrosis occurred in AE patients, and MTLN was activated near the focus. After E. multilocularis infected mice, the expression of MTLN increased with time. In the cell experiment, after the antigen of E. multilocularis protoscolex stimulated normal liver cells, the expression of MTLN increased 48 h, at this time, M2 was up-regulated and M1 was down-regulated. Therefore, MTLN may be the key gene to regulate the polarization of M2 macrophages and cause fibrosis. [ABSTRACT FROM AUTHOR]

A chemiluminescence (CL) sensor was constructed for the one-step determination of glucose. Glucose oxidase (GOx) was successfully encapsulated into Zn-doped zeolitic imidazolate framework-67 (Zn–ZIF–67) via a simple one-pot strategy. The as-prepared GOx@Zn–ZIF–67 nanocomposite can trigger cascade reactions of glucose oxidation to generate H2O2 and H2O2-mediated luminol reaction to give an intense CL emission. The sensor responds linearly to glucose in the 20.0–400.0 μmol·L–1 range with a limit of detection (LOD) of 4.7 μmol·L–1. Eleven replicated measurements of 200.0 μmol·L–1 glucose solution gives a relative standard deviation (RSD) of 1.7%. The sensor exhibits good selectivity and stability and was successfully applied to the determination of glucose in real human serum samples. Schematic representation of one-step determination of serum glucose with GOx@Zn–ZIF–67 nanocomposite triggering cascade reactions between luminol and glucose. [ABSTRACT FROM AUTHOR]

Multivariate pattern analysis (MVPA) has played an extensive role in interpreting brain activity, which has been applied in studies with modalities such as functional Magnetic Resonance Imaging (fMRI), Magnetoencephalography (MEG) and Electroencephalography (EEG). The advent of wearable MEG systems based on optically pumped magnetometers (OPMs), i.e., OP-MEG, has broadened the application of bio-magnetism in the realm of neuroscience. Nonetheless, it also raises challenges in temporal decoding analysis due to the unique attributes of OP-MEG itself. The efficacy of decoding performance utilizing multimodal fusion, such as MEG-EEG, also remains to be elucidated. In this regard, we investigated the impact of several factors, such as processing methods, models and modalities, on the decoding outcomes of OP-MEG. Our findings indicate that the number of averaged trials, dimensionality reduction (DR) methods, and the number of cross-validation folds significantly affect the decoding performance of OP-MEG data. Additionally, decoding results vary across modalities and fusion strategy. In contrast, decoder type, resampling frequency, and sliding window length exert marginal effects. Furthermore, we introduced mutual information (MI) to investigate how information loss due to OP-MEG data processing affect decoding accuracy. Our study offers insights for linear decoding research using OP-MEG and expand its application in the fields of cognitive neuroscience. [ABSTRACT FROM AUTHOR]

One of the primary reasons for the successful patriotization of Echinococcus multilocularis in patients is its ability to induce host immune tolerance. This study examined the expression of the immunosuppressive Tim-3/Galectin-9 pathway, CD8+T cells, and related factors in AE patients. The aim was to analyze the relationship between the Tim-3/Galectin-9 pathway and CD8+T cells in this disease and further understand the mechanism of immune tolerance induced by cystic echinococcosis. Using flow cytometry, we evaluated the expression of CTL, CD8+CD28-T cells, CD8+CD28 + IFN-γ + T cells, CD8+CD28+perforin + T cells, CD8+CD28+granzyme B + T cells, CD8+CD28-IL-10 + T cells, CD8+CD28-TGF-β+T cells, and Tim-3 expression on CD8+T cells in the peripheral blood of control (n = 30) and AE patients (n = 33). qRT-PCR was used to measure CD107a and Tim-3/Galectin-9 mRNA levels in PBMCs from the control and AE groups. Immunohistochemistry was employed to detect IL-10, TGF-β, and Tim-3/Galectin-9 expressions in the infected livers of AE patients. AE patients exhibited a significant decrease in peripheral blood CTL ratio (P < 0.001) and an increase in CD8+CD28+IFN-γ+T cell ratio (P < 0.001). No significant changes were observed in the ratios of CD8+CD28+perforin + T cells (P = 0.720) and CD8+CD28+granzyme B + T cells (P = 0.051). The proportions of CD8+CD28-T cells (P < 0.001), CD8+CD28-IL-10 + T cells (P < 0.001), and CD8+CD28-TGF-β+T cells (P < 0.001) were notably higher than in the control group. The expression of Tim-3 on CTL and CD8+CD28-T cells in AE patients was significantly upregulated (P < 0.001, P < 0.001). AE patients displayed a substantial decrease in peripheral blood PBMC CD107a mRNA levels (P < 0.001) and significant elevations in Tim-3/Galectin-9 mRNA levels (P < 0.001, P < 0.001). A negative correlation was observed between CD107a mRNA levels and both Tim-3 (r^2 = 0.411, P < 0.001) and Galectin-9 (r2 = 0.180, P = 0.019) mRNA levels. Expressions of IL-10 (P < 0.001), TGF-β (P < 0.001), and Tim-3/Galectin-9 (P < 0.001, P < 0.001) in AE patient-infected livers were significantly higher than in uninfected regions. IL-10 and TGF-β expressions showed a positive correlation with Tim-3/Galectin-9. This study suggests that the high expression of Tim-3 on CD8+T cell surfaces in AE patients might promote an increase in CD8+CD28-T cells and related factors, while suppressing CTL and related factor expressions. This potentially induces the onset of immune tolerance, which is unfavorable for the clearance of Echinococcus multilocularis in patients, leading to the exacerbation of persistent infections. [Display omitted] • We found that high expression of Tim-3 on the surface of CD8+ Treg cells in AE patients. • And the Tim-3/galactose lectin-9 pathway promotes the expression of the transcription factor Foxp3 and the inhibitory cytokines IL-10 and TGF-β. • This study confirmed that the expression of Tim-3/galectin −9 pathway can promote the expression of transcription factor Foxp3 and inhibitory cytokines IL-10 and TGF-β. This phenomenon may eventually lead to the aggravation of infection. • It was mainly confirmed by flow cytometry. • The tissues of patients with hepatic hydatid disease were collected and analyzed in detail. [ABSTRACT FROM AUTHOR]

Key message: Powdery mildew resistance gene PmXNM, originated from the Chinese wheat landrace Xiaonanmai, was delimited to a 300.7-kb interval enriched with resistance genes. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a globally devastating disease threatening the yield and quality of wheat worldwide. The use of broad-spectrum disease resistance genes from wheat landraces is an effective strategy to prevent this pathogen. Chinese wheat landrace Xiaonanmai (XNM) was immune to 23 tested Bgt isolates at the seedling stage. The F1, F2, and F2:4 progenies derived from the cross between XNM and Chinese Spring (CS) were used in this study. Genetic analysis revealed that powdery mildew resistance in XNM was controlled by a single dominant gene, temporarily designated PmXNM. Bulked segregant analysis and molecular mapping delimited PmXNM to the distal terminal region of chromosome 4AL flanked by markers caps213923 and kasp511718. The region carrying the PmXNM locus was approximately 300.7 kb and contained nine high-confidence genes according to the reference genome sequence of CS. Five of these genes, annotated as disease resistance RPP13-like proteins 1, were clustered in the target region. Haplotype analysis using the candidate gene-specific markers indicated that the majority of 267 common wheat accessions (75.3%) exhibited extensive gene losses at the PmXNM locus, as confirmed by aligning the targeted genome sequences of CS with those of other sequenced wheat cultivars. Seven candidate gene-specific markers have proven effective for marker-assisted introgression of PmXNM into modern elite cultivars. [ABSTRACT FROM AUTHOR]

Climate changes, including sea level rise (SLR) and typhoon intensification (TI), have been widely accepted in coastal communities and significantly affect coastal engineering. In this work, an integrally-coupled tide-surge-wave model was developed to simulate storm tides and waves around the coastal area of Qingdao. The model was validated with observed data under historical typhoon events. The simulated results illustrate that tides change obviously at most representative stations within Jiaozhou Bay. Meanwhile, the effect of SLR on astronomical tide in the flood and the ebb period is more significant than that of the peak tide period. Further investigations reveal that SLR and TI affect storm tides and waves in different ways and the influences are different within Jiaozhou Bay and along the open coast. Besides, the combined effects of SLR and TI on peak storm tides and wave heights are remarkable, which are not a simply linear superposition and present a spatially non-uniform and non-liner pattern. Therefore, it is essential to adopt the coupled model to estimate the possible maximum risk of storm surges and waves around the coastal area of Qingdao. Taking SLR and TI into consideration, the peak of elevation near shore could experience a significant amplification in the future. • An integrally-coupled tide-surge-wave model is developed. • Storm surge and wave modeling in the coastal area of Qingdao is carried out. • The differences of storm surge between coupled and uncoupled models are analyzed. • The effects of climate changes on tides, storm surges and waves are investigated in the study area. • The possible maximum risk of storm surges and waves in 2100 is estimated around the coastal area of Qingdao. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluorescent TpPa-1@FL was prepared with a post-synthetic modification strategy. • TpPa-1@FL was employed an energy acceptor to construct CRET system. • The CRET signal was enhanced by bovine serum albumin. • The CRET system can determine H 2 O 2 and uric acid in biological samples. A simple and feasible strategy was developed for the preparation of fluorescent covalent organic frameworks (COFs) TpPa-1@FL. The TpPa-1–1@FL was prepared via a self-assembly strategy by soaking non-fluorescent COFs TpPa-1 into strong fluorescent fluorescein (FL) solution. A chemiluminescence resonance energy transfer (CRET) system was constructed by the combination strong fluorescent TpPa-1@FL with TCPO-hydrogen peroxide (H 2 O 2) reaction. The chemiluminescence (CL) signal of the system was further improved by the addition of bovine serum albumin (BSA). The CRET system can determine H 2 O 2 with a linear range response from 5.0 µmol/L to 20.0 mmol/L and a detection limit of 1.1 µmol/L. The CRET system was further exploited for indirect detection of uric acid with coupling of uricase. A good linear relationship was obtained for uric acid in the 10.0–400.0 µmol/L concentration range with a detection limit of 3.8 µmol/L. The practicability of this method was assessed by the determination of uric acid in real samples of human serum and urine. [ABSTRACT FROM AUTHOR]

Abstract: In this work, 3,4-ethylenedioxythiophene (EDOT) emulsion is prepared by ultrasonication agitation and poly(3,4-ethylenedioxythiophene) (PEDOT) coating is fabricated on a stainless steel wire by electrochemical method from a 0.10M sodium dodecylbenzenesulfonate aqueous solution containing EDOT. The coating is characterized by scanning electron microscopy and Fourier transform infrared spectrophotometry, and it presents cauliflower-like structure. When the resulted PEDOT/steel fiber is used for the headspace solid phase-microextraction of some esters (i.e. methyl anthranilate, dimethyl phthalate, ethyl-o-aminobenzoate, methyl laurate and diethyl phthalate) and their GC detection, the limits of detection (LOD) are ca. 7.8–31ngL−1 (S/N=3) and the linear ranges are 0.25–800μgL−1. The fiber shows high thermal stability (up to 320°C), good reproducibility and long lifetime (more than 183 times). It also has good chemical stability. After it is immersed in acid, alkali and dichloromethane for 4h its extraction efficiency remains almost unchanged. Besides esters the fiber also exhibits high extraction efficiency for alcohols and aromatic compounds. [Copyright &y& Elsevier]

Covalent organic frameworks (COFs) are considered to be a promising support material for catalyst due to their highly ordered porous structure. Here, a core-shell structured Fe 3 O 4 magnetic covalent organic framework (Fe 3 O 4 @COF) was synthesized and employed to provide basic sites for immobilization of gold nanoparticles (AuNPs). The AuNPs was in-situ immobilized on the shell of Fe 3 O 4 @COF via a citrate reducing method. The Fe 3 O 4 @COF-AuNP had convenient magnetic separability and exhibited excellent mimicking peroxidase-like activity in catalyzing chemiluminescence (CL) reaction of luminol with hydrogen peroxide (H 2 O 2). With acetylcholine chloride (ACh) as substrate of acetylcholinesterase (AChE), a CL method was exploited for sensitive detection of organophosphorus pesticide triazophos due to its irreversible inhibiting effect on the AChE activity and subsequently influences the production of H 2 O 2 under the condition of choline oxidase (ChOx). This method gave a good linearity for triazophos in the range of 5.0–300.0 nmol L−1, and a limit of detection (LOD) of 1 nmol L−1 was acquired. The applicability of this method was verified by the determination of triazophos in different spiked vegetable samples. [Display omitted] • Core-shell structured magnetic covalent organic framework is prepared for the immobilization of gold nanoparticles. • Fe 3 O 4 @COF-AuNP exhibits excellent mimicking peroxidase-like activity. • Triazophos can be sensitive detected through hindering enzymatic H 2 O 2 production. • Fe 3 O 4 @COF-AuNP can be recycled and shows efficient reusability. [ABSTRACT FROM AUTHOR]

Pd membranes act in an important role in H2 purification and H2 production in membrane reactors. Pd-Ag alloy membranes fabricated by consecutive electroless- and electroplating process on alumina tubes exhibited good stability under stringent heating/cooling cycles at a ramp rate of 10 K/min, imitating practical fast initiation or emergency shutdown conditions. Bilayer Pd-Ag membranes can form dense and uniform alloy after thermal treatment for 24 h at 823 K under H2 atmosphere, despite a porous structure due to the development of liquid-like properties above Tamman temperature to enforce the migrativity. On the contrary, alloying under N2 atmosphere resulted in a Pd-enriched layer. This led to a lower H2 flux but superior thermal stability compared to that alloying under H2 atmosphere. The trilayer approach of electroless-plated Pd, electro-polated Ag and electroless-plated Pd is not suitable to achieve homogeneous Pd-Ag alloys, which, on the other hand, presented the occurrence of a small gap between top Pd layer and middle Ag layer, probably due to insufficient wetting during plating process. An on-site repair treatment in analogous to MOCVD (Metal-organic Chemical Vapor Deposition) process was first proposed to extend the lifetime of Pd-Ag membrane, i.e., by vaporizing, and subsequent decomposition of Ag(OOCC2F5) powders to "preferentially" block the pinholes under vacuum and at working temperature of ca. 473–673 K, which effectively reduced the N2 flux by 57.4% compared to the initial value. The H2 flux, however, declined by 16.7% due to carbon deposition on the membrane surface, which requires further investigation. This approach shows some potential for on-site repair without disassembly or cooling to room temperature. [ABSTRACT FROM AUTHOR]

Background: Despite significant survival improvement in human epidermal growth factor receptor 2 (HER2) blockade for HER2-positive breast cancer, resistance to anti-HER2 remains inevitable. Subsequent anti-HER2 with continuing trastuzumab beyond progression is acceptable with limited efficacy when other anti-HER2 treatment is unavailable. This single-arm, phase II study (SYSUCC-005) aimed to explore the efficacy of switching mode for HER2-positive refractory metastatic breast cancer.Methods: Patients with HER2-positive metastatic breast cancer rapidly progressing during pre-trastuzumab from six hospitals in China were designed to switch to lapatinib 1,250 mg orally once per day continuously plus capecitabine (1,000 mg/m2 orally twice per day on days 1-14) or vinorelbine (25 mg/m2 intravenously once per day on days 1 and 8) of each 21-day cycle. The primary endpoint was progression-free survival (PFS).Results: Between January 5, 2015 and May 31, 2020, 159 patients were eligible in this study. The median follow-up was 33.1 months, a median PFS of 8.5 months was achieved. Brain metastases (hazard ratio [HR] = 1.582, 95% confidence interval [CI] 1.019- 2.453, P = 0.041) and ≥ 2 metastatic sites (HR = 1.679, 95% CI 1.151-2.450, P = 0.007) were independent prognostic factors for PFS. The most common grade ≥ 3 adverse events were diarrhea (3.8%) and hand-foot syndrome (9.4%).Conclusion: The switching mode showed predominant efficacy, which might be a prior therapeutic option over continuing mode in subsequent anti-HER2 therapy for patients with HER2-positive refractory metastatic breast cancer.Trial Registration: This trial was registered on ClinicalTrials.gov ( NCT02362958 ) on 13/02/2015. [ABSTRACT FROM AUTHOR]

Key message: The powdery mildew resistance gene Pm58 was traced to a 141.3-kb interval with the co-segregating marker Xkasp68500 in wheat breeding. Pm58 is a powdery mildew resistance gene identified in Aegilops tauschii accession TA1662 and effective in a common wheat background. To finely map Pm58, an F2 population of 676 plants derived from the cross T093 × TA1662 was used for recombinant screening. We obtained 13 recombinants that occurred between the flanking markers Xhnu670 and Xhnu186. Genotyping and phenotyping these recombinant F2:3 families delimited Pm58 to a 0.22-cM interval (Xsts20220–Xkasp61553) on chromosome arm 2DS. The region carrying the Pm58 locus was approximately 141.3-kb, which contained eight annotated genes according to the reference genome sequence of Ae. tauschii AL8/78. Haplotype analysis of 178 Ae. tauschii accessions using the candidate gene-specific markers identified a disease resistance gene AET2Gv20068500 as a candidate for Pm58. Comparative mapping of the Pm58-containing interval revealed two presence/absence variations (PAVs) between AL8/78 and common wheat Chinese Spring. PAV-1 resides in the 3′-end of AET2Gv20068500. The majority of 158 common wheat cultivars (84.8%) displayed the absence of a 14.1-kb fragment in the PAV-1 region, which was confirmed by aligning the targeted genome sequences of the other sequenced Ae. tauschii accessions and common wheat cultivars. A co-segregating marker Xkasp68500 developed from AET2Gv20068500 can distinguish TA1662 from all randomly selected common wheat cultivars and will be instrumental for tracking Pm58 in breeding programs. [ABSTRACT FROM AUTHOR]

Abstract: A polyaniline–ionic liquid (i.e. 1-butyl-3-methylimidazolium tetrafluoroborate, [C4mim][BF4]) composite film coated platinum wire (PANI–IL/Pt) was prepared by electrochemical method for the first time. Scanning electron microscopy image showed that the PANI–IL composite film was even and porous. When the PANI–IL/Pt was used as a fiber for the headspace solid-phase microextraction (HS-SPME) of some benzene derivatives (i.e. 1,3-dimethylbenzene, 1,2-dimethylbenzene, 1,4-dichlorobenzene, 1,2-dichlorobenzene, 1,3,5-trimethylbenzene and 1,2,4-trimethylbenzene), followed by gas chromatographic analysis, it presented excellent performance, which was much better than that of PANI/Pt and commercial polydimethylsiloxane fiber. Hence the fiber was coupled with gas chromatography for the determination of these benzene derivatives. It was found that under the optimized conditions the linear ranges were 0.04–400μgL−1 with correlation coefficients above 0.99, the detection limits were 9.3–48.1ngL−1 (S/N=3), the relative standard deviations (RSDs) were smaller than 5.1% for five successive measurements with single fiber, and the RSDs for fiber-to-fiber were 5.0–11.1% (n =3) for different benzene derivatives. The proposed method was successfully applied to the extraction and determination of benzene derivatives in waste water and tap water, and the recoveries were 87.1–108.1% for different analytes. Therefore, the PANI–IL/Pt is a promising SPME fiber. [ABSTRACT FROM AUTHOR]

HRP@ZIF–8 nanocomposite was prepared by in situ encapsulation of horseradish peroxidase (HRP) in the frame of zeolitic imidazolate framework–8 (ZIF–8) with a simple one-pot method. The HRP@ZIF–8 nanocomposite displays outstanding thermal stability and efficiently catalyzes the chemiluminescence (CL) reaction of luminol with hydrogen peroxide (H2O2) under near-neutral pH condition (pH 7–8). This CL system has a good response to H2O2 with a linear range of 0.1–100.0 μmol L−1. The limit of detection (LOD) is 0.06 μmol L−1 H2O2. By marriage with cholesterol oxidase, cholesterol is determined with a linear range from 0.1 to 100.0 μmol L−1 and a LOD of 0.04 μmol L−1. The relative standard deviations (RSD) are 1.7% and 2.5%, respectively, in 11 repeated measurements of 50.0 μmol L−1 solutions of H2O2 and cholesterol, indicating excellent precision of the method. The method shows good selectivity and has been applied to the determination of total cholesterol in real serum samples. No significant difference has been observed between the results obtained by this method and the cholesterol oxidase–peroxidase coupling method. [ABSTRACT FROM AUTHOR]

Using carbene transfer reactions, four new rhodium complexes of N-heterocyclic carbenes, e.g. RHC, are prepared. [ABSTRACT FROM AUTHOR]