Fast and Sensitive Detection of CO by Bi-MOF-Derived Porous In2O3/Fe2O3 Core-Shell Nanotubes.

In2O3 is an optimal material for sensitive detection of carbon monoxide (CO) gas due to its low resistivity and high catalytic activity. Yet, the gas response dynamics between the CO gas molecules and the surface of In2O3 is limited by its solid structure, resulting in a weak gas response value and sluggish electron transport. Herein, we report a strategy to synthesize porous In2O3/Fe2O3 core-shell nanotubes derived from In/Fe bimetallic organic frameworks. The fabricated porous In2O3/Fe2O3-4 core-shell nanotubes present outstanding gas sensitivities, including a response value 3.8 times (33.7 to 200 ppm CO at 260 °C) higher than that of monometallic-derived In2O3 (8.7), ultrashort response and recovery times (23/76 s) to 200 ppm CO, low detection limit (1 ppm), promising selectivity, and long-term stability. The enhanced sensing mechanisms are clarified by the combination of experiment and first-principles calculations, showing that the synergetic strategy of higher adsorption energy, increased electrical conductivity, higher electron transfer numbers, and larger specific surface area of porous core-shell structures promotes the surface activity and charge transfer efficiency. The present work paves a way to tune gas-sensing materials with special morphologies for the development of high-performance CO sensors.

Immune infiltration associated C1q acts as a novel prognostic biomarker of cutaneous melanoma.

C1q (complement C1q A chain, complement C1q B chain, and complement C1q C chain) is a recognized component of the classical complement pathway that influences the prognosis of various cancers. However, the effects of C1q on cutaneous melanoma (SKCM) outcomes and immune infiltration remain unknown. Gene expression profiling interactive analysis 2 and the human protein atlas were used to evaluate differential expression of C1q mRNA and protein. The relationship between C1q expression and clinicopathological features was also examined. The genetic alterations of C1q and their impact on survival were analyzed using the cbioportal database. The Kaplan-Meier approach was used to assess the significance of C1q in individuals with SKCM. The cluster profiler R package and the cancer single-cell state atlas database were used to investigate the function and mechanism of C1q in SKCM. The relationship between C1q and immune cell infiltration was estimated using single-sample gene set enrichment analysis. C1q expression was increased, and predicted a favorable prognosis. High C1q expression correlated with clinicopathological T stage, pathological stage, overall survival, and disease specific survival events. Moreover, C1q genetic alterations range from 2.7% to 4%, with no impact on prognosis. According to the enrichment analysis, C1q and immune-related pathways were closely connected. The link between complement C1q B chain and the functional state of inflammation was determined using the cancer single-cell state atlas database. In particular, C1q expression was significantly associated with infiltration of most immune cells and checkpoints PDCD1, CD274, and HAVCR2. The results of this study suggest that C1q is associated with prognosis and immune cell infiltration, supporting its value as a diagnostic and prognostic biomarker.

Visible light-induced N-radical 5-exo/6-endo cyclization of alkenyl amides: facile access to isoindolinones/isoquinolinones.

An efficient N-centered radical intramolecular cyclization reaction of alkenyl amides induced by visible light was described. In this process, an alkenyl amide underwent 5-exo/6-endo cyclization to selectively yield two critical alkaloid structures, namely isoindolinones and isoquinolinones.

A turn-on luminescence probe for highly selective detection of an anthrax biomarker.

Highly selective detection of Bacillus anthrax spores has attracted worldwide attention because Bacillus anthrax spores not only are harmful to the health of human beings and animals, but also can be used as biological warfare agents. Here, we report a simple platform by mixing EuCl3 ·6H2 O and sodium polyacrylate in aqueous solution and further investigate its luminescence response towards Bacillus anthrax biomarker dipicolinic acid (DPA) as a turn-on luminescence probe. Importantly, our probe has good sensitivity, lower detection limit, excellent selectivity as well as great anti-interference ability due to the great luminescence enhancement of Eu3+ . Moreover, a test paper is constructed to realize the purpose of portable detection. These results indicate that our probe is an excellent candidate for sensing DPA.

A highly selective lanthanide-containing probe for ratiometric luminescence detection of an anthrax biomarker.

Since anthrax spores are highly lethal to human beings and animals, and also potential biological warfare agents, it is highly desirable to develop simple, robust and easy-device sensors that are rapid and sensitive, and can selectively detect the Bacillus anthrax biomarker dipicolinic acid (DPA) quantitatively. Herein, we report a ratiometric luminescent "turn-on" sensor via mixing Eu3+ ions, sodium polyacrylate and internal luminescence reference in water, which can identify the Bacillus anthrax biomarker dipicolinic acid (DPA) quantitatively with outstanding selectivity over aromatic ligands and amino acids, even including all of the 5 DPA isomers.

Construction of anisotropic fluorescent nanofibers assisted by electro-spinning and its optical sensing applications.

Fixing the gap between "nano-scaled" pieces and "product-scale" materials, devices or machines is an ineluctable challenge that people have to tackle. Herein, we show that combining self-assembly and electrospinning processes results in the fabrication of anisotropic fluorescent nanofibers (PDI@PVDF) in which the well-defined rod-like perylene bisimide derivative assemblies are embedded in a highly oriented way along the axis of the poly(vinylidene fluoride) (PVDF) fiber. Compared to fragile individual PDI assemblies, the electrospinning anisotropic fluorescent PDI@PVDF nanofibers not only maintain high sensitivity for aniline vapour but also exhibit an unexpected short response time for both quenching and recovering. The results demonstrate that electrospinning assistance is a versatile and effective strategy to maintain the anisotropy of fluorescent nanomaterials, building a bridge between self-assembled nano-rods and practical materials.

2,2'-Biphen[n]arenes (n = 4-8): one-step, high-yield synthesis, and host-guest properties.

A new family of biphen[n]arenes (n = 4-8) with 2,2'-disubstituents (2,2'-BPns) has been designed and synthesized. The host-guest properties of the 2,2'-BPns have been examined; they exhibit strong binding affinities towards selected organic cationic guests.

[Synthesis of naphthalimide derivatives and its recognition of Fe3+].

A novel naphthalimide derivatives N-hexyl-4-benzylamino-naphthalimide(HBN) was synthesized from 4-bromo-1, 8-naphthalic anhydride, and the structure was characterized by NMR and MS. Spectral properties of HBN for recognition of Fe3+ were investigated by fluorescence spectrum. In a certain range of Fe3+ from 4 x 10(-7) to 1 x 10(-2) mol x L(-1), the fluorescence intensity of HBN significantly reduced with increasing concentration of Fe3+ in ethanol/water (1:1, volume ratio). The equation of linear regression was F0/F=623.253 2c(Fe3+) + 0.9642 (R2 = 0.9963). Moreover, no obvious interference with the detection of the Fe3+ ion was observed in the presence of the common metal ions such as Ca2+, Na+, CU2+, Zn2+, Pb2+, Co2+, Ni2+, Mn2+ and Fe2+, which indicated that HBN displayed excellent selectivity and high sensitivity for the detection of Fe3+.

[Analysis of H2S/PH3/NH3/AsH3/Cl2 by Full-Spectral Flame Photometric Detector].

Flame photometric analysis technology has been proven to be a rapid and sensitive method for sulfur and phosphorus detection. It has been widely used in environmental inspections, pesticide detection, industrial and agricultural production. By improving the design of the traditional flame photometric detector, using grating and CCD sensor array as a photoelectric conversion device, the types of compounds that can be detected were expanded. Instead of a single point of characteristic spectral lines, full spectral information has been used for qualitative and quantitative analysis of H2S, PH3, NH3, AsH3 and Cl2. Combined with chemometric method, flame photometric analysis technology is expected to become an alternative fast, real-time on-site detection technology to simultaneously detect multiple toxic and harmful gases.

Controlled photophysical behaviors between dibenzo-24-crown-8 bearing terpyridine moiety and fullerene-containing ammonium salt.

A novel [2]pseudorotaxane was successfully constructed by the complexation of dibenzo[24]-crown-8 (DB24C8) derivative bearing terpyridine moiety (1) with lanthanide ion (Tb(3+)) and fullerene-containing ammonium salt (2), exhibiting the controlled photophysical behaviors as a reversible luminescent lanthanide switch in the presence of K(+) or 18-crown-6 (18C6).

A heterowheel [3]pseudorotaxane by integrating ß-cyclodextrin and cucurbit[8]uril inclusion complexes.

A heterowheel [3]pseudorotaxane was prepared by integrating two binary inclusion complexes of ß-cyclodextrin-hydroxynaphthalene (ß-CD·3) with a cucurbit[8]uril-viologen derivative (CB[8]·2), in which simultaneous molecular recognition of the adamantine moiety in 2 by ß-CD and the charge-transfer interaction of 3 with the viologen nucleus of 2 in the cavity of CB[8] are two crucial factors for the formation of the quaternary complex.

pH-Controlled intramolecular charge-transfer behavior in bistable [3]rotaxane.

Two [3]rotaxanes with an electron-rich pyrene moiety at the wheel and an electron-deficient naphthalenediimide (NDI) unit in the middle of the axle were prepared through "click chemistry", in which the intramolecular charge-transfer (ICT) process occurred between the pyrene moiety and the NDI unit, and the addition of acid and/or base can adjust the intensity of ICT.