We report the development of a red-emitting fluorescence probe (XDS) for hydrogen sulfide (H2S) detection in biosystems, real-world food samples, and application of this probe for monitoring of H2S production during food spoilage. The XDS probe is developed by coupling of coumarin derivative to rhodanic-CN through a H2S responsive CC bond. Remarkable fluorescence quenching of XDS is observed as a result of the response to H2S. Semi-quantitative detection of H2S in three real-world water and two beer samples and monitoring of H2S production during food spoilage in real-time by "naked-eye" and smartphone colorimetric analysis are then achieved using XDS as the probe. Moreover, XDS is low toxicity, allowing it being used for visualizing endogenous and exogenous H2S in vivo in a mouse model. It is expected that the successful development of XDS could provide an effective tool for investigating the roles of H2S in biomedical system and for future food safety evaluation.
Objective To investigate antiviral and immunoregulation effects of indole-2,3-dine(ISA).Methods The BHK-21 cell model infected with Sendai virus was established and the antiviral effect of ISA was observed by cytopathic effect(CPE) method;its effect on immunological function was observed by hemagglutination inhibition test using Sendai virus infected mice model.Results ISA showed cytotoxicity when the concentration was above(0.313)mg·mL~(-1),while ISA showed a dose-dependent antiviral effect without cytotoxicity when the concentration was among 0.156~0.039mg·mL~(-1).ISA at higher dose(2%) could accelerate the production of hemagglutination inhibition antibody in hemagglutination test(P(0.01)).Conclusion ISA has antiviral effects and can enhance immunological function.
In this study, by designing high-speed transimpedance amplification circuit and developing photon counting program in the Labview platform, we investigate the variation curve of the area integral (essentially the charge) of the output waveform of Silicon photomultiplier (SiPM) versus the incident light flux (the number of photons irradiated to the surface of SiPM per unit of time). The maximum photon counting rate of 1.56 Gcps was obtained at 470 nm at room temperature. When the light intensity increases to a certain extent, due to the saturation of the SiPM, the photon counting rate did not increase with the increase of the light intensity anymore. In addition, by recording the incident photon number of the calibrated photodiode, we also plot the photon detection effieciency (PDE) curve versus the incident light wavelength under different light intensities. The PDE curves were in accordance with the ones in the datasheet of the SiPM when the light intensity is much smaller than the saturation light intensity for the SiPM.
Uranium, regarded as an important element in nuclear fission energy schemes, is harmful to public health owing to its high toxicity and radioactivity. Herein, a novel fluorescent probe (SC4A@Tb3+) was developed using a one-step liquid-phase method with 4-sulfocalix [4] arene (SC4A) and rare earth–metal ions (Tb3+) as precursors to realize the accurate monitoring of uranyl ion (UO22+) detection. Based on the dynamic quenching mechanism, the SC4A@Tb3+ fluorescence quenching sensor for UO22+ detection was in the linear range of 0.04–0.36 µM, with a detection limit of 40 nM, and successfully quantified UO22+ in water and human serum samples. These results suggest that SC4A@Tb3+ is a potential sensing material for UO22+ detection.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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