Publications by authors named "Wen-Jun Shan"

A novel, to the best of our knowledge, type of compact pH fiber sensor combined with a hydrogel based on the whispering gallery mode (WGM) is proposed and integrates a liquid crystal (LC) microdroplet in a capillary in a compact structure as small as 180 µm. In the research, the hydrogel performs both as a supporting frame and a responsive material that causes morphological deformation of the LC microdroplet with pH variation. Moreover, a new phenomenon of pH-induced LC refractive index variation is observed and applied in the pH measurement, so that the acid itself can also lead the LC microdroplet structure transition.

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Ultra-low sample consumption detection has many applications in molecular biology, bioanalytical chemistry, and medical science. In this Letter, a novel, to the best of our knowledge, simple type of ultra-low sample consumption detection method based on a whispering gallery mode is proposed as a means to realize consecutive detection with a liquid crystal (LC) microdroplet for biochemical molecule detection, using deoxyribonucleic acid (DNA) as a model biomarker. The sensor consists of a 105-µm-core multimode fiber fused with a hollow capillary tube, with the LC microdroplet suspended stably in the testing solution.

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A series of novel indanone derivatives was designed, synthesised and evaluated as potential agents for Alzheimer's disease. Among them, compound 6a, with a piperidine group linked to indone by a two-carbon spacer, exhibited the most potent inhibitor activity, with an IC(50) of 0.0018 μM for AChE; the inhibitory activity of this compound was 14-fold more potent than that of donepezil.

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We designed and synthesized a novel class of dual pharmacology bronchodilators targeting both β(2)-adrenoceptor and PDE4 by applying a multivalent approach. The most potent dual pharmacology molecule, compound 29, possessed good inhibitory activity on PDE4B2 (IC(50)=0.278 μM, which was more potent than phthalazinone, IC(50)=0.

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A series of 9-N-substituted berberine derivatives were synthesized and biologically evaluated as antioxidant and inhibitors of acetylcholinesterase (AChE), butyrylcholinesterase and amyloid-β aggregation. Most of these compounds exhibited very good antioxidant activities, inhibitive activities of AChE and amyloid-β aggregation. Among them, compound 8d, (o-methylphenethyl)amino linked at the 9-position of berberine, was found to be a good antioxidant (with 4.

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The nature of liquid structures with their changing behaviors remains an unsolved fundamental problem in many fields of science and technology. It has been widely accepted that liquid structures change gradually with temperature and/or pressure. With x-ray diffraction in the melt In-Sn80, however, we have confirmed that a temperature-dependent discontinuous structural change could occur in some binary liquids, which does not fall into any other up-to-date recognized liquid-liquid changes.

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