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This work focused on design, synthesis and application of an AIE and FRET-based BODIPY pH sensor bearing large Stoke shift. The cyano-diphenylethylene- conjugated BODIPY derivative 4 was prepared by condensating 4-hydroxybenzene acetonitrile with 4-(diethoxymethyl)benzaldehyde and then following the typical procedure of synthesizing BODIPY derivative. Compound 4 exhibited strong fluorescence in all kinds of THF/H2O solutions due to the AIE and FRET effect. The Stoke shift of compound 4 was as large as 138 nm based on the excitation of cyano-diphenylethylene moiety and the emission of BODIPY moiety. Compound 4 showed good fluorescent response to the change of pH with the pKa value at 9.79. The mechanism of compound 4 as pH probe was confirmed by 1H NMR spectra and theoretical calculation. Compound 4 was successfully used to CO32− detection among 13 kinds of common anions both in solution and by tested strips. The experiments of living cell imaging suggested that compound 4 possessed superior bioimaging performance and presented sensitive change to pH values between 9 and 10 in living cells.

Three novel triphenylene tetramers with triazole bridges, rigid aromatic Schiff-bases and hydrogen-bonding spacers were designed and synthesized in yield of 73–78%. Their structures were confirmed by IR, NMR and MS. Their mesomorphic properties were studied by polarizing optical microscopy, differential scanning calorimetry and X-ray diffraction. These novel triphenylene tetramers possessed the hexagonal columnar mesophase and exhibited excellent mesomorphic properties with melting points at 30–60 °C, which was first observed near room temperature for triphenylene tetramers. This study suggested that the mesomorphic properties of triphenylene oligomers could be tuned conveniently by the structures of spacers.

Divalent palladium-induced homocoupling of terminal zinc hydrides to zinc–zinc bonded complexes was achieved herein. Reactions of zinc hydrides [LZnH] (L = CH3C(2,6-iPr2C6H3N)CHC(CH3)(N(CH2)nCH2PPh...

Although all kinds of sensors with unique detecting ability for one guest were reported, the fluorescence sensor with multiple detecting abilities was seldom presented. This work designed and synthesized a novel AIE fluorescence probe bearing double detecting for ATP based on Cu

Knowledge of the molecular-level structure of the Li

Surgical excision is the main choice for tongue cancer treatment. However, the physiological functions of oral and maxillofacial regions might be severely impaired and high risk of tongue tumor recurrence cannot be avoided. It is thus becoming urgently important to develop alternative strategies for tongue cancer therapy. In this regard, a new class of near-infrared (NIR) light-responsive and peritumoral injectable hydrogel is fabricated with extraordinary photothermal therapy (PTT) for in situ tongue tumors. The as-prepared soft material exhibits good biocompatibility and ultra-strong photothermal effect due to the formed network by negatively charged proteins, chitosan molecules, and Ag3 AuS2 nanoparticles (NPs). In a well-constructed in situ tongue tumor model, tumors can be efficiently eradicated by one-time PTT treatment. Importantly, there are no side effects on surrounding normal tissues and potential tumor recurrence is inhibited. In stark contrast to traditional surgical excision, such biomaterials hold great potential for clinical treatment of oral cancers.

A novel photothermal hydrogel is fabricated, which can transform into a mechanically strong network by in situ gelation with Ca2+ in tissues. With the properties of good biocompatibility, long residential time, outstanding photothermal conversion efficiency, and high toughness, the hydrogel can be used as an ideal platform to realize a significant tumor photothermal therapy effect and bone defects repair simultaneously.

Previously reported fluorescent sensors for Th4+ experienced emission quenching or generated false positive signal upon aggregate formation in aqueous media. Herein, a simple and novel thorium sensor (CDB-BA) based on cyanodistyrene structure was designed and synthesized, which integrated the highly emitting characteristic of AIE effect and off-on response of PET modulation for the first time to construct the “turn-on” fluorescent probe for Th4+. Besides excellent selectivity, CDB-BA exhibited remarkable fluorescent enhancement which was linearly related to the concentration of Th4+ in the range of 0.25–8 μM. The detection limit was attained 0.074 μM, which was lower than that of most previously reported sensors. The mechanism of tris-chelate complex of CDB-BA with Th4+ was confirmed by mass spectra, IR spectra and DFT calculation. The excellent Th4+ sensing ability of CDB-BA was successfully applied to detecting Th4+ on TLC plates, in real water samples and living-cell imaging. This work suggested that the combination of AIE and PET photophysical mechanism could offer the merits of minimized background and enhanced signal fidelity to develop novel “turn-on” fluorescent probe in complicated aqueous environment and biological research.

The early diagnosis of recurrence and metastasis is critically important for decreasing the morbidity and mortality associated with oral cancers. Although liquid biopsy methods hold great promise that provide a successive "time-slice" profile of primary and metastatic oral cancer, the development of non-invasive, rapid, simple, and cost-effective liquid biopsy techniques remains challenging. In this study, an ultrasensitive and selective electrochemical liquid biopsy is developed for oral cancer screening based on tracking trace amounts of cancer biomarker by functionalized asymmetric nano-channels. Detection via antigen-antibody reactions is assayed by evaluating changes in ionic current. Upon the recognition of cancer biomarker antigens in bio-fluids, the inner wall of nano-channel immobilized with the corresponding antibodies undergoes molecular conformation transformation and surface physicochemical changes, which significantly regulate the ion transport through the nano-channel and help achieve sensitivity with a detection limit of 10

Biogenesis and tissue development are based on the heterogenesis of multipotent stem cells. However, the underlying mechanisms of stem cell fate specification are unclear. Chirality is one of the most crucial factors that affects stem cell development and is implicated in asymmetrical cell morphology formation; however, its function in heterogeneous cell fate determination remains elusive. In this study, it is reported that the chirality of a constructed 3D extracellular matrix (ECM) differentiates mesenchymal stem cells to diverse lineages of osteogenic and adipogenic cells by providing primary heterogeneity. Molecular analysis shows that left-handed chirality of the ECM enhances the clustering of the mechanosensor Itgα5, while right-handed chirality decreases this effect. These differential adhesion patterns further activate distinct mechanotransduction events involving the contractile state, focal adhesion kinase/extracellular signal-regulated kinase 1/2 cascades, and yes-associated protein/runt-related transcription factor 2 nuclear translocation, which direct heterogeneous differentiation. Moreover, theoretical modeling demonstrates that diverse chirality mechanosensing is initiated by biphasic modes of fibronectin tethering. The findings of chirality-dependent lineage specification of stem cells provide potential strategies for the biogenesis of organisms and regenerative therapies.

This work report the first AIE-based fluorescence sensor that can simultaneously detect three kinds of IIB elements (Zn2+, Cd2+ and Hg2+) in aqueous media. The thiourea-bridging bis-tetraphenylethylene (Bis-TPE) was synthesized by the condensation reaction of formyltetraphenylethylene and bis-thiosemicarbazide derivative in 82 % yield. Due to the AIE effect in the aqueous medium, the long-wavelength fluorescence was observed at 500–526 nm. It displayed high selective Zn2+-sensing ability with red-to-green fluorescence change, selective Cd2+-sensing ability with red-to-yellow fluorescence change and selective Hg2+-sensing ability with fluorescence enhancement, respectively. Moreover, it could detect simultaneously Zn2+, Cd2+ and Hg2+ in the mixed solution of these three kinds of cations by the fluorescence change with the assistance of Cl− and ATP. The sensing mechanism was confirmed as 1:1 stoichiometric ratio between host and guest. The detection limits were as low as 8.22×10-8 M, 2.36×10-7 M and 3.43×10-8 M for Zn2+, Cd2+ and Hg2+, respectively. These sensing abilities were applied as test strips for detecting Zn2+, Cd2+ and Hg2+, and were used for living cell imaging, implying a high efficient and simple method for analyzing trace IIB elements (Zn2+, Cd2+ and Hg2+) simultaneously in complex environments and living bodies.

This work designed and synthesized the first organic fluorescent sensor for curcumin in aqueous media based on red-to-green fluorescence change of acylhydrazone-bridged bis-tetraphenylethylene (Bis-TPE). Bis-TPE was prepared by condensation of formyltetraphenylethylene with dihydrazide oxalate in 86% yield. It has the large conjugated electron effect with strong red AIE fluorescence in aqueous solution. It displayed high selective sensing ability for curcumin with red-to-green fluorescence change in THF-H2O (5:95). The detection limit was as low as 1.15 × 10−7 M. The sensing mechanism was confirmed as 1:1 stoichiometric ratio based on quadruple hydrogen bonds. Bis-TPE was successfully applied for analyzing curcumin of ginger and living cell imaging, supplying a new detecting strategy for curcumin in real sample and living environment.

Aggregation-induced emission (AIE) molecules eliminate the aggregation-caused quenching (ACQ) phenomenon effectively and exhibit excellent properties of a fluorescent sensor in the aggregated state. In this paper, an allochroic fluorescent sensor based on AIE molecules with a diphenylacrylonitrile structure was prepared in high yield by a simple procedure. This molecule possessed good AIE properties and exhibited a sensitive sensor ability for aliphatic amines with an obvious color change from orange to blue-green. The detailed investigation on the detection of hydrazine suggested that the detection limit for hydrazine was 3.67 × 10-6 M, and the highly sensitive sensor for hydrazine was not influenced by other species. The sensor mechanism was confirmed by using 1H NMR and MS spectra. The sensor for hydrazine was successfully applied in a test paper, exhibiting good practical application potential for detecting hydrazine. The experiment of living cell imaging suggested that this sensor showed superior bioimaging performance and presented sensitive detection for hydrazine with an obvious color change from orange to blue-green.

Aggregation-induced emission (AIE) molecules with strong fluorescence in aggregated states are favourable for preparing the organic fluorescence sensor in aqueous phase. In this work, a red fluorescent sensor 5 based on AIE diphenylacrylonitrile Schiff-base derivative was prepared in yield of 83.7%. Sample 5 exhibited strong AIE property in water with red fluorescence at λex = 620 nm and the Stokes shift was as large as 260 nm. The experiments of sensing series of metallic ions suggested that sample 5 possessed the sequentially detecting abilities for Co2+-Hg2+-Cu2+, which was observed firstly for organic fluorescence sensor. The fluorescence of sample 5 was quenched rapidly in presence of Co2+, then recovered by adding Hg2+ and quenched once more by further adding Cu2+. The detection limits for Co2+, Hg2+ and Cu2+ were 0.0937, 0.0221, and 0.0988 μM, respectively. The sensor mechanism was confirmed by fluorescence titration, 1H NMR and MS spectra, indicating the 2:1 stoichiometric ratios of sample 5 with ions. The sensor for ions was successfully applied in test paper, exhibiting good practical application potential for detecting Co2+-Hg2+-Cu2+ sequentially. Sample 5 showed good bioimaging performance on living cell. The fluorescence of living cells with sample 5 also displayed the similar change of quenching-recovering-quenching by adding Co2+-Hg2+-Cu2+ orderly, implying the good ions-detecting prospect in living body environment.