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Uncontrollable bleeding and infection are two of the most common causes of trauma-related death. Yet, developing safe materials with high hemostatic and antibacterial effectiveness remains a challenge. Keratin-based biomaterials have been reported to exhibit the functions of enhancing platelet binding and activating and facilitating fibrinogen polymerization. In this study, we designed a hemostatic material with good biodegradability, biocompatibility, hemostatic ability, and antibacterial function to solve the shortcomings of common hemostatic materials. Methylene blue-loaded keratin/alginate composite scaffolds were prepared by the freeze-gelation method. The composite scaffolds exhibited over 1600% liquid absorption, well-interconnected pores, good biocompatibility, and biodegradability. We find that the keratin/alginate composite scaffolds' synergistic action may significantly reduce hemostasis time. To prevent infection, the drug-loaded scaffolds generated high burst release by absorbing wound exudate in the early stages of wound healing. The results obtained by the antimicrobial photoinactivation assay

Mitochondria-targeted fluorescent organic nanoparticles (TYDLs) with a low detection limit (75 nM) were reported for the ratiometric detection of SO2/HSO3−in vitro and in vivo.

Two kinds of AIE-active fluorescent organic nanoparticles were designed and constructed as anti-counterfeiting photoresponsive materials. One is fluorescent organic nanoparticles (TPELs) based on a self-assembly strategy, which were self-assembled from novel amphiphilic tetraphenylethylene (TPE) molecules decorated with a lactose moiety and different photoresponsive tags. The other is polymeric fluorescent organic nanoparticles (F-TPEs) derived from the nanoprecipitation strategy, which utilized pluronic copolymer F127 to encapsulate hydrophobic TPEs without lactosyl modifications. Upon UV light irradiation, these AIE-active materials exhibit different photooxidation behaviors in an aqueous solution to give cyan, orange and green fluorescence emissions, and they were successfully used as an anti-counterfeiting fluorescent hydrogel and ink.

A dilactosyl-dicyanovinyl-functionalized tetraphenylethene (TPELC) was designed, synthesized and used for ratiometric sensing of cyanide. TPELC was comprised of three moieties (tetraphenylethylene, dicyanovinyl group and lactose unit) in one molecule, making TPELC water-soluble and aggregation-induced emission (AIE)-active and selectively reactive to cyanide. Compared with other reported fluorescent probes containing dicyanovinyl group, TPELC is the first AIE luminogen to be assembled as fluorescent organic nanoparticles (FONs) for sensing of cyanide in water without the use of surfactant or the help of organic solvents based on the nucleophilic addition reaction. The detection mechanism was verified by liquid chromatograph mass spectrometry experiments and by protonation of cyanide to reduce the nucleophilicity of cyanide. In addition, TPELC was used for detection of the cyanide content of food samples and test strips were developed to simplify the detection procedure.

Hypochlorous acid (HOCl) plays a crucial role in many physiological processes and is widely used as bleach, deodorant and fungicide. In this work, we designed an amphiphilic hydrazone fluorescent molecule THG-1 containing hydrophilic sugar units and hydrophobic tetraphenylethylene unit for ratiometric detection of HOCl with high sensitivity and excellent selectivity based on HOCl-triggered hydrolyzation reaction and aggregation-induced emission (AIE) effect. The detection mechanism was verified by liquid chromatograph mass spectrometry experiments and scanning electron microscope (SEM) tests. Contrast experiments revealed that the numbers of lactose unit and hydrazone linker were essential for assembly of THG-1 and detection of HOCl. In addition, THG-1 was successfully used for imaging of exogenous and endogenous HOCl in living cells.

Catechol estrogens (CEs) are known to be toxic metabolites and the initiators of the oncogenesis of breast cancers via forming covalent adducts with DNAs. CEs shall also react with proteins, but their cellular protein targets remain unexplored. Here, we reported the identification of protein targets of CEs in the soluble cytosol of estrogen-sensitive breast cancer cells by multiple comparative proteomics using liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with an improved click chemistry-based workflow. Multiple comparative proteomics composed of an experimental pair (probe versus solvent) and two control pairs (solvent versus solvent and probe versus solvent without enrichment) were studied using stable isotope dimethyl labeling. The use of 4-hydroxyethynylestradiol (4OHEE2) probe with an amide-free linker coupled with on-bead digestion and redigestion of the proteins cleaved from the beads was shown to greatly improve the recovery and identification of CE-adducted peptides. A total of 310 protein targets and 40 adduction sites were repeatedly (n ≥ 2) identified with D/H (probe/solvent) ratio >4 versus only one identified with D/H >4 from the two control pairs, suggesting that our workflow imposes only a very low background. Meanwhile, multiple comparative D/H ratios revealed that CEs may downregulate many target proteins involved in the metabolism or detoxification, suggesting a negative correlation between CE-induced adduction and expression of proteins acting on the alleviation of stress-induced cellular damages. The reported method and data will provide opportunities to study the progression of estrogen metabolism-derived diseases and biomarkers.

The lack of structural information impeded the access of efficient luminescence for the exciplex type thermally activated delayed fluorescence (TADF). We report here the pump-probe Step-Scan Fourier transform infrared spectra of exciplex composed of a carbazole-based electron donor (CN-Cz2) and 1,3,5-triazine-based electron acceptor (PO-T2T) codeposited as the solid film that gives intermolecular charge transfer (CT), TADF, and record-high exciplex type cyan organic light emitting diodes (external quantum efficiency: 16%). The transient infrared spectral assignment to the CT state is unambiguous due to its distinction from the local excited state of either the donor or the acceptor chromophore. Importantly, a broad absorption band centered at ~2060 cm−1 was observed and assigned to a polaron-pair absorption. Time-resolved kinetics lead us to conclude that CT excited states relax to a ground-state intermediate with a time constant of ~3 µs, followed by a structural relaxation to the original CN-Cz2:PO-T2T configuration within ~14 µs., The development of exciplex-type hosts for thermally activated delayed fluorescence organic light-emitting diodes is hindered by a lack of structural information for these donor:acceptor blends. Here, the authors report the pump-probe Step-Scan Fourier transform IR spectra for a D:A exciplex host.

Two water-soluble carbohydrate-coated AIE-activate fluorescent organic nanoparticles TPE3G and TPE4G were designed and synthesized for the detection of heparin. Different from the reported strategy, we not only utilized the general detection mechanism of electrostatic interactions, but also introduced the concept of carbohydrate-carbohydrate interactions (CCIs) to enrich the detection mechanism of heparin. TPE3G can serve as an efficient "turn-on" probe with higher selectivity towards heparin than TPE4G. TEM studies revealed that the micro-aggregated TPE3G was encapsulated with the heparin chain to form a complex self-assemblied composite and emits strong fluorescence. It is believed that the results illustrated in this study provide a novel strategy based on CCls to design water-soluble and more efficient bio-probes for various biological and clinical applications.

Herein, four new cadmium metal–organic frameworks (Cd–MOFs), [Cd(bib)(bdc)]∞ (1), [Cd(bbib)(bdc)(H2O)]∞ (2), [Cd(bibp)(bdc)]∞ (3), and [Cd2(bbibp)2(bdc)2(H2O)]∞ (4), have been constructed from the reaction of Cd(NO3)2⋅4 H2O with 1,4-benzenedicarboxylate (H2bdc) and structure-related bis(imidazole) ligands (1,4-bis(imidazol-1-yl)benzene (bib), 1,4-bis(benzoimidazol-1-yl)benzene (bbib), 4,4′-bis(imidazol-1-yl)biphenyl (bibp), and 4,4′-bis(benzoimidazol-1-yl)biphenyl (bbibp)) under solvothermal conditions. Cd–MOF 1 shows a 2D (4,4) lattice with parallel interpenetration, whereas 2 displays an interesting 3D interpenetrating dia network, 3 exhibits an unusual 3D interpenetrating dmp network, and 4 presents a 3D self-catenated pillar-layered framework with a Schafli symbol of [43⋅63]2⋅[46⋅616⋅86]. The structural diversity indicates that the backbone of the bis(imidazole) ligand (including the terminal group and spacer) plays a crucial role in the assembly of mixed-ligand frameworks. By using the pore-forming effect of cadmium vapor, for the first time we have utilized these Cd–MOFs as precursors to further prepare porous carbon materials (PCs) in a calcination–thermolysis procedure. These PCs show different porous features that correspond to the topological structures of Cd–MOFs. Significantly, it was found that the specific surface area and capacitance of PCs are tuned by the Cd/C ratio of the MOF. Furthermore, the as-synthesized PCs were processed with KOH to obtain activated porous carbon materials (APCs) with higher specific surface area and porosity, which greatly promoted the energy-storage capacity. After full characterization, we found that APC-bib displays the largest specific surface area (1290 m2 g−1) and total pore volume (1.37 cm3 g−1) of this series of carbon materials. Consequently, APC-bib demonstrates the highest specific capacitance of 164 F g−1 at a current density of 0.5 A g−1, and also excellent retention of capacitance (≈89.4 % after 5000 cycles at 1 A g−1). Therefore, APC-bib has great potential as the electrode material in a supercapacitor.

Catechol estrogens (CEs) are metabolic electrophiles that actively undergo covalent interaction with cellular proteins, influencing molecular function. There is no feasible method to identify their binders in a living system. Herein, we developed a click chemistry-based approach using ethinylestradiol (EE2) as the precursor probe coupled with quantitative proteomics to identify protein targets of CEs and classify their binding strengths. Using in situ metabolic conversion and click reaction in liver microsomes, CEs-protein complex was captured by the probe, digested by trypsin, stable isotope labeled via reductive amination, and analyzed by liquid chromatography-mass spectrometry (LC-MS). A total of 334 liver proteins were repeatedly identified ( n ≥ 2); 274 identified proteins were classified as strong binders based on precursor mass mapping. The binding strength was further scaled by D/H ratio (activity probe/solvent): 259 strong binders had D/H5.25; 46 weak binders had 5.25D/H1; 5 nonspecific binders (keratins) had D/H1. These results were confirmed using spiked covalent control (strong binder) and noncovalent control (weak binder), as well as in vitro testing of cytochrome c (D/H = 5.9), which showed covalent conjugation with CEs. Many identified strong binders, such as glutathione transferase, catechol-O-methyl transferase, superoxide dismutase, catalase, glutathione peroxidase, and cytochrome c, are involved in cellular redox processes or detoxification activities. CE conjugation was shown to suppress the superoxide oxidase activity of cytochrome c, suggesting that CEs modification may alter the redox action of cellular proteins. Due to structural similarity and inert alkyne group, EE2 probe is very likely to capture protein targets of CEs in general. Thus, this strategy can be adopted to explore the biological impact of CEs modification in living systems.

A K2S2O8/I2 promoted C–S coupling reaction of β-diketones with disulfides has been described. The resulting α-thio-β-diketone compounds were obtained in good to excellent yields. Both diaryl and dialkyl disulfides coupled well with a variety of β-diketones under transition metal-free and solvent-free conditions.

The high thermal stability of the Lewis acidic ZnCl2-1-ethyl-3-methylimidazolium chloride ionic liquid enables the in situ fabrication of hierarchical nanostructured Pd–Au bimetallic surfaces via electrochemical alloying/dealloying of (PdAu)Zn on PdAu substrate in the ionic liquid. Nanostructured PdAu samples that consist of patterned cracks and ligaments are fabricated by using potential cycling method and constant-potential electrolysis method, respectively. The effects of working temperature and amounts of the deposited Zn on the morphology of the dealloyed (PdAu)Zn nanostructure are examined. The formation of the hierarchical nanostructure is a compromise between high-surface-diffusive Au and low-surface-diffusive Pd. Whereas Au in the alloy promotes the nanostructure formation, Pd in the PdAu nanostructure protects this material from coarsening. Compared with the plain PdAu, the nanostructured PdAu surface prepared at 150 °C exhibits a significantly higher active surface area and a high capability for the electro-oxidation of glucose.

Titanium dioxide (TiO2) nanorods with anatase phase were successfully fabricated by electrospinning and followed calcination. The TiO2 nanorods were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and UV-visible spectroscopy. The diameter of the TiO2 nanorods was about 60–150 nm and the length was 200 nm–2 μm. Electrical properties under bending were investigated by fixing the device to a curved surface with different curvatures, and the device showed a fast and stable resistance response to curvature changing. Photoelectric properties were studied by irradiation with different light intensities. The device exhibited a short response time (∼10 s) and a high sensitivity (∼103) which increased with the light intensity increasing. These results indicate that electrospun anatase TiO2 nanorods have potential applications in flexible photodetectors and solar cells.

Sulfur-containing molecules such as thioethers are commonly found in chemical biology, organic synthesis, and materials chemistry. While many reliable methods have been developed for preparing these compounds, harsh reaction conditions are usually required in the traditional methods. The transition metals have been applied in this field, and the palladium-catalyzed coupling of thiols with aryl halides and pseudo halides is one of the most important methods in the synthesis of thioethers. Other metals have also been used for the same purpose. Here, we summarize recent efforts in metal-catalyzed C-S bond cross-coupling reactions, focusing especially on the coupling of thiols with aryl- and vinyl halides based on different metals.

A DTBP-promoted, operationally simple, metal-free and solvent-free formation of C–Se and C–S bonds through sp3C–H functionalization of methyl arenes with diselenides and disulfides is described.

A systematic investigation of elutriation of particles is reported in the cold model of bubbling fluidized bed (BFB) and vortexing fluidized bed (VFB) of 0.19 m diameter and 4.0 m height. Glass beads were used as the fluidized material. The diameter of the coarse particles was 545 μm, the diameter of the fine particles used for the elutriation test ranged from 49 to 194 μm. The results indicate that the specific elutriation rate constant (K∞*) is a function of the initial concentration of elutriated fine particles. The minimum value of K∞* is obtained when the initial concentration of elutriated fine particles is reached 16 wt% in a BFB system. Based on the experimental data obtained from the BFB, a correlation is presented to estimate the K∞*. The K∞* is found to be a function of the particle terminal velocity, gas density, and modified Froude number (Fr*). For a wide particle size distribution (PSD) system, a new parameter, called particle size distribution factor, γ, is introduced to describe the specific elutriation rate constant of wide PSD elutriated fine particles. A method to estimate the specific elutriation rate constant of a multi-component system by using the specific elutriation rate constant of each component obtained from a binary particle mixture system is also presented in this study.