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The efficient preparation of long-chain amines via a one-step transfer-hydrogenation/reductive-amination reaction (THRA) of polyenals has been achieved. This strategy, which combines transfer hydrogenation and reductive amination, significantly enhances the synthetic efficiency of amino compounds. Additionally, this protocol offers a practical method for carbon-chain elongation/amination to construct long-chain amino compounds. The reaction system exhibits remarkable versatility in substrate scope using a non-noble ruthenium catalyst with formate and isopropanol as hydrogen sources, making it an appealing method for drug synthesis and molecular modification.

Aiming to decrease the recurrence of tumors and achieve patient satisfaction, the elicitation of immunotherapy and its integrated synergistic employment is a bright new direction in oncotherapy, yet an emergently challenging task. In particular, tumor-associated macrophage (TAM) regulation though light-induced photodynamic and photothermal therapy (PDT and PTT) is regarded as a powerful approach, which focuses on the systemic immune system instead of the tumor itself. Herein, this study reports an acceptor-donor-acceptor (A-D-A) aggregation-induced emission luminogen (AIEgen), named TPA-2CN, which was applied as a photosensitizer (PS) and photothermal agent (PTA). Attributed to its A-D-A structure and AIE properties, TPA-2CN exhibits a high molar absorption coefficient and acts as a perfect template in regulating radiative and nonradiative transitions, which mainly utilize excited energy. The generation of type I reactive oxygen promoted its application in hypoxic tumor sites and the combination of hyperpyrexia forcefully induces macrophages to polarize towards the immune response M1 phenotype. In in vitro and in vivo , the successful reversion and reprogramming of the immune microenvironment was impressively proved. This method optimally concentrated immune therapy, PDT and PTT as one and exhibited excellent synergistic therapeutic effects with good biosafety.

The catalytic asymmetric propargylation of enol(ate) intermediates is a well-established method for the synthesis of α-propargyl-substituted carbonyl compounds. However, the propargylation of homo-enol(ate) or its equivalents for the synthesis of β-propargyl-substituted carbonyl compounds remains underdeveloped. A catalytic enantioselective decarboxylative intramolecular propargylation of cyclopropanols has been developed using a PyBox-complexed copper catalyst. This reaction offers an effective approach to assemble a cyclopentanone skeleton bearing an all-carbon quaternary stereogenic center and an adjacent quaternary gem -dimethyl carbon center, which is the core scaffold of the naturally occurring cuparenoids. Key to the success of this protocol is the use of a new structurally optimized PyBox ligand. This study represents the first example of catalytic asymmetric intramolecular propargylation of cyclopropanols., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Skin wounds significantly impact the global health care system and represent a significant burden on the economy and society due to their complicated dynamic healing processes, wherein a series of immune events are required to coordinate normal and sequential healing phases, involving multiple immunoregulatory cells such as neutrophils, macrophages, keratinocytes, and fibroblasts, since dysfunction of these cells may impede skin wound healing presenting persisting inflammation, impaired vascularization, and excessive collagen deposition. Therefore, cellular target-based immunomodulation is promising to promote wound healing as cells are the smallest unit of life in immune response. Recently, immunomodulatory hydrogels have become an attractive avenue to promote skin wound healing. However, a detailed and comprehensive review of cellular targets and related hydrogel design strategies remains lacking. In this review, the roles of the main immunoregulatory cells participating in skin wound healing are first discussed, and then we highlight the cellular targets and state-of-the-art design strategies for immunomodulatory hydrogels based on immunoregulatory cells that cover defect, infected, diabetic, burn and tumor wounds and related scar healing. Finally, we discuss the barriers that need to be addressed and future prospects to boost the development and prosperity of immunomodulatory hydrogels.

In this work, an eco-friendly, green, efficient approach for oxidative and reductive Heck-Mizoroki (HM) reactions was developed, which offered acceptable yields from first-pass experiments. Mono-arylation was achieved without the use of ligands, directing groups, or prefunctionalized alkenes. Considering mild reaction conditions, good functional group compatibility, and great regioselectivity, the method can find broad applications in novel medicine and material development and discovery processes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

pH-responsive micelles with positive charges are challenged by their significant effect on the cells/proteins and compromise their final fate due to electrostatic interactions. As one of the promising strategies, zwitterion incorporation in micelles has attracted considerable attention and displayed improved protein adsorption and blood circulation performances. However, previous reports in this field have been mostly limited in hemolysis for studying blood behaviour and lack a comprehensive understanding of their interactions with blood components. Herein, we present a prelimilary study on the effect of zwitterionic sulfobetaine incorporation on blood behaviour, phagocytosis, and in vivo biodistribution of pH-responsive micelles with positive charges. Amphiphilic triblock copolymers, namely poly(ε-caprolactone)- b -poly( N , N -diethylaminoethyl methacrylate)-( N -(3-sulfopropyl- N -methacryloxyethy- N , N -diethylammonium betaine)) (PCL-PDEAPS x , x = 2, 6, 10), containing different numbers of sulfobetaine groups were synthesized through four steps to prepare the pH-responsive micelles with positive charges. The effect of the sulfobetaine incorporation displayed different profiles, e.g. , the micelles had no effect on RBC aggregation, thrombin time (TT), and platelet aggregation, while the cytotoxicity, hemolysis, RBC deformability, activated partial thromboplastin time (APTT), prothrombin time (PT), platelet activation, protein (albumin, fibrinogen, plasma) adsorption, phagocytosis, and in vivo biodistribution decreased with the increase in the sulfobetaine number, in which the transition mainly occurred at a sulfobetaine/tertiary amine group ratio of 3/7-1/1 compared to that of the mPEG control. In addition, the micelles displayed a strong inhibitory effect on the intrinsic coagulation pathway, which was associated with a significant decrease in the coagulation factor activity. Based on these findings, the related mechanism is discussed and proposed, which can aid the rational design of pH-responsive micelles for improved therapeutics.

A highly efficient catalyst for Li-O 2 batteries based on Ru and MnFe phosphides nanoparticles entrapped in a MnFe Prussian blue analogue (PBA) substrate (Ru-MnFeP/PBA) was explored. Synergy between homogeneous Ru and MnFe phosphides nanoparticles improved the catalytic activity and alleviated side reactions. The Li-O 2 battery based on Ru-MnFeP/PBA exhibited excellent performance.

Ultraviolet surface-enhanced Raman scattering (UV-SERS) typically occupies an important position because the electronic absorption bands of many biomolecules are located in the deep-ultraviolet (DUV) or ultraviolet (UV) region. Practical application of UV-SERS still relies on uniform, reproducible, and affordable substrates. The conventional aluminum (Al) plasmonic nanostructures are mostly applied to act as UV-SERS substrates, but their intrinsic ohmic loss hinders their practical application. In this study, wafer-scale hybrid metal-dielectric gratings (HMDGs) consisting of aluminum and silicon (Al-Si) have been successfully fabricated as UV-SERS substrates to reduce ohmic dissipation and elevate the detection performance. Well-defined HMDG substrates exhibit tunable hybrid resonant modes in the UV and the visible regions. The adenine biomolecules deposited on HMDG substrates are used to perform SERS measurement with an excitation wavelength of 325 nm. The HMDG nanostructures can obtain as high as 5 orders of magnitude compared with that of Al film as UV-SERS substrates. The proposed HMDG nanostructures have a great advantage in detecting important biomolecules as UV-SERS substrates.

The thermodynamic stability of uranium hydrides is of broad interest and fundamental importance for understanding the hydriding corrosion of uranium, and the storage and isotope separation of hydrogen. Based on the first-principles calculations, we reveal the initial decomposition mechanism, interpret the experimental pyrolysis results, and discuss the inverse effects of temperature and hydrogen pressure ( P H 2 ) on the thermodynamic stability of β-UH 3 . The decomposition mechanism of β-UH 3 is found to be closely related to the changes of U-H bonding properties in UH 12 cages. Specifically, at the beginning it is difficult to break the first U-H covalent bond in each UH 12 cage, which brings in the existence of a concave region in the experimental P H 2 - C - T curve; however, it boosts the itinerant character of U-5f electrons. Thereafter, the formation energy of H-vacancies in the degraded UH 11 cages is almost changeless when the H/U atom ratio decreases, resulting in the van't Hoff plateau of the P H 2 - C - T curve. Based on the above mechanisms, we propose a theoretical method to evaluate the thermodynamic stability of β-UH 3 . The calculated P H 2 - C - T curve is consistent with experiment, showing that temperature promotes β-UH 3 decomposition and P H 2 plays an opposite role. Moreover, this method is independent of experimental calibration and is applied to discuss the isotope effect of hydrogen in β-UH 3 . This work provides new insight and a practical method for the scientific studies of uranium hydride, which is also essential to industrial applications in hydrogen isotope separation.

A novel near-infrared (NIR) fluorescent probe CHC-CES1 based on a hemi-cyanine skeleton for detecting carboxylesterase 1 (CES1) activity was developed. Herein, CHC-CES1 could be specifically hydrolysed to CHC-COOH along with a significant NIR fluorescence signal enhancement at 670 nm. Systematic evaluation indicated that CHC-CES1 possessed an outstanding selectivity and sensitivity towards CES1, and possessed good chemical stability in complex biosamples. Finally, CHC-CES1 was successfully used for the real-time imaging of endogenous CES1 activity in living cells. Moreover, CHC-CES1 was applied to evaluate the inhibitory effects of various pesticides towards CES1, and visually revealed the inhibitory effect of combined residue pesticides.

An unacceptable bitter taste limits the application of luteolin in healthier food systems. In this study, a bitterness-masking assessment was performed on whey protein isolate-coated liposomes loaded with luteolin (WPI-coated liposomes) using an electronic tongue and human sensory test. The physical properties of the WPI-coated colloidal nanocarrier were characterized by zeta potential, average diameter, distribution, and morphology analyses. The results indicated that WPI-coated nanocarrier systems exhibited a uniformly dispersed distribution and spherical morphology. After the comparison of the bitterness value, the bitterness-reducing effect of 5% WPI-coated liposomes was the most significant and reduced the bitterness of luteolin by 75%. Raman spectroscopy and X-ray diffraction analysis demonstrated that the decoration of WPI on the liposomes reduced the free motion of lipid molecules. This promoted the ordering at the polar headgroup area and hydrophobic core of the lipid bilayer, which explained why luteolin-loaded liposomes (uncoated liposomes) and WPI-coated liposomes could reduce the bitterness of luteolin from the perspective of bitter molecular groups. Combined with the Raman spectral data, the bilayer rigidity of 5% WPI-coated liposomes was positively responsive to the stabilization of uncoated liposomes against storage and resistance ability against surfactants. It was proven that the emergence of the surface modification of the WPI coating enhanced the stability of uncoated liposomes. These results may contribute to the use of WPI-coated liposomes as prospective candidates for effective delivery of the bioactive bitter substance in nutraceuticals and functional foods.

Glycerol monolaurate (GML) is a food safe emulsifier and a kind of MCFA monoglyceride that has been proven to confer positive benefits in improving animal health, production and feed digestibility as a feed additive. This study aims to evaluate whether supplementation of a sow diet with GML could affect the intestinal barrier function and antioxidant status of newborn piglets and to explore its regulatory mechanism. A total of 80 multiparous sows were divided into two groups, which were fed a basal diet or a basal diet supplemented with 0.1% GML. The results indicated that maternal supplementation with GML significantly increased fat, lactose and protein in sow colostrum, as well as fat and protein in sow 14-day milk ( P < 0.05). The results showed that GML significantly reduced the concentrations of IL-12 in the duodenum, TNF-α, IL-1β and IL-12 in the jejunum, and IL-1β in the ileum of piglets ( P < 0.05). Higher concentrations of T-AOC, T-SOD, GSH and GSH-Px and lower MDA in the intestine were observed in the GML group than in the control group. Correspondingly, the villi height, crypt depth and the ratio of villi height to crypt depth (V/C) in the jejunum and the V/C in the ileum in the GML group were significantly higher than those in the control group ( P < 0.05). Moreover, the GML group displayed significantly increased protein abundance of zonula occludens (ZO)-1, occludin, and claudin-1 in the small intestine ( P < 0.05), mRNA expression of mucins (MUCs) in the small intestine ( MUC-1 , MUC-3 and MUC-4 ), and mRNA expression of porcine beta defensins (pBDs) in the duodenum ( pBD1 and pBD2 ), jejunum ( pBD1 , pBD2 and pBD129 ) ( P < 0.05), and ileum ( pBD2 , pBD3 and pBD114 ) ( P < 0.05). Further research showed that GML significantly reduced the phosphorylation of the NF-κB/MAPK pathways in the small intestine ( P < 0.05). In addition, the results of 16S rDNA sequencing showed that maternal supplementation with GML altered the colonic microbiotic structure of piglets, and reduced the relative abundance of Escherichia shigella . In summary, a sow diet supplemented with GML enhanced the offspring's intestinal oxidative stability and barrier function and attenuated the offspring's intestinal inflammatory response, possibly by suppressing the activation of the NF-κB/MAPK pathways.

Coumarin acting as an optical probe was modified on ethylenediamine β-cyclodextrin, which not only enhanced its molecular binding affinity to glutathione (GSH) by a reversible Michael addition, showing 113 times more affinity than that of coumarin itself, but also achieved dynamic real-time sensing of glutathione in living HeLa cells.

Hypoxic and acidic environments are the two main components of the microenvironment contributing to the poor efficacy of chemotherapy drugs in the treatment of oral squamous cell carcinoma (OSCC). In this study, we synthesized a series of Zn 1- x Mg x Fe 2 O 4 nanomaterials with enzyme-like properties, including catalase (CAT)-like, peroxidase (POD)-like, and glutathione (GSH)-like activity in an acidic environment. Among them, Zn 0.4 Mg 0.6 Fe 2 O 4 performed the best and effectively increased the efficacy of doxorubicin (DOX) chemotherapy for the treatment of OSCC with reduced cardiotoxicity. Therefore, Zn 0.4 Mg 0.6 Fe 2 O 4 could serve as a novel chemosensitizer in the treatment of OSCC., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Nano-network Ru with definite lattice defects on amorphous Co nanosheets is obtained for the first time. Amorphous Co support can promote the surface Ru to obtain special morphology and modified electronic structure, thus improving HER activity in alkaline solution. A current density of 10 mA cm -2 can be obtained only with an overpotential of 33.5 mV.

The increasing importance of surfactants in various fields has led to growing interest in the comprehensive characterization of surfactants. The critical micelle concentration (CMC), the most fundamental property of surfactants, is a parameter that must be measured. In particular, with the continuous expansion of the molecular structure of surfactants, numerous novel amphiphilic molecules have been developed that are capable of forming ordered aggregates in various solvent systems. Fluorescence spectroscopy, based on the differences in fluorescence intensity and wavelength of the fluorescent probe in the solvent phase and micellar phase, can sensitively detect the CMC of surfactants. This review aims to summarize the various fluorescence methods used to determine the CMC, including aggregation-induced emission (AIE), excimer formation, intramolecular charge transfer (ICT), and other miscellaneous strategies. The difficulties and limitations in the CMC determination process are also described. Further suggestions are provided to guide the existing fluorescence probes and the corresponding fluorescence methods to detect critical aggregation concentrations of amphiphilic molecules.

Superconductivity with an unusual filamented character below 2 K has been reported in bulk ZrTe 3 crystals, a well-known charge density wave (CDW) material, but still lacks in its nanostructures. Here, we systemically investigated the transport properties of controllable chemical vapor transport synthesized ZrTe 3- x nanoplates. Intriguingly, superconducting behavior is found at T c = 3.4 K and can be understood by the suppression of CDW due to the atomic disorder formed by Te vacancies. Magnetic field and angle dependent upper critical field revealed that the superconductivity in the nanoplates exhibits a large anisotropy and two-dimensional character. This two-dimensional nature of superconductivity was further satisfactorily described using the Berezinsky-Kosterlitz-Thouless transition. Our results not only demonstrate the critical role of Te vacancies for superconductivity in ZrTe 3- x nanoplates, but also provide a promising platform to explore the exotic physics in the nanostructure devices., Competing Interests: The authors have no conflicts of interests., (This journal is © The Royal Society of Chemistry.)

The coordination of the B-H bond to a transition metal is fundamentally intriguing due to its connection with the transition metal-mediated B-H bond activation mechanism and catalysis. Most of the reported examples are σ-borane/borate complexes containing one or two σ-B-H bonds. However, examples of compounds containing three σ-B-H bonds are still much rarer. Herein, we report a facile approach for the synthesis of rare transition metal tris(σ-B-H) borate complexes by the salt elimination protocol using [Cp*RuCl] 4 and lithium trihydroborates Li[ArBH 3 ] containing 2,6-disubstituted aryl groups. These complexes have remarkable thermal stability in solution. In addition, this novel class of compounds has the unusual σ-complex that features three labile σ-B-H bonds. Our studies on these new species demonstrate that the coordination σ-B-H bond can undergo H/D exchange with D 2 and ligand substitution reactions with PPh 3 , PCy 3 and IPr 2 Me 2 . These results provide new approaches for the synthesis of both tris(σ-B-H) borates and bis(σ-B-H) borates.

Ferroelectric materials are widely recognized for their ability to generate photovoltaic voltages larger than their bandgap, making them ideal candidates for photodetector applications. Here, we report a self-powered UV photodetector based on a Bi 0.5 Na 0.5 TiO 3 (BNT) thin film prepared by the sol-gel method. Compared with conventional photodetectors based on a single detection indicator, the demonstrated photodetector realizes UV light intensity detection over a wide linear range using a current and voltage dual indicator detection method. When the UV light intensity is lower than 1.8 mW cm -2 , the voltage can be used to detect the light signal. Conversely, the current can be utilized to detect the signal. This method not only broadens the linear detection range of UV light intensity, making it possible to detect weak UV light of 45.2 nW cm -2 , but also allows the detector to maintain relatively high sensitivity within the detectable range. To investigate the distribution of spatial UV light intensity, a self-powered photodetector array system has been utilized to record the output voltage signals as a map.

In this study, we studied the feasibility of preparing high-quality needle coke from coal liquefaction pitch. Nine types of blending pitch (coal liquefaction pitch and anthracene oil mixed with different ratios) were used as raw materials to generate needle coke via the co-carbonization method. Optical microscopy, X-ray diffraction, Raman spectroscopy and scanning electron microscopy were employed to determine the properties (microstructure, distribution of carbon microcrystals, true density and micro-strength) of the needle coke derived by the co-carbonization method. Actually, the co-carbonization of coal liquefaction pitch and anthracene oil was an essential method to control the micro-structure and property of the derived needle coke. Briefly, the needle coke derived by the co-carbonization of coal liquefaction pitch and anthracene oil had a lower content of mosaic structure of 14.17%, ideal carbon crystal content of 82.67%, and true density of 2.296 g cm -3 . Briefly, the addition of anthracene oil is a suitable method to adjust the property of coal liquefaction pitch, which is also a good method to produce high-quality needle coke via the co-carbonization of coal liquefaction pitch and anthracene oil. Thus, the use of coal liquefaction pitch and anthracene oil as raw materials to generate high-quality needle coke is a considerable method to realize the clean and high value-added utilization of coal liquefaction pitch., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (This journal is © The Royal Society of Chemistry.)

Herein, we describe a novel O 2 N˙-triggered ordered addition 7- endo cyclization reaction with excellent chemo- and regioselectivity. With such a strategy, structurally diverse nitro-benzo[ b ]azepines were prepared with 28 examples. Large-scale operation and handy N -Ts and N -Cbz deprotection reveal the promising utility of this methodology. Mechanistic studies suggest that the reaction proceeds through a radical pathway.

We report a general protocol for ortho -C-H fluoroalkoxylation of benzaldehydes and benzylic amines utilizing an inexpensive amino amide as a transient directing group. In the presence of an electrophilic fluorinating bystanding oxidant and fluorinated alcohols, a wide range of benzaldehydes and benzylic amines could be oxygenated selectively at the ortho positions to afford fluoroalkyl aryl ethers. This elegant approach would provide appealing strategies for synthesis of drug molecules and natural products., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The aims of this study were to evaluate whether a diet supplemented with glyceryl butyrate could attenuate the immune-inflammatory response in piglets challenged with enterotoxigenic Escherichia coli (ETEC), and to explore the mechanisms of its regulation. Eighteen weaning piglets were assigned to three diets: basal diet (CON), antibiotics diet (ATB), and 0.5% glyceryl butyrate diet (GB group). Significantly lower concentrations of IL-1β, IL-6 and TNF-α in the jejunum and IL-6 in the ileum were observed in the GB group than that in the CON group ( P < 0.05). Moreover, a decreasing trend of IL-1β ( P = 0.075) and TNF-α ( P = 0.070) was observed in the ileum in the GB group. Correspondingly, the GB group had significantly increased mRNA expression of porcine beta defensins (pBDs) in the jejunum (pBD1, pBD2, pBD114 and pBD129) and ileum (pBD2, pBD3, pBD114 and pBD129) ( P < 0.05), and protein abundance of Claudin 1, Occludin, and ZO-1 in the jejunum and ileum ( P < 0.05). Further research results showed that the improvement of beta defensins and tight junctions in the GB group was related to the decreased phosphorylation of the NFκB/MAPK pathway. In addition, the results of 16S rDNA sequencing showed that glycerol butyrate supplementation altered the ileal microbiota composition of piglets, increasing the relative abundance of Lactobacillus reuteri , Lactobacillus salivarius , and Lactobacillus agrilis . In summary, glyceryl butyrate attenuated the immune-inflammatory response in piglets challenged with ETEC by inhibiting the NF-κB/MAPK pathways and modulating the gut microbiota, and thus improved piglet intestinal health.

A nano Ir x Mn (1- x ) O y hybrid electrode with a L1 2 -IrMn 3 phase was used as a bifunctional catalyst with ultra-low iridium loading for overall water electrolysis in an acid solution for the first time. The HER activity of the Ir x Mn (1- x ) O y hybrid electrode not only exceeded that of IrO 2 , but also exceeded that of Pt/C. The OER activity of the Ir x Mn (1- x ) O y hybrid electrode also exceeded that of IrO 2 .

Luteolin (LTL) is a flavonoid containing a cis -diol, which has significant anti-inflammatory, anti-allergic, anti-diabetic, anti-cancer and neuroprotective activities. In this work, a silver modified boric acid affinity polyvinyl imine (PEI) dendritic adsorbent (PPEI-Ag@CPBA) was prepared on polystyrene (PS) for the rapid recognition and selective separation of LTL. A thin layer of polydopamine (PDA) was formed on the surface of the substrate by self-polymerization, and a PDA-coated PS material (PS@PDA) was obtained. PEI with sufficient active amino groups was grafted onto PS@PDA to obtain a PEI-modified material (PS@PDA@PEI), then AgNO 3 was reduced with NaBH 4 , and PS@PDA@PEI was embedded on Ag. Finally, PPEI-Ag@CPBA was obtained through the condensation reaction of PEI with 4-carboxyphenyl boric acid (CPBA). The adsorption conditions were optimized, the optimal pH and the optimum amount of adsorbent were determined, and the maximum adsorption capacity was found to be 2.49 mg g -1 . This method has been successfully applied to the selective identification of LTL in peanut shell samples, and provides a practical platform for the detection of LTL in complex substrates., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In recent years, it has been found that Cu 2+ , Fe 3+ , and amino acids play an irreplaceable and subtle role in organisms and have attracted the considerable attention of many researchers. Therefore, it is vital to design visual indicators to reveal the relationships between metal ions and amino acids. However, there have been few reports on this vigorous subject. Fortunately, based on the different coordination effects between metal ions and boron groups, we have designed an accessible fluorescent probe (PSI-A). Borane was introduced as an ion-sensitive group to form a novel POSS-based fluorescent probe, which achieves fascinating performance, in situ dynamic multiple detection, excellent photostability, and enervative biological toxicity. PSI-A exhibited predominant selectivity and sensitivity to Cu 2+ /amino acids and Fe 3+ /amino acids sequence reactions in HepG2 cells and zebrafish. The fluorescence of PSI-A was quenched by Cu 2+ , which can be recovered by adding Asp, Ser, Arg, Ace or Trp. Additionally, the fluorescence of PSI-A quenched by Fe 3+ can be restored after adding Asp. PSI-A is available to monitor Cu 2+ /amino acids and Fe 3+ /amino acids sequence reactions and can be repeated for at least three consecutive cycles without a fatigued performance. Therefore, this multifunctional fluorescent probe may have prospective application potentials in the biological field.

A series of microporous Ln(III)-based metal-organic frameworks (1-Ln) have been hydrothermally synthesized using 4,4',4''-nitrilotribenzoic acid (H 3 NTB). Single crystal X-ray diffraction analyses show that 1-Ln are isostructural and have 3D porous frameworks with remarkable stability and permanent porosity for Ar and CO 2 adsorption. In addition, 1-Ln exhibit diverse photoluminescence emissions depending on the nature of lanthanide ions. More importantly, 1-Ln are further studied in the Knoevenagel reactions of benzaldehyde derivatives and malononitrile under solvent-free conditions, and it is found that 1-Tb shows the best catalytic activities (yields up to 99%), providing a unique example to differentiate the roles of Ln ions within the frameworks in catalyzing Knoevenagel reactions.

Endogenous H 2 O 2 generated by a single HeLa cell that was adhered on the PDA-coated PDMS substrates under 25 mM glucose culture conditions was detected using a home-built photoelectric dual detection platform. With PMA as the stimulus, the cell released a small amount of H 2 O 2 and its mitochondrial membrane potential (MMP) decrease was smaller, compared with that on the PDMS substrates.

Flexible touch-sensing devices have attracted extensive attention in wearable electronics and human-machine interaction. The ionic touch-sensing hydrogels are ideal candidates for these scenarios, but the absorbed water evaporates easily from the hydrogel, reducing their working time and stability. Herein, we propose a touch-sensing fabric system composed of non-woven cellulose fabrics as a sheath shell layer encapsulated with a hydrogel filling layer. The resultant touch-sensing fabric has a super-thin structure (1 mm) and exhibits a low detecting threshold (50 Pa), high durability (100k times), strain/pressure insensitivity and extremely high touch positioning accuracy. In the proof of concept, a smart touch-sensing glove is equipped with our fabric, which can execute human-computer interaction as a flexible touch-sensing device.

Lithium reagents have long played important roles in synthetic chemistry. However, unsaturated organosilicon lithium reagents are few in number. Herein, we describe the first isolation of a 1,2-dilithiodisilene: [(boryl)SiLi] 2 ( 2 ) was prepared in 73% yield by the reduction of (boryl)tribromosilane ( 1 , boryl = (HCArN) 2 B, Ar = 2,6-iPr 2 C 6 H 3 ) with lithium in Et 2 O. The salt elimination reaction of 2 with dihaloboranes RBX 2 afforded disilaborirenes [(boryl)Si] 2 BR ( 3a-c ), whereas the reaction with two equivalents of B -bromocatecholborane ((cat)BBr) yielded the first tetraboryldisilene [(boryl)(cat)BSi] 2 ( 4 ). X-ray diffraction analysis and density functional theory calculations indicated that the disilene 2 and tetraboryldisilene 4 feature an almost planar geometry and disilaborirenes 3a-c are aromatic with a silicon-boron hybrid 2π-electron delocalized structure. The results indicate that 1,2-dilithiodisilene 2 is a powerful synthetic reagent for the construction of novel silicon multiply bonded species with unique electronic structures and that the boryl substituents have significant electronic effects on the structure of silicon multiple bonding., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Multifunctional self-healing hydrogels have recently attracted considerable interest in biomedical applications owing to their diverse properties, including self-healing, adhesion, conduction, antibacterial, and stimulus-response, which can meet various application requirements, ranging from wound dressings and delivery vehicles to the production of scaffolds for tissue repair and regeneration. As a natural polycationic polysaccharide with good biocompatibility, chitosan is widely used in hydrogel formation as there are many amino and hydroxyl groups along the chains that can actively participate in various physical effects and chemical reactions, which enable it to construct self-healing hydrogels and fulfill multiple functions. In this review, the formation of chitosan-based self-healing hydrogels and the related self-healing mechanism are summarized, including Schiff base, metal coordination, ionic and hydrogen bonds, hydrophobic and host-guest interactions, with a focus on the strategies for their multi-functionalization. In the last section, the applications of the chitosan-based self-healing hydrogels in the fields of wound dressings, delivery vehicles, scaffolds, and biological sensors are discussed. Overall, it is highly expected that this review could provide an insight into the prospective development of multifunctional self-healing hydrogels for biomedical applications.

The pressure-dependent photoluminescence kinetics of CsPbBr 3 :Ce quantum dots was investigated by steady-state and time-resolved photoluminescence spectroscopy. Here, we propose a novel strategy to improve the persistent luminescence of CsPbBr 3 quantum dots under high pressure through doping of Ce 3+ ions. Under high pressure, the peak intensity and energy of CsPbBr 3 :Ce quantum dots decreased more slowly than those of CsPbBr 3 quantum dots, which is manifested by pressure coefficient reductions of 0.08 a.u. GPa -1 and 0.012 eV GPa -1 , respectively. The time-resolved photoluminescence measurements revealed that Ce 3+ -doping can significantly modulate the photoluminescence kinetics to shorten the lifetimes of CsPbBr 3 quantum dots with increasing pressure. These phenomena were absolutely different from those observed in CsPbBr 3 quantum dots. These findings will be useful for broadening the application of optical devices based on all-inorganic perovskite materials under high pressure.

Fatty acid amide hydrolase (FAAH) is primarily responsible for the inactivation of fatty acid ethanolamide (FAE) and is involved in a variety of biological functions related to diseases of the nervous system. Herein, we developed a highly selective and sensitive FAAH-activated near-infrared fluorescent probe named DAND and achieved the real-time detection and imaging of FAAH activity in complex biosystems. Moreover, a visual high-throughput screening method was established using DAND, piperine was identified as a novel inhibitor of FAAH. Based on the interaction of piperine with FAAH, a more potent FAAH inhibitor (11f) was designed and synthesized which possessed an IC 50 value of 0.65 μM. Furthermore, 11f could attenuate the liposaccharide (LPS)-induced activation of BV2 cells, exhibiting an excellent anti-inflammatory activity. These results indicated that DAND could be used as a promising molecular tool for exploring FAAH activity and for rapidly screening potential FAAH inhibitors. In addition, piperine and its derivatives could serve as potential candidate drugs for the treatment of neurodegenerative diseases in the future.

The great interest in using nanoparticles (NPs) for biomedical applications is transversal to various materials despite the poorly understood correlation between their physicochemical properties and effects on the immune system. NPs, such as gold and Fe 3 O 4 , are generally regarded as safe, but the immunotoxicological profile of Au/Fe 3 O 4 composite NPs with different physicochemical properties is not well documented. This study investigated the biological impact of Au/Fe 3 O 4 composite NPs with different morphologies (spherical core-shell and flower-like) and shell composition in vitro to analyze their potential cytotoxic effects and inflammatory responses on RAW 264.7 cells. Au/Fe 3 O 4 composite NPs with a flower-like structure (FLNPs) induce a pronounced reduction in cell viability compared with Au/Fe 3 O 4 composite NPs with a spherical core-shell structure (CSNPs). The increased production of reactive oxygen species, which damages cellular membranes, might contribute to the cytotoxicity effect of FLNPs. However, CSNPs presented more RAW 264.7 cell adhesion and uptake than FLNPs. Remarkably, a significant TNF-α release was observed with CSNP treated RAW 264.7 cells other than that of FLNPs. Protein corona analysis revealed the adsorption of a distinct amount and profile of proteins on the surface of CSNPs and FLNPs. Given the similar particle size and ζ-potential of CSNPs and FLNPs under the cell culture condition, results indicate that the impact of Au/Fe 3 O 4 composite NPs on the macrophage activity highly depends on their morphology, shell composition and protein corona profile.

Hydrogels are cross-linked hydrophilic macromolecules that contain a certain amount of water. Due to their biocompatible, highly tunable and hydrophilic nature, hydrogels have attracted much attention in the applications of chemical, biomedical and pharmaceutical fields over the past twenty years. In particular, thermo-sensitive hydrogels, which can undergo phase transition or swell/deswell as ambient temperature changes, endow the drug delivery system with enhanced local drug penetration, desirable spatial and temporal control, and improved drug bioavailability. These merits facilitate their extensive applications in drug delivery. In this review, we focus on advances in the development of different thermo-sensitive polymers as a scaffold for drug delivery, including poly(N-isopropylacrylamide) (pNIPAAM), poloxamer, polyethylene glycol/poly(lactic acid)co-(glycolic acid) (PEG/PLGA), and chitosan. The state-of-the-art thermo-sensitive hydrogels for various pharmaceutical applications, such as anti-tumor drug delivery, transdermal drug delivery, ocular drug delivery, nasal drug delivery, and buccal drug delivery, are elaborated. Finally, the future research perspectives and challenges are also discussed, which could facilitate the translation of thermo-sensitive hydrogels for drug delivery from bench to bedside.

Demineralized bone matrix (DBM) powder is a potential alternative bone grafting material due to its bone regeneration capacity when the supply of autogenous bone is insufficient. However, the use of DBM powder alone remains challenging in many aspects in the clinic, such as its unstable osteoinductivity due to inactivation of growth factors during the preparation process, lack of bone regeneration cells, and difficulty in handling. Herein, we report a strategy that adopts a dual delivery of DBM powder and hypoxia-pretreated bone marrow stromal cells (BMSCs) using an injectable self-healing hydrogel to enhance bone regeneration and repair a cranial bone defect in a rabbit model. The injectable self-healing hydrogel was prepared based on a double crosslinking architecture, which comprised a dynamically cross-linked Schiff-base network as a self-healing component and a borax ion cross-linked physical network that strengthened its mechanical properties. The handling of the DBM powder was improved by mixing with the hydrogel, and, more importantly, the expression of osteocalcin (OCN) and vascular endothelial growth factor (VEGF) of the encapsulated BMSCs in the hydrogel was significantly up-regulated after hypoxia-pretreatment. The in vivo study demonstrated that the use of the hydrogel alone cannot heal the cranial bone defect, while the hydrogel/BMSC composite could increase the bone formation but was inferior to the hydrogel/DBM composite. Finally, the hydrogel/DBM/BMSC composite exhibited the best bone defect repairing effects among all groups. Overall, our results demonstrate that this dual delivery approach is a promising strategy to enhance bone regeneration for bone defect repair.

Two novel lathyrane-type diterpenoids, the Euphorbia factors L 2a (1) and L 2b (2), and their stereoisomer Euphorbia factor L 2 (3) were obtained from seeds of Euphorbia lathyris . Both Euphorbia factors L 2a and L 2b possess an unprecedented trans-gem -dimethylcyclopropane as structural feature. Also, the Euphorbia factor L 2a is the first example of a lathyrane diterpenoid with an endocyclic 12( Z )-double bond. The structures of the molecules and their absolute configurations were elucidated by comprehensive spectroscopic analyses, Cu-Kα radiation X-ray diffraction, and comparison with calculated electronic circular dichroism (ECD) data. The Euphorbia factor L 2b exhibited an inhibitory effect against U937 cell line with an IC 50 value of 0.87 μM., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A series of metal silicates, NaMSi 10 Ox (M = Cu, Mn and Ni), were prepared by in situ doping of metals into mesoporous SBA-15 under a hydrothermal process, displaying a continuous framework of SiO 4 structure with a narrow pore size distribution. These metal silicate materials were tested for CO 2 adsorption behavior in the absence and presence of water. The results exhibited that the effect of H 2 O on the CO 2 capture capability of metal silicates depends on the types of metal inserted into SBA-15. Compared to the dry condition, H 2 O addition enhances CO 2 uptake dramatically for NaCuSi 10 Ox by 25%, and slightly for NaNiSi 10 Ox (∼10%), whereas little effect is shown on NaMnSi 10 Ox. The metal silicate materials are stable after adsorption of CO 2 under wet conditions, which is benefited from their synthesis method, hydrothermal conditions. The improvement of CO 2 uptake on metal silicates by H 2 O is attributed to the competitive and synergistic adsorption mechanism on the basis of IR investigations, where initially adsorbed H 2 O acts as a promoter for further CO 2 capture through a hydration reaction, i.e. , formation of bicarbonate and carbonates on the surface of the samples. These observations provide new possibilities for the design and synthesis of porous metal silicate materials for CO 2 capture under practical conditions where moisture is present., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Plasmonic nanoparticles with special localized surface plasmon resonance (LSPR) characters have been widely applied for optical sensing of various targets. With the combination of single nanoparticle imaging techniques, dynamic information of reactions and biological processes is obtained, facilitating the deep understanding of their principle and design of outstanding nanomaterials. In this review, we summarize the recently adopted optical analysis of diverse analytes based on plasmonic nanoparticles both in homogeneous solution and at the single-nanoparticle level. A brief introduction of LSPR is first discussed. Colorimetric and fluorimetric homogeneous detection examples by using different sensing mechanisms and strategies are provided. Single plasmonic nanoparticle-based analysis is concluded in two aspects: visualization of chemical reactions and understanding of biological processes. The basic sensing mechanisms and performances of these systems are introduced. Finally, this review highlights the challenges and future trend of plasmonic nanoparticle-based optical analysis systems.

The determination of trace-amount organotins in plastic food packaging materials is of great significance in food safety. However, due to the complexity of organotins and sample treatment processes, it is still a challenging task. Here, we report a method for the sensitive and simultaneous determination of organotins in plastic food packaging materials and edible oils, by utilizing sheathless capillary electrophoresis-electrospray ionization-mass spectrometry. The method of sample pretreatment with ultrasonic extraction and solid phase extraction is used to eliminate interference. The results showed low limits of detection (LODs) of 2 pg mL -1 -50 pg mL -1 and excellent inter/intra-day repeatability. Good average recoveries in the range of 80.27% to 108.52% were obtained at three spiked concentrations, with a relative standard deviation less than 8.71%. The successful simultaneous determination of the target analytes will pave the way for further assessment of contamination and migration behaviour of organotins from packaging materials to food, which is of great significance for evaluating and controlling food safety.

Amyloid fibrils, implicated in health and diseases, commonly exhibit a periodic twist trait relevant to the structures and dynamics of the fibrils. However, the origins and modulations of fibril twist in complex in vivo environments are not yet fully understood. Here we highlight an important factor that causes twist variations in amyloid fibril structures-the presence of surrounding surfaces. Using cholesterol-containing lipid bilayers with varying cholesterol contents, we have demonstrated via atomic force microscopy that amyloid-β peptide fibrils initiated on membranes increase their average pitch size of twisting periodicity as the cholesterol content increases. These surface-induced twist variations arise from the enhanced hydrophobic interactions between the fibril and the surface distorting the torsional elastic energy of the fibril twisting as supported by a theory of an elastic model. These findings not only provide an important insight into fibril polymorphism phenomena resulting from the surface effects but also suggest a novel solution to modulate filament twisting on the nanoscale for biomaterials applications involving nanoscale features.

Contradictive to the conventional wisdom that a collapsed polymer globule in poor solvents adsorb on surfaces in a way analogous to the spreading of a liquid droplet, here we have shown via single molecule measurements that a single poly(N-isoporpylacrylamide) (PNIPAM) globule can jump from one spot to another as an elastic nonadhesive ball even on a hydrophobic polystyrene surface. The molecular weight dependence of the effective surface diffusion coefficient measured for the adsorbed globule suggested that it exhibited mostly a similar globular conformation to that in the bulk solution. Both the displacement and waiting time distributions of the adsorbed globules were found to follow a power-law decay rather than an exponential process, suggesting a broad distribution of binding energies due to the difference in degree of globule deformation. These effects together reflect a character of the viscoelasticity even in a single-chain globule in dilute solutions. Our findings also demonstrate that it is not the single-chain globule but the inter-globule aggregates at high concentration that lead to irreversible adsorption on the surface, which provides novel dynamics and mechanisms of how a thermosensitive polymer adsorbs on the hydrophobic surface above its lower critical solution temperature.

It is well-known that a fine dispersed rubber phase in thermoplastic vulcanizates (TPVs) is a key to obtain good mechanical properties and high elasticity of TPV products. Previous studies reported that the rubber nanodroplets formed during shearing blending can transform into rubber nanoparticles by in situ rapid crosslinking and these rubber nanoparticles spontaneously form agglomerates dispersed in a plastic matrix during dynamic vulcanization (DV). However, important influencing factors on the formation of rubber nanoparticles and their agglomeration during DV have not been reported yet. In this study, the coupling effect of the molecular weight (MW) of polypropylene (PP) and crosslinking kinetics including the crosslinking rate (CR) and crosslinking degree (CD) on the size of ethylene propylene diene monomer (EPDM) rubber nanoparticles and their agglomerates in EPDM/PP TPVs was systematically studied for the first time. The minimum diameter of EPDM nanodroplets was theoretically calculated by using the critical break-up law of viscoelastic melts for the blend with high MW PP or the critical capillary equation for the blend with low MW PP, and the real size of the EPDM nanoparticles was experimentally verified. Interestingly, the results show that the lower MW of the PP phase, lower CD and higher CR contribute to the formation of smaller rubber nanoparticles, whereas the higher MW of the PP phase and higher CD of the rubber phase contribute to the formation of smaller rubber nanoparticle agglomerates. This study provides guidance to optimize the microstructure of EPDM/PP TPVs for the preparation of high-performance TPV products.

In this study, gemini ammonium sulfobetaine (GAS) is designed and synthesized using isophorone diisocyanate connecting the ammonium sulfobetaines (AS) to obtain a viscoelastic surfactant exhibiting better viscosification and salt resistance. AS is prepared using the monomers of erucic acid, N -dimethyl-1,3-propanediamine, and 3-chloro-2-hydroxypropanesulfonic acid sodium. The properties of GAS and its proppant suspension as well as the gel-breaking mechanisms are investigated. The critical micelle concentration of GAS is 2.1 × 10 -7 mol mL -1 . GAS exhibits good salt resistance, and the viscosity is considerably high under acidic conditions. At 0.5 Hz, the storage modulus G ' of GAS is 60, 120, and 640 mPa when the concentration is 0.3, 0.5, and 1.0 wt%, respectively. Its proppant suspension is optimal under acidic conditions. When the pH is high, the setting velocities are clearly observed to increase. When the pH is 12, the rate of decline is more than 50% after 200 min. Some of the worm-like micelles adsorbed on the proppant surface participate in the formation of the three-dimensional network, appropriately supporting the proppant-carrying performance. When potassium permanganate is used as the gel breaker, the characterization of the GAS gel-breaking liquid indicates that the double bond is disintegrrated by the gel breaker. Upon gel breaking, the average hydrodynamic radius of the GAS gel-breaking solution decreases to 176.2 nm from 492.3 nm., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Photothermal therapy (PTT) is a highly selective and non-invasive method to remove tumor tissues, and a promising potential method to combat cancer in the near future. However, the physical changes inside cells during photo-induced cell death have not been studied yet, due to the lack of proper tools. In this work, a polarity-sensitive PTT sensitizer was fabricated for the first time, to investigate the intracellular polarity change during photo-induced cell death. The probe targets mitochondria in live cells and can detect the polarity change induced by the addition of cholesterol in a ratiometric manner. The cell viability of live Hepg2 cells pre-incubated with the probe could be dramatically decreased after laser irradiation within 5 min. The down-regulated mitochondrial polarity during photo-induced cell death was successfully revealed by using the probe.

Herein, to control the particle size of metatitanic acid produced via titanium thermal hydrolysis in sulfuric-chloric mixture acid (SCMA) solutions, the relationship between its grain size and hydrolysis parameters is discussed, and the corresponding mathematical model was established using the experimental data. Firstly, Ti(OH)(SO 4 )(Cl)(H 2 O) 3 was selected as the most likely initial structure in the SCMA solution by comparing the experimental and corresponding simulated Raman spectra by density functional theory (DFT). Secondly, according to the predicted initial structure of TiO 2+ and the experimental data for the hydrolysis process, with an increase in the concentration of TiO 2+ and reaction temperature, the hydrolysis rate and grain size increased, while the agglomerate particle size decreased. Finally, a mathematic model was established and fitted by the Arrhenius equation and the Boltzmann distribution to describe the relationship between the grain size and hydrolysis parameters, as follows., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this communication, the mechanism of how surface chirality affects amyloid-β (Aβ) fibrillation was firstly unravelled at the molecular level: a chiral surface serves to control the 2D-diffusion and surface residence time of Aβ molecules via the chiral recognition with Aβ to allow precursor Aβ to laterally diffuse and collide with each other for oligomerization and fibrillation. Surface chirality that shortens the surface residence time of Aβ, for example, R-cysteine modification with carboxylic, secondary amine and thiol groups surrounding the chiral center, can retard Aβ oligomerization and fibrillation. This work is essential to a deeper fundamental understanding of the effects of surface chirality on amyloidosis processes as well as the development of chiral materials to inhibit Aβ fibrillation.

In this work, a unique dual-site controlled fluorescent probe was presented for the sensitive and concurrent detection of pH in the cytoplasm and lysosomes. With the probe, the simultaneous down-regulation of pH in the lysosomes and cytoplasm during autophagy has been successfully revealed for the first time.