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Triple negative breast cancer (TNBC) is one of the most malignant subtypes of breast cancer. Here, we report the construction of graphene nanoribbon (GNR)-based supramolecular ensembles with dual-receptor (mannose and αvβ3 integrin receptors) targeting function, denoted as GNR-Man/PRGD, for targeted photothermal treatment (PTT) of TNBC. The GNR-Man/PRGD ensembles were constructed through the solution-based self-assembly of mannose-grafted GNRs (GNR-Man) with a pyrene-tagged αvβ3 integrin ligand (PRGD). Enhanced PTT efficacies were achieved both in vitro and in vivo compared to that of the non-targeting equivalents. Tumor-bearing live mice were administered (tail vein) with GNR-Man/PRGD and then each mice group was subjected to PTT. Remarkably, GNR-Man/PRGD induced complete ablation of the solid tumors, and no tumor regrowth was observed over a period of 15 days. This study demonstrates a new and promising platform for the development of photothermal nanomaterials for targeted tumor therapy., Dual receptor-targeting supramolecular glycomaterials are constructed based on graphene nanoribbons for the targeted photothermal therapy of triple-negative breast cancer in vivo.

With the ever-increasing threat posed by the multi-drug resistance of bacteria, the development of non-antibiotic agents for the broad-spectrum eradication of clinically prevalent superbugs remains a global challenge. Here, we demonstrate the simple supramolecular self-assembly of structurally defined graphene nanoribbons (GNRs) with a cationic porphyrin (Pp4N) to afford unique one-dimensional wire-like GNR superstructures coated with Pp4N nanoparticles. This Pp4N/GNR nanocomposite displays excellent dual-modal properties with significant reactive-oxygen-species (ROS) production (in photodynamic therapy) and temperature elevation (in photothermal therapy) upon light irradiation at 660 and 808 nm, respectively. This combined approach proved synergistic, providing an impressive antimicrobial effect that led to the complete annihilation of a wide spectrum of Gram-positive, Gram-negative, and drug-resistant bacteria both in vitro and in vivo. The study also unveils the promise of GNRs as a new platform to develop dual-modal antimicrobial agents that are able to overcome antibiotic resistance.

We report on a supramolecular sensor array using fluorogenic peptide probes and graphene oxide that can target glycoproteins on a viral caspid, facilitating the differentiation of ebola virus from marburg virus and receptor-extensive vesicular stomatitis virus using principal component analysis.

Bacterial infection is a major threat to human health. However, many antibacterial agents currently used are severely limited due to drug-resistance, and the development of side effects. Herein, we have developed a non-antibiotic nanocomposite consisting of chitosan (ChS) coated silver nanoparticles (AgNPs) and graphene nanoribbon (GNR)-based nanowires for light-triggered eradication of bacteria. The presence of AgNP/ChS significantly enhanced the interactions of the GNR nanowires with Pseudomonas aeruginosa, a clinically common Gram-negative bacterium. Which enables the highly effective photothermal eradication of bacteria by GNR upon near-infrared light irradiation. The nanocomposite was shown to be applicable for the light-triggered eradication of bacterial biofilms and the inhibition of bacterial growth on medical patches used for abdominal-wall hernia surgery.

Correction for ‘Fluorescent glycoconjugates and their applications’ by Baptiste Thomas et al., Chem. Soc. Rev., 2020, 49, 593–641, DOI: 10.1039/C8CS00118A.

Glycosidases, which are the enzymes responsible for the removal of residual monosaccharides from glycoconjugates, are involved in many different biological and pathological events. The ability to detect sensitively the activity and spatiotemporal distribution of glycosidases in cells will provide useful tools for disease diagnosis. However, the currently developed fluorogenic probes for glycosidases are generally based on the glycosylation of the phenol group of a donor–acceptor type fluorogen. This molecular scaffold has potential drawbacks in terms of substrate scope, sensitivity because of aggregation-caused quenching (ACQ), and the inability for long-term cell tracking. Here, we developed glycoclusters characterized by aggregation-induced emission (AIE) properties as a general platform for the sensing of a variety of glycosidases. To overcome the low chemical reactivity associated with phenol glycosylation, here we developed an AIE-based scaffold, which is composed of tetraphenylethylene conjugated with dicyanomethylene-4H-pyran (TPE–DCM) with a red fluorescence emission. Subsequently, a pair of dendritic linkages was introduced to both sides of the fluorophore, to which six copies of monosaccharides (d-glucose, d-galactose or l-fucose) were introduced through azide–alkyne click chemistry. The resulting AIE-active glycoclusters were shown to be capable of (1) fluorogenic sensing of a diverse range of glycosidases including β-d-galactosidase, β-d-glucosidase and α-l-fucosidase through the AIE mechanism, (2) fluorescence imaging of the endogenous glycosidase activities in healthy and cancer cells, and during cell senescence, and (3) glycosidase-activated, long-term imaging of cells. The present study provides a general strategy to the functional, in situ imaging of glycosidase activities through the multivalent display of sugar epitopes of interest onto properly designed AIE-active fluorogens., We report a general strategy for the fluorogenic sensing of glycosidases in cells based on aggregation-induced emission of glycoclusters.

Currently, chemotherapy is a widely used and important treatment for cancer. However, almost all of the treatments have shortcomings associated with poor specificity and high toxicity, which results in severe side effects to normal cells and tissue. This is a very important problem, and yet, it currently remains unanswered. Therefore, the development of the method for the more effective delivery of anticancer drugs to their targets and real-time monitoring of the localization of the drugs are very important. Herein, we designed a theranostic prodrug: CPT-p-Leu, which was constructed using fluorescent camptothecin (CPT), a self-immolative linker and leucine (Leu) residue. Upon exposure to LAP (leucine aminopeptidase: LAP), the amide bond in CPT-p-Leu will be cleaved, followed by an intramolecular 1,6-elimination, which triggers the active anticancer drug (CPT) release and recovers the fluorescence of CPT. With our design, the anticancer drug, CPT, can be used as both a drug and a fluorescence reporter, making our system suitable to accurately and effectively track the released CPT distribution. Based on this strategy, CPT-p-Leu could achieve the chemoselective detection of LAP and monitoring of the anticancer drug release. Furthermore, it also provides a very convenient way to accurately determine the location of the released drug in living samples. In addition, CPT-p-Leu shows a good cell membrane permeability and enhanced cytotoxicity toward LAP overexpressing cancer cells. We anticipate that our research will facilitate the development of improved theranostic systems for cancer therapy.

Carbon fiber (CF) is a promising material as carbon-based electrode and support for flexible supercapacitors. However, it still suffers from narrow voltage in the aqueous electrolyte due to the water decomposition (1.23 V). Herein, an aerobic pyrolysis is developed to recover aligned carbon fibers from carbon fiber reinforced polymers. More importantly, during this oxygen existence condition, the surface of reclaimed carbon fibers (RCFs) is etched into groove-shaped structure and modified by introducing abundant oxygen-containing functional groups, which significantly expands the negative potential window of RCFs-based electrode to −1.4 V (vs standard calomel electrode) and the working voltage of RCFs-based symmetric supercapacitor to 2.4 V in an aqueous electrolyte of 1.0 M Na2SO4, with capacitance retention of 90% and 93.6% after 10 000 cycles, respectively. This work well matches the aerobic pyrolysis of recovery of CFs from CFRPs and electrochemical performances of RCFs, supplying a new strategy to de...

The novel Tm3+/Sb3+ co-doped phosphate glasses are studied in response to an improvement of blue light emitting source. The analysis of J-O intensity parameters suggests that the present strontium phosphate glass is an appropriate matrix for Tm3+ doping to obtain an enhanced blue emission. The 5 s2-type Sb3+ ion serves as a sensitizer to transfer its strong allowed excitation in the deep UV region to Tm3+ effectively. PL and PLE spectra show that by Sb3+ co-doping, the blue emission of the Tm3+ doped strontium phosphate glass is enhanced greatly, while the excitation band of Tm3+ extends largely to the deep UV region. The emission decay curves of Sb3+ demonstrate the existence of the energy transfer (ET) process from Sb3+ to Tm3+ with the maximum efficiency and probability of ET as 20.43% and 9.20%, respectively. The emission color of these glasses can be adjusted from warm to cold blue via modulating excitation wavelengths. The present work suggests that Sb3+/Tm3+co-doped strontium phosphate glasses are promising for applications in blue emitters and plasma display panels.

The excessive use of antibiotics has led to a rise in drug-resistant bacteria. These "superbugs" are continuously emerging and becoming increasingly harder to treat. As a result, new and effective treatment protocols that have minimal risks of generating drug-resistant bacteria are urgently required. Advanced nanomaterials are particularly promising due to their drug loading/releasing capabilities combined with their potential photodynamic/photothermal therapeutic properties. In this review, 0-dimensional, 1-dimensional, 2-dimensional, and 3-dimensional nanomaterial-based systems are comprehensively discussed for bacterial-based diagnostic and treatment applications. Since the use of these platforms as antibacterials is relatively new, this review will provide appropriate insight into their construction and applications. As such, we hope this review will inspire researchers to explore antibacterial-based nanomaterials with the aim of developing systems for clinical applications.

Two red-emitting dicyanomethylene-4H-pyran (DM) based fluorescent probes were designed and used for peroxynitrite (ONOO- ) detection. Nevertheless, the aggregation-caused quenching effect diminished the fluorescence and restricted their further applications. To overcome this problem, tetraphenylethylene (TPE) based glycoclusters were used to self-assemble with these DM probes to obtain supramolecular water-soluble glyco-dots. This self-assembly strategy enhanced the fluorescence intensity, leading to an enhanced selectivity and activity of the resulting glyco-dot comparing to DM probes alone in PBS buffer. The glyco-dots also exhibited better results during fluorescence sensing of intracellular ONOO- than the probes alone, thereby offering scope for the development of other similar supramolecular glyco-systems for chemical biological studies.

Intercellular glycoligand-receptor interactions are implicated in a number of disease-related processes. Effective tools that target these receptors may facilitate disease theranostics. However, owing to their low binding affinity, multivalent presentation of glycoligands is needed to increase the avidity with transmembrane receptors. While previous strategies focus on the covalent coupling of glycoligands to a synthetic backbone, we show here that the use of graphene oxide (GO) greatly enhances the cellular and tissue imaging ability of a small-molecule fluorescence glycoprobe. We determine that GO with an optimum size may serve as a clustering platform to reinforce the interaction of the glycoprobe with its selective receptor on a cancer cell. This phenomenon has been consistently observed with the xenograft tissue of a tumor-bearing mouse. Using this principle we have further constructed a supramolecular glycocomposite by co-assembling the glycoprobe and an anticancer drug onto a single GO surface. In addition to imaging ability, this material displays improved toxicity for liver cancer cells that over express the glycoprotein receptor, when compared to the control cells.

Supramolecular assembly between conjugated polymers and fluorescent dyes produces a unique class of fluorogenic “nanogrenades”. These nanomaterials have shown the ability to image as well as irreversibly destruct amyloid β fibril plaques by simple light irradiation.

International audience; Glycoconjugates and their applications as lectin ligands in biology has been thoroughly investigated in the past decades. Meanwhile, the intrinsic properties of such multivalent molecules were limited essentially to their ability to bind to their receptors with high selectivity and/or avidity. The present review will focus on multivalent glycoconjugates displaying an additional capability such as fluorescence properties for applications toward imaging of cancer cells, detection of proteins or pathogens but also for drug delivery systems toward targeted cancer therapy. This review is a collection of research articles discussed in the context of the structural features of the fluorescent glycoconjugates organized according to their fluorescent core scaffold and with their representative applications.

Highly oriented Co-MOF nanoneedle arrays arein situconstructed on Co foam (Co-MOF@Co) by using a one-pot solvothermal strategy. As-prepared Co-MOF@Co can be directly served as a binder-free electrode for supercapacitor, which exhibits wonderful electrochemical performances, i.e. high specific capacitance (12783.0 mF cm-2or 1164.2 F g-1), exceptional cycling stability (90.5% retention over 10 000 cycles at 250 mA cm-2) with a loading of 10.98 mg cm-2. Meanwhile, an asymmetric supercapacitor of AC//Co-MOF@Co delivers a high ratability (87% retention upon ten-fold current density) and high energy density of 43.4 W h kg-1at the power density of 145.1 W kg-1.

In the present work, Tm3+-doped strontium phosphate glasses modified by Sn2+ are investigated. Sn2+ and Tm3+ can be co-excited with the deep UV light to emit the tunable blue light. The reinforced and purified blue emission is obtained at the excitation bands toward the deep-UV part of the spectrum. Photoluminescence emission and excitation spectra, and emission decay curves indicate consistently that the improved Tm3+ emission is in association with the presence of Sn2+ in the host glass where energy transfer from Sn2+ to Tm3+ occurs. Relevant mechanism is discussed.

In this work Er3+ doped chalcogenide glasses structurally modified by indium (In-ChG) was prepared. The mid-infrared spectroscopic properties and solubility of Er3+ in In-ChG was investigated and compared with those of gallium modified glasses (Ga-ChG). Thermal stability, mid-infrared (MIR) photoluminescence (PL), absorption spectra of both Ga-ChG and In-ChG were characterized and compared in parallel. Both the obtained MIR absorption and emission cross sections of In-ChG are higher than those of Ga-ChG. The theoretical branching ratio and decay lifetimes of 4I11/2-4I13/2 transition calculated from Judd-Ofelt theory were compared with those obtained from experiments. The tested and calculated lifetime is similar and it indicates high radiative quantum efficiency. Raman spectra reveal the fact that In-ChG possess lower phonon energy than that of Ga-ChG, which might possibly give rise to the improved MIR emission. Er3+ doped In-ChG chalcogenide glass is a potential material for MIR fiber laser application.

Tb 3+ doped SiO 2 -ZnO-BaO glasses are prepared by melting quenching method and their unique photoluminescent properties for the UV excitation are studied by using emission/excitation spectra and decay curves. Glasses in the composition (mol%) of 60SiO 2 -xZnO-(40-x)BaO-0.2Tb 3+ (x=30, 20, 10) show the strongest emission peaking at 436 nm which is different from majority of other reported work. Lower content of the free OH groups mainly contribute to this phenomenon due to the decreased probability of the multi-phonon aided non-radiative relaxation process from 5 D 3 to 5 D 4 energy levels of Tb 3+ ions. The Tb 3+ concentration also affects the 5 D 3 / 5 D 4 emissions as a result of the cross-relaxation effect on two nearby Tb 3+ ions ( 5 D 3 - 5 D 4 ⇒ 7 F 6 - 7 F 0 ). Moreover, by adjusting Tb 3+ concentration and/or ZnO/BaO concentration ratio of the host glass we obtained the adjustable emission with the required CIE chromaticity from blue to green, suggesting that the present Tb 3+ -doped SiO 2 -ZnO-BaO glasses are potential as blue/green dual-color luminescent materials for different applications.

The development of small-molecule fluorescent probes for the detection of ions and biomacromolecules and for cellular and in vivo imaging has been a very active research area. Nevertheless, many problems exist for traditional probes including their poor water solubility, toxicity and the inability to target specific tissues. Because of the enhanced water solubility, biocompatibility and targeting ability for specific cells, there has been an emerging movement to use carbohydrates as either the backbone or as a warhead to decorate conventional fluorescent probes, producing "glycoprobes" with enhanced properties. This feature article provides an overview of recently developed glycoprobes for ion and protein detection as well as targeted (receptor targeting) cellular imaging and theranostics. Here, we summarise the tactics for preparing small molecular glycoprobes and their supramolecular 2D material composites.

Correction for ‘Fluorescence imaging of a potential diagnostic biomarker for breast cancer cells using a peptide-functionalized fluorogenic 2D material’ by Wei-Tao Dou et al., Chem. Commun., 2019, 55, 13235–13238.

Protein C receptor (PROCR) is a recently discovered transmembrane biomarker for several tissue stem cells and is highly expressed in triple-negative breast cancer (TNBC) patient-derived xenografts. Herein, to enrich the toolbox for the biochemical evaluation of PROCR, we have developed a peptide-functionalized fluorogenic 2D material based on the self-assembly between a fluorescent peptide probe and thin-layer molybdenum disulfide. The material developed was suitable for the sensitive detection of PROCR recombinant protein in buffer solution and the fluorescence imaging of TNBC cells that express high levels of PROCR.

The construction of targeted and activatable materials can largely improve the precision of disease diagnosis and therapy. However, the currently developed systems either target a transmembrane antigen or are activatable to release imaging and/or therapeutic reagents intracellularly. Here we develop a simple thin-layer glycomaterial through the self-assembly between fluorescent glycoprobes, in which the carbohydrate targeting reagent and the fluorophore are linked to each other by polyethlene glycol with a suitable chain length, and thin-layer manganese dioxide. The fluorogenic material developed is both capable of targeting a transmembrane glycoprotein receptor ‘and’ fluorescently activatable by intracellular biothiols. The shell thickness of the material was determined to be important for achieving the biothiol-induced activation of fluorescence. This research might provide insight into the development of precision-enhanced self-assembled materials for disease theranostics.

We report an interlocked supramolecular ensemble formed between a conjugated polymer (CP) and a fluorescent glycoprobe for receptor-targeting cancer cell theranostics.

We have developed a theranostic nanocomposite of metallic nanoparticles that uses two distinct fluorescence mechanisms: Forster Resonance Energy Transfer (FRET) and Metal-Enhanced Fluorescence (MEF) controlled by ligand-receptor interaction. Supramolecular assembly of the fluorophore-labeled glycoligands to cyclodextrin-capped gold nanoparticles produces a nanocomposite with a quenched fluorescence due to FRET from the fluorophore to the proximal particle. Subsequently, interaction with a selective protein receptor leads to an aggregation of the composite, reactivating the fluorescence by MEF from the distal metallic particles to fluorophores encapsulated in the aggregates. The aggregation also causes a red-shift in absorbance of the composite, thereby enhancing the production of reactive oxygen species (ROS) on red-light irradiation. Our nanocomposite has proven suitable for targeted cancer cell imaging as well as multimode therapy using both the photodynamic and drug delivery properties of the composite.

Small-molecular probes capable of monitoring and interfering with the activity of biomacromolecules – such as polysaccharides, nucleotides and proteins – are of paramount importance to the advancement of life science. However, such probes that can detect and simultaneously modulate the construction of biomacromolecules are elusive. Here we report a fluorogenic, foldable glycoprobe that can recognize and assemble a protein receptor in a synchronous fashion. The glycoprobe synthesized by introducing a glycoligand (for protein recognition) to a bola-type bis-fluorophore conjugate shows a “self-shielded” fluorescence in the folded state. Association with a receptor protein rapidly unfolds the probe, releasing a fluorophore capable of crosslinking the proteins – as determined using small-angle X-ray scattering – thereby producing a unique fluorescent supramolecular construct. We have demonstrated the use of the foldable glycoprobe in order to track the endocytic cycle of a transmembrane receptor.

Industrial treatment (such as washing and rescaling) of copper-based equipment with acids requires the use of corrosion inhibitors to mitigate environmental pollution. However, the currently used organic inhibitors for copper, such as benzotriazole (BTA), are protonated in acidic solutions, thereby weakening the adsorption to a positively charged copper surface. Here we show that the use of an effective copper-ion chelator can overcome the repulsion between protonated inhibitors and a cationic copper surface in acidic solutions. With a variety of surface techniques including time of flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy and X-ray diffraction, we determine that bis-triazolyl indoleamines (BTIs) can strongly coat onto a cationic copper surface in acidic solutions through chelation with Cu(I) species. The electrochemical techniques used suggest that the BTIs are much better corrosion inhibitors than BTA, showing consistently an outstanding inhibitive efficiency in spite of the reduction of the inhibitor concentration by 100-fold and the increase of solution temperature and acidic strength. A preliminary cell viability assay suggests that our BTI is much less toxic than BTA towards two healthy cell lines.

We demonstrate the use of an effective Diels–Alder reaction to produce a library of heterocyclic, polyaromatic benzo[c]carbazole derivatives with good corrosion inhibitive potency for copper against HCl.

Here we demonstrate the simple construction and characterization of a pyrenyl glycoside-coated 2D MoS2 material composite capable of selectively capturing proteins and live cells on an electrode, as determined by differential pulse voltammetry.

Here we demonstrate that 2D MoS2 can enhance the receptor-targeting and imaging ability of a fluorophore-labelled ligand. The 2D MoS2 has an enhanced working concentration range when compared with graphene oxide, resulting in the improved imaging of both cell and tissue samples.

A new alkylation mode of fructose was developed by direct aldolization of unprotected fructose with fatty aldehydes as alkylating agents. The reaction occurs in the presence of a base in a mixture of water/EtOH at 60 °C under microwave irradiation. Trimethylamine was found the most effective base for the aldolization of fructose with short chain aldehydes (C4–C8) while better results were obtained with K2CO3 in association with tetrabutylphosphonium bromide (TBPB) for long chain aldehydes (C8–C12). The corresponding alkylated fructose were obtained as mixture of 3 main tautomers (the β-pyranoid form being the predominant isomer) and were isolated with 31–46% yield. These aldolization products were also reduced under hydrogen to give the corresponding alkylated heptaols with 84–96% isolated yields.

We have developed a supramoleuclar imaging probe based on thin-layer manganese dioxide functionalized with a fluorescent, multivalent glyco-poly-cycolodextrin for the targeted, stimulus-responsive bioimaging of cancer cells.

With this research we demonstrate that glycosylation of a naphthalimide zinc ion probe, using click chemistry, leads to an improvement of the aqueous sensitivity, working pH range and targeting ability for specific cells, together with significantly reduced cytotoxicity.

This review summarizes the recent progress in quantum dot (QD) based sensors used for the photoluminescent detection of a variety of species in vitro and in vivo. New trends in using these nanomaterials for sensing applications are highlighted.

Construction of composite materials based on the self-assembly of fluorescently labeled biomolecules with a variety of micro- or nano-quenching materials (by the Förster Resonance Energy Transfer mechanism) for the fluorogenic recognition of disease-related proteins has become a dynamic research topic in the field of fluorescence recognition. Here we summarize the recent progress on the composition of fluorescence dye-labeled biomolecules including sugars, peptides and nucleotides with organic (graphene and carbon nanotubes) and inorganic (gold nanoparticles) materials. Their application in the fluorescence detection of proteins and enzymes on both the molecular and cellular levels is discussed. Perspectives are proposed with respect to the future directions of employing these composite materials in the recognition of pathological proteins.

Recently, there has been increasing interest in the construction of graphene oxide (GO) based fluorogenic composite materials (FCMs) for the detection of ligand-protein recognitions, which modulate numerous physiological and pathological processes in nature. In the sensing systems developed, GO has been used as a platform to assemble, and thus quench the fluorescence of dye-labelled ligands for the fluorogenic (fluorescence off-on) detection of proteins through the competitive formation of ligand-protein complexes, disassembling the GO composite. Here we show that the size, structure and loading concentration of GO may largely impact the sensing performance of GO-based FCMs. We synthesized four glycodyes that incorporate diverse natural glycoligands (as recognition groups) coupled with fluorescent dyes (as both the graphene binding and signal reporting group) with different emission wavelengths for comparison with GOs with different sizes. We determined that with the increase of size, the quenching ability of GO for the glycodyes increased, whereas the GO with a moderate size showed the best sensing performance for lectins (proteins that recognize glycoligands). The plausible mechanism of action was proposed. This research suggests that judicious quality control of GO is crucial for the construction of GO-based FCMs as biosensors.

Here we show that graphene oxide greatly enhances the imaging ability of a peptide probe that selectively targets microtubules of the cytoskeleton, thus enabling the dynamic tracking of mitosis in live cells.

Rare earth doped glass materials with efficient tunable upconversion emission are a challenging field of research in the development of advanced optical devices. In this paper, tunable upconversion emission was realized by incorporating Li+ ions in Er3+/Yb3+ co-doped oxyfluoride glass ceramics containing NaYF4 nanocrystals. The prepared glass ceramics samples experience significant enhancement of luminescence intensity (up to 15 times) under 980 nm excitation. Meanwhile, a composite yellow emission with adjustable CIE chromaticity coordinates was achievable by altering the doping concentration of Li+ ions. The XRD analysis, absorption spectra and Judd-Ofelt theoretical calculations consistently revealed that these phenomena were associated with the Li+ caused shrinkage/expansion of NaYF4 crystal cells, which offers the possibility of emission tuning. The relevant luminescence mechanism was discussed in detail. Furthermore, it may pave new avenue for optimizing novel oxyfluoride glass ceramics applied in various optoelectronic fields.

We have developed a galactosyl azidonaphthalimide probe for the selective fluorogenic imaging of hepatocellular H2S, an important gaseous transmitter produced in the liver.

Extensive efforts have been devoted to the qualification of plant extracts as green corrosion inhibitors for industrial metals, but studies that demonstrate the active component(s) of these extracts remain scarce. We report here that piperine, the major pungent component of peppers, has the best corrosion inhibitive efficiency for copper in HCl among four analogous amide alkaloids isolated from a traditional Chinese medicine. This compound inhibited HCl corrosion more efficiently than cysteine, and did not exhibit markedly decreased efficiency under several harsh experimental conditions. Electrochemical and microscopic analyses suggested that piperine could form a protective layer on the metal surface via both physisorption and chemisorption, reducing the corrosion rate. The adsorption energies of all the test compounds were calculated using a hybrid density functional theory.

Effects of the crystallization treatment on visible photoluminescence properties of the Eu 2+ –Mn 2+ co-doped chalcohalide glass have been studied. A broad yellow emission at 560 nm from Mn 2+ ions is significantly enhanced by a factor of more than 25 via the controlled crystallization. X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman scattering spectroscopy studies demonstrate the precipitation of Ga 2 S 3 nano-crystals (80–100 nm) after the proper heat treatment. The effects of annealing conditions on the crystal size and photoluminescence behaviors are investigated.

Mutually enhanced Tm 3+ 1470 nm and Dy 3+ 1330 nm near-infrared (NIR) emissions are observed in Dy 3+ /Tm 3+ co-doped 70GeS 2 –10Ga 2 S 3 –20CsCl (mol%) chalcohalide glasses. With the optimized concentration of dopant ions, the NIR emission in a range from 1250 to 1550 nm shows the largest full-width-at-half-maximum (FWHM) of ~230 nm. The mechanism responsible for the mutually enhanced NIR emission is discussed. The present work demonstrates a promising way to realize superbroadband NIR emissions by rare-earth codoping.

Amine-capped γ-Fe2O3 nanoparticles were prepared by a simple one-step chemical solution method. By changing the type of iron salts, the phase composition and morphology of the samples were adjusted...

Photoluminescent properties of Eu2+/Pr3+ codoped GeS2–Ga2S3–CsCl chalcohalide glasses are investigated. The Pr3+ visible emissions are significantly enhanced with the codoping of Eu2+ under the near ultraviolet (NUV) excitation. The excitation cross-section of the Eu2+/Pr3+ codoped glass is almost three times as great as that of the Pr3+ singly doped glass. High energy transfer (ET) efficiency up to 80% from Eu2+ to Pr3+ is obtained in the codoped glasses. The dependences of emission spectra and decay curves on the concentrations of Eu2+ and Pr3+ are presented and the relevant ET mechanism is discussed.

The re-emergence of influenza raises a global concern that viral pandemics can unpredictably occur. However, effective approaches that can probe the infection risk of influenza viruses for humans are rare. In this work, we develop a glycofoldamer that can rapidly identify the glycan-receptor specificity of influenza viruses in a high-throughput manner. The coupling of glycan receptors that can be recognized by hemagglutinin (a surface protein on the virion capsid of influenza) to a fluorogenic-dye foldamer produces the glycofoldamers with minimal fluorescence in aqueous solution. After interaction with human-infecting virus strains for only five minutes, the fluorescence intensity of the glycofoldamer is remarkably enhanced with a blue-shifted emission peak. The probes have also proven effective for the rapid identification of 1) the human- or bird-infecting properties of influenza viruses in a high-throughput manner and 2) the receptor-specificity switch of a virus strain by mutations.

New C3,4-disubstituted bis-triazolyl glycoligands that feature a glucosyl or galactosyl scaffold incorporating two pyrenyl groups were synthesized via the CuI-catalyzed azide-alkyne 1,3-dipolar cycloaddition reaction (Cue-AAC). These compounds exert a major emission band corresponding to that of pyrene excimer and respond specifically to mercury with a markedly quenched fluorescence. The epimeric nature of the pyranoglycosyl scaffold is determined influential toward the selectivity of the sensors.

The corrosion inhibitive efficiency of diverse 1,2,3-triazolyl benzyl glucoside-, galactoside- and mannoside-serine/threonine conjugates readily synthesized via Cu I -catalyzed azide–alkyne cycloaddition reaction (Cue-AAC) for mild steel in HCl was examined via electrochemical impedance spectroscopy. The results indicate that these compounds are potent corrosion inhibitors even in highly concentrated HCl solutions. The potential mechanism of three inhibitors was characterized in detail via polarization and isotherm calculations. This study implies that benzyl glycoside-amino acid hybrids effectively constructed via the Cue-AAC between the highly biocompatible sugars and amino acids may represent a new class of promising and potentially green corrosion inhibitors.

Despite natural amino acids having been proposed as the green surrogate of currently used corrosion inhibitors that are generally toxic to both nature and human body during the everyday industrial processing of metallic equipments, their structural simplicity yet lowers the inhibitive potency, thereby hampering their further industrialization. We disclose here that a concise chemical ligation (CuI-catalyzed azide–alkyne 1,3-dipolar cycloaddition reaction [Cue-AAC]) between two l-amino acids that are weak or noncorrosion inhibitors may result in their largely improved protective effect for mild steel in HCl. A series of 1,4-disubstituted 1,2,3-triazolyl bis-amino acid derivatives constituted by l-serine, l-threonine, l-phenylalanine, and l-tyrosine were efficiently synthesized via Cue-AAC and deprotection reactions in high yields. Subsequently performed electrochemical impedance spectroscopy (EIS) evidenced that the inhibitive effect of these compounds for mild steel in 1 M HCl is markedly better than that...

Triazolyl bis-amino acid derivatives readily synthesized via click chemistry were identified as novel potent corrosion inhibitors for mild steel in HCl. The inhibitive characteristic of compound 4 was studied in detail via gravimetric measurement, electrochemical impedance spectroscopy, potentiodynamic polarization and scanning electron microscopy. In addition, a quantum chemical study suggests that the triazole ring involved in these inhibitors is structurally essential for the protection of metal surface.