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Supramolecular toroids have attracted continuous attention because of their fascinating topological structure and important role in biological systems. However, it still remains a great challenge to construct supramolecular functional toroids and clarify the formation mechanism. Herein, we develop a strategy to prepare supramolecular helical fluorescent nanotoroids by cooperative self-assembly of an amino acid and a dendritic amphiphile (AIE-den-1) with aggregation-induced emission characteristics. Mechanistic investigation on the basis of fluorescence and circular dichroism analyses suggests that the toroid formation can be driven by the interactions of AIE-den-1 with amino acid and goes through a topological morphology transformation from nanofibers to left-handed nanotoroids by means of a twist-fused-loop process.

Tissue engineering is a promising and revolutionary strategy to treat patients who suffer the loss or failure of an organ or tissue, with the aim to restore the dysfunctional tissues and enhance life expectancy. Supramolecular adhesive hydrogels are emerging as appealing materials for tissue engineering applications owing to their favorable attributes such as tailorable structure, inherent flexibility, excellent biocompatibility, near-physiological environment, dynamic mechanical strength, and particularly attractive self-adhesiveness. In this review, the key design principles and various supramolecular strategies to construct adhesive hydrogels are comprehensively summarized. Thereafter, the recent research progress regarding their tissue engineering applications, including primarily dermal tissue repair, muscle tissue repair, bone tissue repair, neural tissue repair, vascular tissue repair, oral tissue repair, corneal tissue repair, cardiac tissue repair, fetal membrane repair, hepatic tissue repair, and gastric tissue repair, is systematically highlighted. Finally, the scientific challenges and the remaining opportunities are underlined to show a full picture of the supramolecular adhesive hydrogels. This review is expected to offer comparative views and critical insights to inspire more advanced studies on supramolecular adhesive hydrogels and pave the way for different fields even beyond tissue engineering applications. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) This work was financially supported by the National Natural Science Foundation of China (22105131, 21671136, and 51861145311), the Guangdong Basic and Applied Basic Research Foundation (2020A1515010379), the Shenzhen Science and Technology Project Program (JCYJ20190808144413257 and JCYJ20190808145203535), the Shenzhen Key Projects of Technological Research (JSGG20200925145800001), and the International Postdoctoral Exchange Fellowship Program (PC2021046). This work is also supported by the Singapore Agency for Science, Technology and Research (A*STAR) AME IRG grant (A20E5c0081) and the Singapore National Research Foundation Investigatorship (NRF-NRFI2018-03).

Excitation functions of the natFe (p, x) 52,54Mn, 55Co, 51Cr, 52Fe, and 46Sc reactions were measured at the proton energy of 87, 94 and 100 MeV, using the stacked foil activation technique followed by the off-line γ-ray spectrometry. The experiment was carried out on the separated sector cyclotron at the Institute of Modern Physics, Chinese Academy of Sciences. The natNi (p, x)57Ni and natAl (p, x)22Na reactions with known cross sections was used to monitor the proton beam intensity. The results from this work were compared with the existing literature data available in EXFOR data library and were found to be in good agreement. TALYS-1.95 is able to reproduce, in most cases, the experimental trend. Our experimental results were also compared with evaluated nuclear data from the ENDF/B-VIII.0, JENDL-4.0/HE, and PADF-2007 libraries as a function of proton energy, which reproduced the trend of the excitation functions of the experimental natFe (p, x) reaction cross-sections. These data expand our knowledge on the related excitation functions to confirm the existing trends and to give additional experimental values on a wider energy range.

Lewis bases with strong electron delocalization can affect the chemical equilibrium of the system. Therefore, the R-NH3+ and R–C≡C–COO− prefer to coordinate with NPLs, passivating the surface defects and improving the stability of crystals.

A novel visual and fluorometric-sensor paper is prepared for the monitoring of atmospheric humidity and ethanol. The paper contains a combination of copper nanoclusters (CuNCs) and carbon dots (CDs), immobilized on a filter paper. This makes it a dual-emission system. The visual sensor shows bright fluorescence and has a diameter of ∼8 cm with uniform and homogeneous surface. The detection mechanism of the sensing paper is based on the fluorescence intensity variation of CuNCs in different environments. Desirable linear relationship is observed between fluorescence intensity ratio (red/blue) and humidity. Visible color transformation of this sensor paper is observed in the humidity range ∼40-80%, implying utility for easy and facile atmospheric humidity determination. Furthermore, due to the water and ethanol have different impacts on the spectrum, this paper-based fluorescent probe shows excellent response to ethanol. Therefore dual-emitting sensing paper, when suitably calibrated, shows promise for visual and fluorometric sensing platforms aimed at humidity or ethanol detection.

The ingenious construction of versatile cancer phototheranostic agents involving FLI, PDT, and PTT concurrently has attracted great interest. By virtue of the plentiful freely rotated moieties and the inherent twisted structure, AIEgens have been proven a perfect template for development of phototheranostic system. The systematic regulation of the energy consumption pathways through altering the molecular structure of AIEgens based on side-chain engineering is of great significance for the simultaneous pursuit of controllable fluorescence, photodynamic and photothermal properties, but has rarely been reported. Herein, an AIE-active multifunctional phototheranostic system was reported through intentional control the side-chain structure. Bearing the longest alkyl chain, all of those three energy dissipation pathways were retained controllably. In vitro and in vivo evaluations verified that TBFT2 nanoparticles performed well in terms of FLI-guided PDT and PTT synergistic cancer therapy. This study provides a new insight into the exploration of superior versatile phototheranostics through side-chain engineering.

Inspired by the excellent photothermal conversion ability and inherent nanomedicine platform property of MXenes, efficient reactive oxygen species production and prominent fluorescence emission feature of aggregation-induced emission (AIE)-active photosensitizers (PSs), as well as the extending excitation wavelength capability of upconversion nanoparticles (UCNPs), a versatile nanoplatform comprised of Ti

Controllable construction of diversiform topological morphologies through supramolecular self‐assembly on the basis of single building block is of vital importance, but still remains a big challenge. Herein, a bola‐type supra‐amphiphile, namely DAdDMA@2β‐CD, is rationally designed and successfully prepared by typical host–guest binding β‐cyclodextrin units with an aggregation‐induced emission (AIE)‐active scaffold DAdDMA. Self‐assembling investigation reveals that several morphologies of self‐assembled DAdDMA@2β‐CD including leaf‐like lamellar structure, nanoribbons, vesicles, nanofibers, helical nanofibers, and toroids, can be straightforwardly fabricated by simply manipulating the self‐assembling solvent proportioning and/or temperature. To the best of knowledge, this presented protocol probably holds the most types of self‐assembling morphology alterations using a single entity. Moreover, the developed leaf‐like lamellar structure performs well in mimicking the light‐harvesting antenna system by incorporating with a Förster resonance energy transfer acceptor, providing up to 94.2% of energy transfer efficiency., Diversiform topological morphologies including leaf‐like lamella, nanoribbons, vesicles, nanofibers, helical nanofibers, and toroids are straightforwardly realized through supramolecular self‐assembly of a novel aggregation‐induced emission (AIE)‐active supra‐amphiphile under different solvent proportioning and/or temperature. The fabricated supramolecular aggregates perform well in mimicking the light‐harvesting antenna system.

Synergistic thermo-chemotherapy based multiple stimuli-responsive drug delivery systems have achieved significant improvement of cancer curative effects compared with single modality treatment. Nevertheless, the efficacy of thermo-chemotherapy is often reduced in drug-resistant tumors and the therapy method is unexpectedly associated with potential toxicity by utilizing poorly degradable materials. Here, we report a simple approach to encapsulate three drug payloads into multi-sensitive and degradable nanospheres (SDC@NS) to achieve anticancer effects. SDC@NS comprise a photothermal agent (cypate), an anticancer agent (doxorubicin), and a nitric oxide donor (SNAP) to achieve controllable drugs release in high concentration glutathione or under near-infrared light (NIR) irradiation. Hyperthermia from NIR-mediated cypate can accelerate cancer cell apoptosis in vitro and tumor tissue ablation in vivo. Furthermore, our results also confirmed that the nitric oxide-based SDC@NS showed significant cytotoxicity compared to the nitric oxide absent group (denoted as DC@NS) and an enhanced chemotherapy effect in vivo. The photothermal effect and payloads can synchronously realize cancer therapy and provide a new insight into the enhanced synergistic therapeutic effect.

A method is described here for the quickly (

Fluorescence-based nanothermometers have potential to offer accuracy in the measurement of temperature using non-contact approaches. Herein, a C-dot/C-dot based dual-emission temperature sensing platform is fabricated through the electrostatic self-assembly of two kinds of fluorescent CDs with opposite charges. This dual-emission platform consists of several nearly-spherical CDs with two emission centers in blue (440 nm) and orange (590 nm) regions. The orange fluorescence exhibits discernible response to external temperatures in the range of ∼15 to 85 °C; on the other hand, the blue fluorescence remains nearly constant. A continuous fluorescence color change in response to temperature from orange to blue can be clearly observed by the naked eye. Thus, the as-prepared C-dot based dual-emission nanospheres can be used for optical thermometry with high reproducibility and sensitivity (0.93%/°C). Detailed characterization shows that temperature (in the 15-85 °C window) impacts the surface states of orange emissive CDs, leaving the blue emissive CDs unaffected. A model is proposed to explain the observations. Finally, by taking advantage of the excellent biocompatibility and stability, the CD based fluorescent nanothermometer is successfully used for the visual measurement of intracellular temperature variations.

The ingenious construction of versatile cancer phototheranostic agents involving FLI, PDT, and PTT concurrently has attracted great interest. By virtue of the plentiful freely rotated moieties and the inherent twisted structure, AIEgens have been proven a perfect template for development of phototheranostic system. The systematic regulation of the energy consumption pathways through altering the molecular structure of AIEgens based on side-chain engineering is of great significance for the simultaneous pursuit of controllable fluorescence, photodynamic and photothermal properties, but has rarely been reported. Herein, an AIE-active multifunctional phototheranostic system was reported through intentional control the side-chain structure. Bearing the longest alkyl chain, all of those three energy dissipation pathways were retained controllably. In vitro and in vivo evaluations verified that TBFT2 nanoparticles performed well in terms of FLI-guided PDT and PTT synergistic cancer therapy. This study provides a new insight into the exploration of superior versatile phototheranostics through side-chain engineering.

Ultra-sensitive NO 2 sensor based on hierarchical In 2 O 3 nanospheres which are successfully fabricated via facile thermal processes. Such morphology evolution is investigated by the time-dependent experiment. Remarkable features of the mesoporous structure and, large specific area (82.1 m 2 /g) and small sized nanoparticles result in the In 2 O 3 nanospheres a high NO 2 sensing efficiency. For the In 2 O 3 based NO 2 sensor, temperature of annealing process is an important factor to influence its sensing performance; the rather high sensitivity (360.1, 100 ppb) and low detection limit (1 ppb) are realized at 120 °C for the sample that annealed at 500 °C. Based on the preferable sensing performance, the novel In 2 O 3 sensor is believed to be promising to be applied for practised NO 2 detecting.

Herein, high performance of sub-ppb NO 2 sensors were fabricated based on Ag nanoparticles (NPs) decorated on hierarchical In 2 O 3 nanospheres assembled by several nanocubes subunit via a facile hydrothermal route and the subsequent decoration process. The morphology evolution of the nanospheres is investigated, which revealed that the nanocubes of the nanospheres shared the same surface and self-assembled together according to the oriented attachment mechanism. When performing as sensors, such nanostructures possessed relatively good sensitivity to NO 2 . With respect to the decoration of Ag NPs, the sensing performances can be further remarkably promoted on account of the catalyst activation and spill-over effect.

A series of dual-emission fluorescent probes was prepared from copper nanoclusters (Cu NCs) and carbon dots (CDs). They show two emission peaks (blue at 469 nm and red at 622 nm) when photoexcited at 365 nm. Upon exposure to sulfide, the Cu NCs will be deteriorated because they react with sulfide to form CuS. This results in the quenching of the red fluorescence of the Cu NCs, while the blue fluorescence of the CDs remains constant. Thus, the color of the nanocomposite changes from red to blue. The ratio of the fluorescences at the two wavelengths decreases linearly in the 2–10 ppb (26–128 nM) sulfide concentration range, and the limit of detection is 0.33 ppb (4.3 nM). The nanocomposite also was placed in an agar gel and then incorporated into a paper strip for fluorometric monitoring of gaseous hydrogen sulfide.

Fluorometric “turn-on” glucose detection is presented that is based on the Fenton reaction which can trigger the generation of Ag nanoclusters (Ag NCs). Oxidation of D-glucose by glucose oxidase generates H2O2. Reactive radicals are formed from the Fenton reaction of H2O2 and Fe2+. These radicals initiate the polymerization of methacrylic acid to form poly(methacrylic acid) which is used as a template to generate fluorescent Ag NCs in situ by illumination with UV light. The increase in Ag NCs fluorescence intensity can be used to quantify glucose concentration. The sensing approach employed here provides a new strategy for the determination of glucose selectively.

The profiling of bacterial metabolism is of great significance in practical applications. Therefore, the development of ultrasensitive and highly selective probe for bacterial metabolism detection and imaging is extremely desirable. Herein, a novel dual-emission pH-response bacterial metabolism detection and imaging probe is successfully developed. This probe consists of large-sized and easily separated SiO2 microspheres, copper nanoclusters (Cu NCs) with red emission, and carbon dots (CDs) with blue emission through in-situ self-assembly. In this system, the fluorescence of Cu NCs is sensitive to pH change due to their obvious aggregation-induced emission enhancement (AIEE) property, while the blue fluorescence of CDs remained almost stable. Therefore, red fluorescence and blue fluorescence are compounded with different fluorescence intensity at different pH values, and their fluorescence ratio is also different. By observation of composite fluorescence color, the visual colorimetric pH detection can be realized with the change of pH value of 0.2 units. Utilizing this system, we are able to detect bacterial metabolism with high signal-to-noise ratio, and it can also be used for bacterial metabolic imaging. Therefore, the pH-responsive Cu NCs-based dual-emission ratiometric fluorescent probe we constructed can provide new ideas for bacterial detection, antimicrobial sterilization, and biological imaging.

A series of dual-emission fluorescent probes was prepared from copper nanoclusters (Cu NCs) and carbon dots (CDs). They show two emission peaks (blue at 469 nm and red at 622 nm) when photoexcited at 365 nm. Upon exposure to sulfide, the Cu NCs will be deteriorated because they react with sulfide to form CuS. This results in the quenching of the red fluorescence of the Cu NCs, while the blue fluorescence of the CDs remains constant. Thus, the color of the nanocomposite changes from red to blue. The ratio of the fluorescences at the two wavelengths decreases linearly in the 2-10 ppb (26-128 nM) sulfide concentration range, and the limit of detection is 0.33 ppb (4.3 nM). The nanocomposite also was placed in an agar gel and then incorporated into a paper strip for fluorometric monitoring of gaseous hydrogen sulfide. Graphical abstract Schematic presentation of the synthesis of Cu NCs (copper nanoclusters)-CDs (carbon dots) dual-emission nano-assembly, Cu NCs-CDs-agar fluorescent film and their application for the detection of sulfide and H

The profiling of disease-related biomarkers is an essential procedure for the accurate diagnosis and intervention of metabolic disorders. Therefore, the development of ultrasensitive and highly selective fluorogenic biosensors for diverse biomarkers is extremely desirable. There is still a considerable challenge to prepare nanocluster-based fluorescence turn-on probes capable of recognizing multiple biomolecules. We herein provide a novel nanocluster-based chemical information processing system (CIPS) for the programmable detection of various metabolites and enzymes. This CIPS consists of biocatalytic reactions between substrates and their respective oxidases to generate H2O2, which was then employed to synthesize bright fluorescent silver nanoclusters (Ag NCs). Utilizing this system, we are able to accurately probe a series of substrates/corresponding oxidases with high sensitivity and specificity, including glucose/glucose oxidase, uric acid/uric acid oxidase, sarcosine/sarcosine oxidase, choline/cholin...

A fast, sensitive, and convenient dual-emission water detector was robustly fabricated. This detector was prepared with blue fluorescent carbon dots (CDs) and red fluorescent Cu nanoclusters (NCs), and showed two well-resolved and intensity-comparable fluorescence peaks under a single excitation wavelength. Moreover, it showed strong red fluorescence in organic solvent due to the aggregation-induced emission enhancement (AIEE) properties of the Cu NCs, but the red fluorescence was gradually quenched with an increasing amount of water, whereas the blue fluorescence remained constant. The differences in response result in a continuous fluorescence color change from red to blue that can be clearly observed by the naked eye. Thus, as-prepared Cu NC-based dual-emission nanomaterials can be used for ratiometric fluorescence detection of trace amounts of water in organic solvents by taking advantage of the water sensitivity of their fluorescence intensity ratios (red/blue) and their low detect limits (

In the present work the erosion behavior on the surface of GaN epi-layer by the impact of various slow highly charged heavy ions (SHCIs, including Arq+. Xeq+ and Pbq+, in two incidence geometries) was investigated. Atomic force microscopy reveals a well-defined threshold of potential energy carried by the incident heavy ions accounting for the surface erosion. This threshold also depends on the projected range of the SHCIs, the longer the projected range, the higher the potential energy required for the onset of surface erosion. And the etched depth is close to a linear function of potential energy deposited, increasing with the potential energy increases. Moreover, the etching rate for 60 degrees off normal incidence is by more than a factor of 2 larger than etching rate for normal incidence, and the etch rate by Xeq+ is larger than by Pbq+ under the same potential energy and incident direction. And a mechanism is discussed. (C) 2010 Elsevier B.V. All rights reserved.