Precise Regulation Strategy for Fluorescence Wavelength of Aggregation-Induced Emission Carbon Dots.

Aggregation-induced emission (AIE) carbon dot (CDs) in solid state with tunable multicolor emissions have sparked significant interest in multidimensional anti-counterfeiting. However, the realization of solid-state fluorescence (SSF) by AIE effect and the regulation of fluorescence wavelength in solid state is a great challenge. In order to solve this dilemma, the AIE method to prepare multi-color solid-state CDs with fluorescence wavelengths ranging from bright blue to red emission is employed.

Double layered asymmetrical hydrogels enhanced by thermosensitive microgels for high-performance mechanosensors and actuators.

Thermosensitive hydrogels have found extensive applications in soft devices, but they often suffer from limited functionalities, low response rate and small response amplitude. In this work, double layered asymmetrical hydrogels composed of a thermosensitive layer and a non-thermosensitive layer are developed to simultaneously achieve high-performance mechanosensing and actuating properties in a single hydrogel. In thermosensitive layer, thermosensitive microgels are introduced to construct hierarchical structure, which accounts for the enhanced thermosensitive behaviors by cooperative responsiveness.

Stable Flexible Electronic Devices under Harsh Conditions Enabled by Double-Network Hydrogels Containing Binary Cations.

Hydrogels are increasingly used in flexible electronic devices, but the mechanical and electrochemical stabilities of hydrogel devices are often limited under specific harsh conditions. Herein, chemically/physically cross-linked double-network (DN) hydrogels containing binary cations Zn and Li are constructed in order to address the above challenges. Double networks of chemically cross-linked polyacrylamide (PAM) and physically cross-linked κ-Carrageenan (κ-CG) are designed to account for the mechanical robustness while binary cations endow the hydrogels with excellent ionic conductivity and outstanding environmental adaptability.

Regenerable and Highly Stable Two-Dimensional Imine-Based Covalent Organic Framework for Simultaneous Rapid Detection and Adsorption of Cu Ions.

The development of efficient fluorescent probes and adsorbents for detecting and removing Cu, which pose potential environmental and health risks, is a highly active area of research. However, achieving simultaneously improved fluorescence detection efficiency and enhanced adsorption capacity in a single porous probe remains a significant challenge. In this study, we successfully synthesized a two-dimensional imine-based TAP-COF using 2,4,6-triformylphloroglucinol and tri(4-aminophenyl)amine as raw materials.

Visual detection of water content in liquor with near-infrared fluorescence sensor assisted by smartphone.

Water content was an essential indicator in organic solvents, and it was necessary to develop a facile, cheap and readily available tool for the real-time, specifical and sensitive detection of water content. In this work, two novel D-π-A type near-infrared fluorescence sensors (DCM-1 and DCM-2) were designed and synthesized for the detection of trace water in organic solvents. DCM-1 and DCM-2 with solvent-dependent effects and large Stokes shift (>120 nm) showed good linear "intensity-to-content" relationships in four commonly-used organic solvents, and accomplished the ultra-fast and high-accuracy detection of the trace water in organic solvents.

Facile preparation strategy of novel BO-modified carbon dots with 1.99 s ultra-long Room-Temperature phosphorescence for multidimensional encryption.

Facile synthesis of Ultralong room-temperature phosphorescence (URTP) with super stability and long-afterglow are of great significance, but hard to achieve. Herein, a brilliant gram-scale and solvent-free pyrolysis treatment strategy has been developed to prepare high-performance URTP carbon dots (CDs) by regulating different temperature (250-500 °C). The optimized CDs (CD-400) showed room-temperature phosphorescence 1.

An ESIPT-Based Fluorescent Probe for Aqueous Cu Detection through Strip, Nanofiber and Living Cells.

Constructed on the benzothiazole-oxanthracene structure, a fluorescent probe RBg for Cu was designed under the ESIPT mechanism and synthesized by incorporating amide bonds as the connecting group and glyoxal as the identifying group. Optical properties revealed a good sensitivity and a good linear relationship of the probe RBg with Cu in the concentration range of [Cu] = 0-5.0 μmol L.

A PET Fluorescent Probe for Dynamic Pd Tracking with Imaging Applications in the Nanofiber and Living Cells.

Constructed on the moiety of a lactam screw ring, a near-infrared fluorescent probe RCya for Pd was designed under the PET mechanism and synthesized by incorporating 2,4-dihydroxybenzaldehyde as the recognition group. Dynamic detection of aqueous Pd by the probe RCya could be accomplished through ion competition, linear response, fluorescence-pH/time stabilities, and other optical tests. Moreover, the high selectivity, low cytotoxicity, cell permeability, and lysosome accumulation properties of RCya enabled the imaging applications on solid-state RCya-PAN composite nanofibers and in living cells.

High sensitivity for detecting trace Sn in canned food using novel covalent organic frameworks.

Tin (Sn) element plays a vital role in the human body, and its detection is a mandatory inspection item for canned food. The application of covalent organic frameworks (COFs) in fluorescence detection has received extensive attentions. In this work, we designed a kind of novel COFs (COF-ETTA-DMTA) with high specific surface area (353.

A Highly Sensitive and Selective Fluorescein-Based Cu Probe and Its Bioimaging in Cell.

Copper is a vital trace metal in human body, which plays the significant roles in amounts of physiological and pathological processes. The application of copper-selective probe has attracted great interests from environmental tests to life process research, yet a few of sensitive Cu tests based on on-site analysis have been reported. In this paper, a novel fluorescein-based fluorescent probe N4 was designed, synthesized, and characterized, which exhibited high selectivity and sensitivity to Cu comparing with other metal ions in ethanol-water (1/1, v/v) solution.

Electrospun Elastic Films Containing AgNW-Bridged MXene Networks as Capacitive Electronic Skins.

Electronic skins (e-skins) are increasingly investigated and applied in wearable devices, but the robustness and convenient production of traditional e-skins are restricted. In this work, electrospun sandwich-structured elastic films (ESEFs) are developed and utilized as capacitive e-skins. The ESEFs consist of two nanocomposite mats as the electrode layers and a sandwiched thermoplastic polyurethane (TPU) mat as the dielectric layer.

Rational construction of deep-red fluorescent probe for rapid detection of HClO and its application in bioimaging and paper-based sensing.

Hypochlorous acid (HClO), the core bactericidal substance of the human immune system, plays a vital role in many physiological and pathological processes in the human body. In this work, we designed and synthesized a novel deep-red fluorescent probe TCF-ClO for the determination of hypochlorous acid through theoretical analysis. The results showed that probe TCF-ClO exhibited excellent characteristics of long-wavelength emission (635 nm), fast response (< 1 min), and low detection limit (24 nM).

Fabrication of carbon dots for sequential on-off-on determination of Fe and S in solid-phase sensing and anti-counterfeit printing.

Glutathione and 2-aminopyridine are used as carbon sources to prepare carbon dots (CDs) by a one-step hydrothermal reaction. The results show that the average particle diameter of CDs is 8.64 nm with uniform size distribution and the fluorescence quantum yield is 13.

Green synthesis of orange emissive carbon dots for the detection of Agand their application via solid-phase sensing and security ink.

Fluorescent carbon dots (CDs) have attracted considerable interest due to their superior optical properties and facile preparation. In this work, O-phenylenediamine and melamine were used as precursors for the one-step hydrothermal synthesis of novel orange emissive CDs (O-CDs) in an aqueous solution. The fluorescence intensity (580 nm) of the O-CDs exhibited a good linear relationship with Agin the range of 0.

Mussel-inspired self-adhesive hydrogels by conducting free radical polymerization in both aqueous phase and micelle phase and their applications in flexible sensors.

Polydopamine (PDA)-based self-adhesive hydrogel sensors are extensively explored but it is still a challenge to construct PDA-based hydrogels by free radical polymerization. Herein, a new approach to construct self-adhesive hydrogels by conducting free radical polymerization in both aqueous phase and micelle phase is developed. The following two-phase polymerization processes account for the formation of the self-adhesive hydrogels.

Detection of Cu and S with fluorescent polymer nanoparticles and bioimaging in HeLa cells.

Novel spherical polymer nanoparticles were synthesized by hyperbranched polyethylenimine (hPEI) and 6-hydroxy-2-naphthaldehyde (HNA) via Schiff base reaction (one-pot reaction), which had great advantages in water solubility and green synthesis. Meanwhile, probe PEI-HNA could quickly detect Cu in the range of 0-60 μM in 30 s with the detection limit of 243 nM. The fluorescence of PEI-HNA-Cu could be recovered by the addition of S in 50 s with the detection limit of 227 nM.

Construction of DCM-based NIR fluorescent probe for visualization detection of HS in solution and nanofibrous film.

Hydrogen sulfide (HS) played crucial roles in biological processes and daily life, and the abnormal level of HS was associated with many physiological processes. In this paper, we designed and developed a dicyanomethylene-4H-chromene (DCM)-based near-infrared (NIR) fluorescent probe DCM-NO guided by theoretical calculation. The probe displayed excellent selectivity towards HS with a fast response time (3 min) and low detection limit (fluorescence 25.

Capacitive Pressure Sensors Containing Reliefs on Solution-Processable Hydrogel Electrodes.

Highly sensitive capacitive-type pressure sensor has been achieved by fabricating reliefs on solution-processable hydrogel electrodes. Hybrid PVA/PANI hydrogels (PVA, poly(vinyl alcohol); PANI, polyaniline) with a fully physically cross-linked binary network are selected as the electrodes of the pressure sensors. On the basis of the solution processability, reliefs are fabricated on the surface of PVA/PANI hydrogel electrodes by a template method.

Fluorescent sensing film decorated with ratiometric probe for visual and recyclable monitoring of Cu.

Specifically, visually, and quantitatively monitor copper ion (Cu) is critical in the area of biological and environmental detection. Herein, a ratiometric fluorescent probe with benzoxazole appended xanthenes skeleton was constructed and further employed to monitor Cu in Hela cells, real water samples, and test strips. An easily distinguishable colorimetric (colorless to red) and fluorescence (green to red) change could be observed by naked eye under the portable UV lamp (365 nm) and the changes could be recovered by adding S.

Oxidized nanoscale zero-valent iron changed the bioaccumulation and distribution of chromium in zebrafish.

Influences of colloidal stabilities of nanoparticles (NPs) on the bioaccumulation of co-existing pollutants remains largely unknown. In this study, two oxidation products of nanoscale zero-valent iron (nZVI) with totally varied colloidal stabilities, termed highly oxidized nZVI (HO-nZVI) and lowly oxidized nZVI (LO-nZVI), were exposed to zebrafish with chromium (Cr); this approach was used to investigate the impacts of colloidal stability of oxidized nZVI on the bioaccumulation of Cr in zebrafish. A significant increase in the Cr and NP content in the viscera of fish in the presence of the oxidized nZVI after 20 days of exposure was confirmed, which indicated that Cr was consumed by fish through the uptake of the NPs.

Predicting the aggregation tendency of oxidized nanoscale zero-valent iron in aquatic environments.

Predicting the aggregation tendency of nanoscale zero-valent iron (nZVI), oxidized nZVI, in particular, is crucial for the risk assessment of nZVI in aquatic environments. In this study, the comprehensive effects of the pH and ionic strength (IS) on the aggregation behaviors of two highly oxidized nZVIs (HO-nZVI) were examined. Compared with hematite nanoparticles, HO-nZVI presented a sudden acceleration in aggregation under critical conditions; moreover, the morphology of the HO-nZVI aggregates at pH and IS values higher or lower than the critical conditions was significantly different.

Rhodol-based fluorescent probes for the detection of fluoride ion and its application in water, tea and live animal imaging.

Herein, we presented two novel turn-on colorimetric and fluorescent probes based on a F triggered SiO bond cleavage reaction, which displayed several desired properties for the quantitative detection for F, such as high specificity, rapid response time (within 3 min) and naked-eye visualization. The fluorescence intensity at 574 nm (absorbance at 544 nm) of the solution was found to increase linearly with the concentration of F (0.00-30.

Highly Stretchable, Fatigue-Resistant, Electrically Conductive, and Temperature-Tolerant Ionogels for High-Performance Flexible Sensors.

Ionogels are ideal candidate materials for flexible sensors, but their stretchability and fatigue resistance are limited. Herein, highly stretchable, fatigue-resistant, electrically conductive, and temperature-tolerant ionogels are investigated and further applied in fabricating high-performance flexible sensors. The ionogels consist of a poly(acrylic acid) (PAA) network and a commonly used room-temperature ionic liquid (RTIL) named 1-ethyl-3-methylimidazolium dicyanamide ([EMIm][DCA]).

Near-infrared fluorescent probe for selective detection of HS and its application in living animals.

In this study, a novel near-infrared fluorescent off-on probe for HS based on seminaphthorhodafluor fluorophore is designed and constructed, which could be used in detection with 121-fold (23-fold) fluorescent (absorbance) enhancement at 630 nm (572 nm), fast responsiveness (completed within 5 min), high sensitivity, and lower cellular autofluorescence interference. Based on these excellent optical properties, the probe was employed to monitor HS in red wine samples with satisfactory results. Moreover, the probe was successfully applied for monitoring and imaging HS quantitatively in Hela cells and live athymic nude mice, indicating its potential application in biological science.

Dual-functional probe based on rhodamine for sequential Cu and ATP detection in vivo.

A rhodamine-based fluorescent probe for Cu and ATP has been designed. The fluorescence intensity/absorbance was significantly enhanced upon the addition of Cu owning to the opening of the spiro-ring of rhodamine, which quickly returned to the original level due to the reconstruction of the probe by the reacting with ATP. Cu/ATP-induced fluorescent intensity/aborbance changes showed a good linear relationship with the concentration of Cu/ATP in the range of 2-20 μM/0-10 μM with a detection limit of 0.