Shape Transformation of Light-Responsive Pyrene-Containing Micelles and Their Influence on Cytoviability

The amphiphilic pyrene-containing random copolymers with light-responsive pyrene ester bonds were synthesized by copolymerizing 1-pyrenemethyl acrylate (PA) and <i>N</i>,<i>N</i>-dimethylacrylamide (DMA). The P­(DMA-<i>co</i>-PA) copolymers formed spherical micelles in water, which were transformed into nanorods as a result of cleavage of the pyrene ester bonds under UV irradiation. In vitro culture with A549 cells and Raw cells showed that compared to the nonphotodegradable ones, the photodegradable P­(DMA-<i>co</i>-PA) micelles caused significantly higher cytotoxicity under the same UV irradiation. The intracellular reactive oxygen species (ROS) level had a positive correlation with the cytotoxicity regardless of the cell types. The nonphotodegradable pyrene-containing micelles produced a lower level of ROS under UV irradiation. However, the photodecomposable P­(DMA-<i>co</i>-PA) micelles produced a significant higher level of ROS under the same trigger of UV irradiation, which caused the shape transformation of micelles to nanorods and higher cytotoxicity simultaneously

Enhanced Cellular Uptake of Bowl-like Microcapsules

Among several properties of colloidal particles, shape is emerging as an important parameter for tailoring the interactions between particles and cells. In this study, bowl-like multilayer microcapsules were prepared by osmotic-induced invagination of their spherical counterparts in a concentrated polyelectrolyte solution. The internalization behaviors of bowl-like and spherical microcapsules were compared by coincubation with smooth muscle cells (SMCs) and macrophages. The bowl-like capsules tended to attach onto the cell membranes from the bend side and could be enwrapped by the membranes of SMCs, leading to a faster uptake rate and larger accumulation inside cells than those of their spherical counterparts. These results are important for understanding the shape-dependent internalization behavior, providing useful guidance for further materials design especially in biomedical applications

Stilbene Derivatives from Photorhabdus temperata SN259 and Their Antifungal Activities against Phytopathogenic Fungi

Chemical investigation of an insect pathogenic enterobacterium, Photorhabdus temperata SN259, led to the isolation and identification of seven metabolites, which include three new compounds, 3-hydroxy-2-isopropyl-5-phenethylphenyl carbamate, <b>1</b>, 2-(1-hydroxypropan-2-yl)-5-[2-phenylethyl]­benzene-1,3-diol, <b>2</b>, 2-(1-hydroxypropan-2-yl)-5-[(<i>E</i>)-2-phenylethenyl]­benzene-1,3-diol, <b>3</b>, and four known metabolites (<b>4</b>–<b>7</b>). Their structures were elucidated on the basis of MS and NMR data and by comparison with those reported previously. The activities of compounds <b>1</b>–<b>7</b> were evaluated against four phytopathogenic fungi (Pythium aphanidermatum, Rhizoctonia solani Kuhn, Exserohilum turcicum, and Fusarium oxysporum). In an agar medium assay, compounds <b>1</b> and <b>7</b> showed strong inhibition against P.  aphanidermatum with EC₅₀ values of 2.8 and 2.7 μg/mL, respectively. By comparing the structure of compounds <b>1</b>–<b>7</b>, we deduced that the acylamino group in compound <b>1</b> and the isopropyl group in compound <b>7</b> contribute to the inhibitory activity

Design, Synthesis, and Insecticidal Activity of Novel Isoxazoline Diacylhydrazine Compounds as GABA Receptor Inhibitors

A series of isoxazoline derivatives containing diacylhydrazine moieties were designed and synthesized as potential insecticides. Most of these derivatives exhibited good insecticidal activities against Plutella xylostella, and some compounds exhibited excellent insecticidal activities against Spodoptera frugiperda. Especially, D14 showed outstanding insecticidal activity against P. xylostella (LC50 = 0.37 μg/mL), which was superior to that of ethiprole (LC50 = 2.84 μg/mL) and tebufenozide (LC50 = 15.3 μg/mL) and similar to that of fluxametamide (LC50 = 0.30 μg/mL). Remarkably, the insecticidal activity of D14 against S. frugiperda (LC50 = 1.72 μg/mL) was superior to that of chlorantraniliprole (LC50 = 3.64 μg/mL) and tebufenozide (LC50 = 60.5 μg/mL) but lower than that of fluxametamide (LC50 = 0.14 μg/mL). The results of electrophysiological experiments, molecular docking, and proteomics experiments indicate that compound D14 acts by interfering with the γ-aminobutyric acid receptor to control pests

Design, Synthesis, and Insecticidal Activity of Novel Isoxazoline Diacylhydrazine Compounds as GABA Receptor Inhibitors

A series of isoxazoline derivatives containing diacylhydrazine moieties were designed and synthesized as potential insecticides. Most of these derivatives exhibited good insecticidal activities against Plutella xylostella, and some compounds exhibited excellent insecticidal activities against Spodoptera frugiperda. Especially, D14 showed outstanding insecticidal activity against P. xylostella (LC50 = 0.37 μg/mL), which was superior to that of ethiprole (LC50 = 2.84 μg/mL) and tebufenozide (LC50 = 15.3 μg/mL) and similar to that of fluxametamide (LC50 = 0.30 μg/mL). Remarkably, the insecticidal activity of D14 against S. frugiperda (LC50 = 1.72 μg/mL) was superior to that of chlorantraniliprole (LC50 = 3.64 μg/mL) and tebufenozide (LC50 = 60.5 μg/mL) but lower than that of fluxametamide (LC50 = 0.14 μg/mL). The results of electrophysiological experiments, molecular docking, and proteomics experiments indicate that compound D14 acts by interfering with the γ-aminobutyric acid receptor to control pests

Phototriggered N₂‑Generating Submicron Particles for Selective Killing of Cancer Cells

Killing of cancer cells by applying mechanical disruption has been an appealing emerging strategy for cancer treatment in recent years. In this study, photoresponsive submicron particles based on diazo-resin that are able to release N₂ under UV irradiation were prepared through a polyamine–salt aggregation method. After surface modification with hyaluronic acid, the particles could be internalized selectively by cancer cells and were mainly located in lysosomes after 6 h incubation. The viability of cancer cells decreased obviously after they were co-cultured with photoresponsive particles and UV irradiation due to the integrity damage of lysosomes by phototriggered N₂ generation and the subsequent increased number of reactive oxygen species

Scalable Synthesis of Defect Abundant Si Nanorods for High-Performance Li-Ion Battery Anodes

Microsized nanostructured silicon–carbon composite is a promising anode material for high energy Li-ion batteries. However, large-scale synthesis of high-performance nano-Si materials at a low cost still remains a significant challenge. We report a scalable low cost method to synthesize Al/Na-doped and defect-abundant Si nanorods that have excellent electrochemical performance with high first-cycle Coulombic efficiency (90%). The unique Si nanorods are synthesized by acid etching the refined and rapidly solidified eutectic Al–Si ingot. To maintain the high electronic conductivity, a thin layer of carbon is then coated on the Si nanorods by carbonization of self-polymerized polydopamine (PDA) at 800 °C. The carbon coated Si nanorods (Si@C) electrode at 0.9 mg cm^–2 loading (corresponding to area-specific-capacity of ∼2.0 mAh cm^–2) exhibits a reversible capacity of ∼2200 mAh g^–1 at 100 mA g^–1 current, and maintains ∼700 mAh g^–1 over 1000 cycles at 1000 mA g^–1 with a capacity decay rate of 0.02% per cycle. High Coulombic efficiencies of 87% in the first cycle and ∼99.7% after 5 cycles are achieved due to the formation of an artificial Al₂O₃ solid electrolyte interphase (SEI) on the Si surface, and the low surface area (31 m² g^–1), which has never been reported before for nano-Si anodes. The excellent electrochemical performance results from the massive defects (twins, stacking faults, dislocations) and Al/Na doping in Si nanorods induced by rapid solidification and Na salt modifications; this greatly enhances the robustness of Si from the volume changes and alleviates the mechanical stress/strain of the Si nanorods during the lithium insertion/extraction process. Introducing massive defects and Al/Na doping in eutectic Si nanorods for Li-ion battery anodes is unexplored territory. We venture this uncharted territory to commercialize this nanostructured Si anode for the next generation of Li-ion batteries

High-Sensitivity Microchannel-Structured Collagen Fiber-Based Sensors with Antibacterial and Hydrophobic Properties

Wearable sensors have become significant for collecting motion and health information. It is urgent to develop high-sensitivity sensors that can be used in various complex environments. Herein, we prepare an antibacterial and superhydrophobic 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS)-cross-linked collagen fibers/MXene/Ag nanoparticles (FCMA) aerogel sensor. Benefiting from the microchannel structure of the FCMA aerogel, the sensor achieved high sensitivity (168.44 kPa–1) and fast response (0.2 s) and recovery (0.1 s). Meanwhile, the sensor can stably detect tiny physiological signals and large movements of human body. Importantly, owing to the low surface energy of FAS, the FCMA aerogel shows superhydrophobic and antifouling properties for application in damp or rainy conditions. The antiadhesion of superhydrophobic surface and the bactericidal effects of Ag nanoparticles make the sensor possess good antibacterial and antifungal activities, which can effectively prevent bacterial/fungi growth and protect human health. Therefore, the flexible and multifunctional FCMA aerogel sensor has versatile and promising applications in wide areas

High-Sensitivity Microchannel-Structured Collagen Fiber-Based Sensors with Antibacterial and Hydrophobic Properties

Wearable sensors have become significant for collecting motion and health information. It is urgent to develop high-sensitivity sensors that can be used in various complex environments. Herein, we prepare an antibacterial and superhydrophobic 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS)-cross-linked collagen fibers/MXene/Ag nanoparticles (FCMA) aerogel sensor. Benefiting from the microchannel structure of the FCMA aerogel, the sensor achieved high sensitivity (168.44 kPa–1) and fast response (0.2 s) and recovery (0.1 s). Meanwhile, the sensor can stably detect tiny physiological signals and large movements of human body. Importantly, owing to the low surface energy of FAS, the FCMA aerogel shows superhydrophobic and antifouling properties for application in damp or rainy conditions. The antiadhesion of superhydrophobic surface and the bactericidal effects of Ag nanoparticles make the sensor possess good antibacterial and antifungal activities, which can effectively prevent bacterial/fungi growth and protect human health. Therefore, the flexible and multifunctional FCMA aerogel sensor has versatile and promising applications in wide areas

High-Sensitivity Microchannel-Structured Collagen Fiber-Based Sensors with Antibacterial and Hydrophobic Properties

Wearable sensors have become significant for collecting motion and health information. It is urgent to develop high-sensitivity sensors that can be used in various complex environments. Herein, we prepare an antibacterial and superhydrophobic 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS)-cross-linked collagen fibers/MXene/Ag nanoparticles (FCMA) aerogel sensor. Benefiting from the microchannel structure of the FCMA aerogel, the sensor achieved high sensitivity (168.44 kPa–1) and fast response (0.2 s) and recovery (0.1 s). Meanwhile, the sensor can stably detect tiny physiological signals and large movements of human body. Importantly, owing to the low surface energy of FAS, the FCMA aerogel shows superhydrophobic and antifouling properties for application in damp or rainy conditions. The antiadhesion of superhydrophobic surface and the bactericidal effects of Ag nanoparticles make the sensor possess good antibacterial and antifungal activities, which can effectively prevent bacterial/fungi growth and protect human health. Therefore, the flexible and multifunctional FCMA aerogel sensor has versatile and promising applications in wide areas