Latest ArticlesIn order to advance the commercialization of rechargeable Li-air batteries, it is of importance to explore cathode catalyst with efficient catalytic activity. Transition metal oxides have poor electrical conductivity, while cobalt phosphide has excellent electrical conductivity and large specific surface area. Nevertheless, its application in organic Li-air batteries has been much less studied, and the electrocatalytic activity desires to be further elevated. Here, CoP/Co2P heterojunction composite with higher polarity was fabricated. The discharge product of high-polarity CoP/Co2P had a new porous box-like morphology, which was easy to be decomposed and exposed more active sites. The highly polar CoP/Co2P heterostructure composite had homogeneous pores, the synergistic effect existed between CoP and Co2P, and the discharge product was porous box mixed with Li2O2 and LiOH, which made CoP/Co2P achieve high specific capacity of 14632 mAh/g and cycle stably 161 times when used as air electrode cathode catalyst. This work furnished a thought for the construction of cathode catalysts with efficient catalytic activity for Li-air batteries.
Nowadays, due to excellent biological and polymeric characteristics, DNA has been widely noted as an emerging building block to construct diverse materials for biosensing, in vivo imaging, drug delivery, and disease therapy. Particularly, relying on programmability, predictability, and stability of DNA, DNA walkers have opened new and exciting opportunities in modern life sciences for target detection and biological analysis, which are constructed by self-assembly of DNA or combining DNA with other nanomaterials (e.g., quantum dots, gold nanoparticles, magnetic nanoparticles, polymers). Compared with conventional nanomaterials (lanthanide-doped upconversion nanoparticles, magnetic nanomaterials, carbon dots, silicon dots, and so on), DNA walkers showed convenient modification, lower biotoxicity, excellent biocompatibility and high biostability, improving the biological application. Meanwhile, with high-speed operating efficiency and sustainable operation, DNA walkers powered by strand displacement reaction or protein enzyme/DNAzyme reaction, have highly sensitive detection and signal amplification abilities, which are applied in biosensing, material assembly and synthesis, and early cancer diagnosis. Worthily, DNA walkers could be regarded as signal amplifiers, which enhanced the signal transduction and amplified biosensor sensing signals. Herein, we systematically and comprehensively summarized the operating principles of various DNA walkers, categorized rational design of the DNA walker, and outlined the application of DNA walker in biosensors. Furthermore, the challenges and future trends of DNA walkers were discussed.
Lung cancer is one of the most common malignant tumors with the fastest increase in the incidence rate and mortality. Even after maximum tumor resection assistance with a radiotherapy and chemotherapy combination, the recurrence of non-small cell lung cancer is still inevitable. In addition, low targeting efficiency and poor permeability of drug delivery systems strongly affect the therapeutic efficiency of anti-cancer drugs on non-small cell lung cancer. Here we designed a gemcitabine (GEM) loaded arginine-glycine-aspartic acid-cysteine (RGDc)-modified gold mineralization "hybrid nanozyme bomb" (RGTG) to overcome those obstacles. RGDc modification improved the active targeting of liposomes to the tumor tissues with the second near-infrared (NIR-II)-triggered gold-shell disruption and GEM release. The collapsed gold-shell particles with a smaller size could penetrate the tumor solid barrier and act as photothermal therapy (PTT) agents to improve PTT therapy and starvation therapy via generating gluconic acid and reactive oxygen species (ROS). Moreover, the resting reversal effect of gold particles on tumor fibroblasts can achieve accelerating tumor penetration of gold particles and GEM. Compared to monotherapy, RGTG showed significant improvement in tumor inhibition, with a tumor volume reduction of 83% compared to the control group, which provides a promising tumor treatment platform for non-small cell lung cancer (NSCLC).
Structural colors originated from Mie scattering of dielectric spheres can be regulated by the coupling effect between them and substrates. Here a rapid visual identification method of silver ornaments was proposed by the coupling effect of ZnO spheres with them. Both simulation and experimental results proved that, by coupling with different metal substrates, the Mie resonance scattering peaks of ZnO spheres with dimeter of 700 nm showed different degrees of redshift, which lead to different structural color appeared when ZnO spheres deposited on different metal surfaces with a similar appearance. A red structural color was displayed on the surface of the real silver ornament and a yellow-green structural color was shown on the surface of the cupronickel ornament. This method is quite simple and low-cost because it only needs to spray the dispersion of ZnO spheres on the ornament surface. Due to the mild chemical properties of the ZnO, covering and erasing ZnO spheres on the surface of silver would not corrode the silver ornament. Finally, an atomizer method was used for portable and daily testing. This work opens new perspectives on the visual identification of silver.
Norovirus is an infectious disease that can cause non-bacterial gastroenteritis, which has a low infectious dose, rapid onset, and strong transmission ability; therefore, rapid and sensitive detection is essential to reduce the transmission of gastroenteritis. In the study, a norovirus GII loop-mediated isothermal amplification assay was developed and prepared into freeze-drying microspheres, and a closed-cassette-based, integrated, reagent-ambient storage, on-site instant detection platform for norovirus GII was constructed using a commercial, fully automated nucleic acid analyzer with integrated magnetic bearing based nuclear acid extraction and nucleic acid detection, with a sensitivity of 10 copies/µL, with no cross-reactivity with other 5 viruses. For 28 simulated samples, the integrated assay platform was consistent with the experimental results of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays after conventional laboratory nucleic acid extraction. The entire process can be finished in about 1 h, which is ideal for immediate rapid detection.
Surface-enhanced Raman scattering (SERS) spectroscopy has emerged as a powerful analytical technique for detecting and identifying trace chemical and biological molecules. In this review, we present an in-depth discussion of recent advances in the field of crystal phase manipulation to achieve exceptional SERS performance. Focusing on transition metal dichalcogenides, (hydr)oxides, and carbides as exemplary materials, we illustrate the pivotal role of crystal phase regulation in enhancing SERS signals. By exploring the correlation between crystal phases and SERS responses, we uncover the underlying principles behind these strategies, thereby shedding light on their potential for future SERS applications. By addressing the current challenges and limitations, we also propose the prospects of the crystal phase strategy to facilitate the development of cutting-edge SERS-based sensing technologies.
Dry powder inhalation represents a promising approach for the treatment of lung cancer, offering several advantages such as enhanced targeting, improved bioavailability, and reduced toxicity. However, traditional dry powder formulations suffer from limitations, notably low pulmonary delivery efficiency and inadequate penetration into tumor tissues, thereby limiting their therapeutic efficacy. In response to these challenges, we have developed an innovative trojan horse strategy, harnessing an inhalable nanoparticle-in-microsphere system characterized by tunable size, reversible charge, and mucus-penetrating capabilities. The inhalable nanoparticle-in-microsphere system exhibit stable structural properties, excellent environmental responsiveness and high biocompatibility. More importantly, the therapeutic effect of MTX@PAMAM@HA@Gel (MPHG) was demonstrated in vitro and in vivo. This system offers improved pulmonary delivery efficiency, enhanced drug retention within tumor tissues, and effective penetration, thus representing a promising strategy in lung cancer treatment.
Controlling the shape and composition of Pt-based nanocrystals is essential to improve electrocatalytic performance. In this work, we have carefully investigated the evolution process of morphology and composition for Pt and Pt3M (M = Ni, Co) nanocrystals by hydrochloric acid (HCl) etching. As a result, only Pt3Ni nanocrystals successfully formed unsaturated step-like atoms on the surface and then constructed high-index facets (HIFs), while Pt and Pt3Co preserved a good octahedron shape. Density functional theory (DFT) calculation suggests that Cl− ions can be tightly adsorbed on the surface of Pt3Ni rather than other nanocrystals, which hinders the deposition of newly-reduced atoms and thus regulating the surface morphology. Besides, the etching of surface transitional metals further accelerates the formation of HIFs. Boosted by the active sites on the surface, HCl-Pt-Ni exhibited a ~10.8 and ~11.3 times higher oxygen reduction reaction (ORR) mass and specific activities than commercial Pt/C catalyst, and possessed a good durability after 10,000 cycles test. This work gives a deep insight into the design of high-performance Pt-based ORR catalysts.
Electrocatalytic water splitting is the most directly available route to generate renewable and sustainable hydrogen. Here, we report the design of a composite material in which arrays of square pillar-like NiMoO4 nanorods coated with N, P-doped carbon layers are uniformly contained in numerous nested nanoparticle structures. The catalysts have superior catalytic activity, requiring only 59 mV and 187 mV for HER and OER to attain a current density of 10 mA/cm2, respectively. The assembled two-electrode electrolytic cell required a voltage of 1.48 V to reach 10 mA/cm2, along with excellent long-term stability. Theoretical calculations reveal that electrons aggregate and redistribute at the heterogeneous interface, with the d-band centers of the Ni and Fe atoms being positively shifted compared to the Fermi level, effectively optimizing the adsorption of intermediates and reducing the Gibbs free energy, thus accelerating the catalytic process. Meanwhile, an integrated solar-driven water-splitting system demonstrated a high and stable solar-to-hydrogen efficiency of 18.20%. This work provides new possibilities for developing non-precious metal-based bifunctional electrocatalysts for large-scale water splitting applications.
The development of clean renewable energy and energy storage devices is of great significance under the present energy crisis and environmental pollution background. Aqueous zinc-ion battery (ZIB) has become one of the most promising energy storage devices due to its high capacity, safety and low cost. However, the application of ZIB cathode is usually limited by low capacity and poor stability. Herein, we propose a novel heterostructure MnO/MnV2O4 composite material composed of MOF derivatives and spinel with dual active components as cathode for ZIBs. Benefited from substantial framework of MOF derivatives and the synergistic effect of heterostructures, MnO/MnV2O4 exhibits excellent rate performance (342 mAh/g at 0.1 A/g, 261 mAh/g at 15 A/g) and cycling performance (198.9 mAh/g at 10 A/g after 2000 cycles) in 3 mol/L Zn(CF3SO3)2 electrolytes. This work extends the range of developing high-performance cathodes for ZIBs under high current density and is expected to enlighten the optimization of commercial energy storage devices.