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Given the threat to human health posed by the abuse of tetracycline (TC), the development of a portable, on-site methods for highly sensitive and rapid TC detection is crucial. In this work, we initially synthesized europium-doped silicon nanoparticles (Si Eu NPs) through a facile one-pot microwave-assisted method. Due to its blue-red dual fluorescence emission (465 nm/621 nm), which was respectively attributed to the silicon nanoparticles and Eu 3+ , Si Eu NPs were designed as a ratiometric fluorescent sensor for TC detection. For the dual-signal reverse response mechanism: TC quenched the blue emission from silicon nanoparticles through inner filter effect (IFE), and enhanced the red emission through "antenna effect" (AE) between TC and Eu 3+ , the nanoprobe was able to detect TC within a range of 0.2-10 μM with a limit of detection (LOD) of 10.7 nM. Notably, the equilibrium detection time was only 1 min, achieving rapid TC detection. Furthermore, TC was also measured in real samples (tap water, milk and honey) with recoveries ranging from 95.7 % to 117.0 %. More importantly, a portable smartphone-assisted on-site detection platform was developed, enabling real-time qualitative identification and semi-quantitative analysis of TC based on fluorescence color changes. This work not only provided a novel doped silicon nanoparticles strategy, but also constructed a ratiometric sensing platform with dual-signal reverse response for intuitive and real-time TC detection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A general one-pot protocol is reported to prepare hollow or porous manganese (Mn) oxide, phosphate, sulfide nanoparticles (NPs) via a controlled ion transfer process.

Graphene has attracted intense interest due to its exceptional physical and chemical properties as well as its wide potential applications. The processability and stability of this two-dimensional material in a variety of solvents have been the prerequisites for its functionalization, which will generate more interesting properties for further applications. In this mini review, we present and discuss the current status of liquid-phase exfoliation of graphene from various types of graphite, followed by a topical summarization of recent progress in the functionalization and applications of graphene., (© The Royal Society of Chemistry 2011)

Synthesis of multifunctional magnetic nanoparticles (MFMNPs) is one of the most active research areas in advanced materials. MFMNPs that have magnetic properties and other functionalities have been demonstrated to show great promise as multimodality imaging probes. Their multifunctional surfaces also allow rational conjugations of biological and drug molecules,making it possible to achieve target-specific diagnostics and therapeutics.This review fi rst outlines the synthesis of MNPs of metal oxides and alloy sand then focuses on recent developments in the fabrication of MFMNPs of core/shell, dumbbell, and composite hybrid type. It also summarizes the general strategies applied for NP surface functionalization. The review further highlights some exciting examples of these MFMNPs for multimodality imaging and for target-specific drug/gene delivery applications.

The characteristic of easy sintering of aluminum nanoparticle (ANP) limits its application in solid propellants. Coating ANP with fluoropolymer could effectively improve its combustion performance. To find out how the coating layer inhibits sintering and promotes complete combustion of particles from an atomic view, a comparative study has been done for bare ANP and PTFE coated ANP by using reactive molecular dynamics simulations. The sintering process is quantified by shrinkage ratio and gyration radius. Our results show that, at the same heating rate and combustion temperatures, bare ANPs are sintered together after the temperature exceeds the melting point of aluminum but the decomposition of PTFE coating layer pushes particles away and increases reaction surface area by producing small AleF clusters. The sintering of ANPs which are heated in PTFE is alleviated compared with particles heated in oxygen, but particles still sinter together due to the lack of intimate contact between PTFE and alumina surface. The effect of temperature on the combustion of PTFE coated ANPs is also studied from 1000 to 3500 K. The number density analysis shows the particles will not be sintered at any temperature. Aluminum fluoride prefers diffusing to the external space and the remained particles are mainly composed of Al, C and O. Fast ignition simulations are performed by adopting micro canonical ensemble. With the expansion of aluminum core and the melting of alumina shell, bare ANPs are sintered into a liquid particle directly. For PTFE coated ANPs, the volatilization of gaseous aluminum fluoride products continually endows particles opposite momentum. [ABSTRACT FROM AUTHOR]

A type of MoS2 nanoparticle with a spherical‐like shape is chemically synthesized with favorable third‐order and suppressed second‐order nonlinear optical response, which results from the isotropy induced by the geometrical uniformity of nanoparticles and an artificial symmetry center. It is found that the linewidth of third harmonic signal is broadened due to the self‐phase modulation effect, another third‐order nonlinearity. Moreover, the intensity of harmonic signal can be conveniently adjusted by controlling the polarization state of applied optical field. The artificially designed material morphology may provide a reference for designing all‐optical modulation devices. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are inevitably released into the aquatic environment for being widely used and may affect the toxicity of other contaminants already present in the environment, such as trace metals. However, the effects of NPs on the ecotoxicity of cadmium (Cd), a common environmental trace metal pollutant, are not well explored. In this study, effects of four widely used NPs TiO 2 (n-TiO 2 ), SiO 2 (n-SiO 2 ), Ag (n-Ag) and CdTe/CdS core/shell quantum dots (QD) on the toxicity of Cd to the freshwater algae Chlamydomonas reinhardtii were assessed respectively. Cd reduced the algae biomass, impaired the photosynthetic activities, and led to intracellular oxidative stress of algae. At non-toxic concentrations, both n-TiO 2 (100 mg L −1 ) and n-SiO 2 (400 mg L −1 ) attenuated the toxicity of Cd towards the algae for reducing the intracellular Cd contents, and the former was more pronounced. QD (0.5 mg L −1 ) increased the toxicity of Cd to algae, but n-Ag (0.2 mg L −1 ) had no significant influence on the Cd toxicity to algae. The microscopic observations on the ultrastructure of algae cells presented the same phenomena and n-TiO 2 , n-SiO 2 aggregations were clearly observed outside the cell wall. Furthermore, the regulation of NPs to the Cd toxicity towards algae was related to the intracellular nitric oxide (NO), an important signaling molecule, rather than the phototaxis of algae. Above all, this study provided a basic understanding about the difference in joint toxicity of different kinds of NPs and Cd to aquatic organisms. [ABSTRACT FROM AUTHOR]

A general one-pot protocol is reported to prepare hollow or porous manganese (Mn) oxide, phosphate, sulfide nanoparticles (NPs) viaa controlled ion transfer process. [ABSTRACT FROM AUTHOR]