Sensitive detection of Golgi protein 73 by magnetic separation combined with a dual nanozyme MOF-818 and magnetic nucleus@bifunctional shell (FeO@PB-Au) cascade reaction catalytic amplification strategy.

Metal-organic framework (MOF-818) and nanocomposite (FeO@PB-Au) dual nanozymes for enhanced cascade signal amplification were designed. MOF-818 has excellent catechol oxidase mimetic activity and catalyzes the production of color and generation of hydrogen peroxide from the substrate 3,5-di--butylcatechol (3,5-DTBC). Subsequently, FeO@PB-Au with peroxidase-like activity catalyzes the generation of reactive oxygen species from hydrogen peroxide, which oxidizes 3,3',5,5'-tetramethylbenzidine (TMB) to generate the oxidized state of oxTMB, resulting in a signal-enhancing effect.

Biomolecular condensation of ERC1 recruits ATG8 and NBR1 to drive autophagosome formation for plant heat tolerance.

Macroautophagy (hereafter autophagy) is essential for cells to respond to nutrient stress by delivering cytosolic contents to vacuoles for degradation via the formation of a multi-layer vesicle named autophagosome. A set of autophagy-related (ATG) regulators are recruited to the phagophore assembly site for the initiation of phagophore, as well as its expansion and closure and subsequent delivery into the vacuole. However, it remains elusive that how the phagophore assembly is regulated under different stress conditions.

Hydrangea-like AuPtRu/ZnO-rGO Nanocomposites with Enhanced Peroxidase Mimiking Activity for Senitive Colorimetric Determination of HO.

In this study, a facile and cost-effective hydrothermal synthesis method was used to synthesize zinc oxide nanoflowers modified by reduced graphene oxide, and subsequently, trimetallic AuPtRu nanoparticles(AuPtRuNPs) were supported via the reduction method for high-sensitivity colorimetric detection of HO in weakly acidic solutions. Compared to monometallic and bimetallic nanoparticles, trimetallic nanoparticles exhibit significant synergistic effects and enhanced catalytic activity. After providing a three-dimensional structure with multiple pores by zinc oxide and enhancing electron transfer ability by reduced graphene, the trimetallic nanocomposites (AuPtRu/ZnO-rGO) exhibited excellent peroxidase-mimicking activity, which can effectively catalyze 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue oxidation product (oxTMB) in the presence of HO.

Electrochemical immunosensor based on hollow Pt@CuO as a signal label for dual-mode detection of procalcitonin.

As a reliable biomarker to evaluate the severity of sepsis, sensitive and accurate detection of procalcitonin (PCT) is essential. In this study, a dual-mode electrochemical immunosensor based on Au/ZIF-8 as substrate and Pt@CuO as signal label was constructed for the detection of PCT. By loading Au nanoparticles onto rhombic dodecahedral ZIF-8, the substrate (Au/ZIF-8) has large specific surface area and can immobilize antibody (Ab) by Au-N bonds.

An ultrasensitive electrochemical immunosensor for carcinoembryonic antigen detection based on two-dimensional PtPd/Cu-TCPP(Fe) nanocomposites.

Establishing an effective signal amplification strategy is the key to achieving sensitive detection of analytes by electrochemical immunoassay. In this work, a novel sandwich-type electrochemical immunosensor with dual-signal amplification was successfully constructed using PtPd/Cu-TCPP(Fe) as the sensing platform and mesoporous silicon dioxide as the signal amplifier. Firstly, two-dimensional wrinkled Cu-TCPP(Fe) nanomaterials loaded with PtPd nanoparticles have strong affinity for the immobilization of capture antibodies and can generate excellent electrochemical signals.

Suppressing Non-Radiative Relaxation through Single-Atom Metal Modification for Enhanced Fluorescence Efficiency in Molybdenum Disulfide Quantum Dots.

To enhance the fluorescence efficiency of semiconductor nanocrystal quantum dots (QDs), strategies via enhancing photo-absorption and eliminating non-radiative relaxation have been proposed. In this study, we demonstrate that fluorescence efficiency of molybdenum disulfide quantum dots (MoS QDs) can be enhanced by single-atom metal (Au, Ag, Pt, Cu) modification. Four-fold enhancement of the fluorescence emission of MoS QDs is observed with single-atom Au modification.

Highly sensitive electrochemical aptasensor for SARS-CoV-2 antigen detection based on aptamer-binding induced multiple hairpin assembly signal amplification.

In this work, a brief electrochemical aptasensor was developed for highly sensitive detection of SARS-CoV-2 antigen utilizing an aptamer-binding induced multiple hairpin assembly strategy for signal amplification. In the presence of SARS-CoV-2, a pair of aptamers was brought in a close proximity according to the aptamer-protein antigen binding, which initiated strand displacement reaction thereby triggering a multiple hairpin assembly to obtain long linear DNA concatemers on the electrode surface. As the fabricated hairpin probes were labeled with biotin, massive streptavidin-alkaline phosphatases (ST-ALP) could be further introduced on the electrode interface via biotin-streptavidin interaction thus generating strong electrochemical signal in electrolyte solution containing 1-naphthol phosphate.

Morphologically Flex Sm-MOF Based Electrochemical Immunosensor for Ultrasensitive Detection of a Colon Cancer Biomarker.

Despite having the potential to synthesize stable metal-organic frameworks (MOFs), rare earth metal-based MOFs have not been exploited extensively. Owing to the high coordination numbers, the MOFs can generate a suitable coordination environment for various applications. Herein, samarium (Sm)-based MOFs were synthesized with three different organic linkers, namely, trimesic acid (TMA), -tetra(4-carboxyphenyl)porphine (TCPP), and 1,3,6,8-tetra(4-carboxylphenyl) pyrene(TBPy) by the solvothermal approach.

Cigarette taxation and price differentials in 195 countries during 2014-2018.

Introduction: Raising tobacco prices via increased taxation may be undermined by tobacco industry tactics to keep budget cigarettes on the market. Price differentials between budget and premium cigarettes allow smokers to trade down in the face of average price rises thus attenuating health benefits. This study examines global trends of price differentials and associations with taxation.

A multilayered cross-species analysis of GRAS transcription factors uncovered their functional networks in plant adaptation to the environment.

Introduction: Environmental stress is both a major force of natural selection and a prime factor affecting crop qualities and yields. The impact of the GRAS [gibberellic acid-insensitive (GAI), repressor of GA1-3 mutant (RGA), and scarecrow (SCR)] family on plant development and the potential to resist environmental stress needs much emphasis.

Objectives: This study aims to investigate the evolution, expansion, and adaptive mechanisms of of important representative plants during polyploidization.

Two similar Schiff-base receptor based quinoline derivate: Highly selective fluorescent probe for Zn(II).

As is known, Zn plays a vital role in a variety of biological processes but excessive exposure of Zn to human beings can cause toxicity, inducing a series of overt poisoning symptoms and neurodegenerative disorders. Thus, we designed and synthesized two quinoline-derived Schiff-bases HL and HL, and investigated the fluorescence emission responses of these two Schiff-bases to various metal ions. A significant enhancement in fluorescence emission band centered at 450 nm was observed in the ethanolic solution of HL with addition of Zn, while remarkably lower fluorescence emission enhancement was obtained in the case of HL in which one methyl group was introduced to the azomethine carbon.

Target-inspired Pb-dependent DNAzyme for ultrasensitive electrochemical sensor based on MoS-AuPt nanocomposites and hemin/G-quadruplex DNAzyme as signal amplifier.

In this work, a novel Pb electrochemical DNAzyme sensor was developed for ultrasensitive detection of lead ions (Pb) in water environment by coupling with the MoS-AuPt nanomaterials and hemin/G-quadruplex DNAzyme, which acting as the electrocatalytic signal tag. Streptavidin (SA) modified tin dioxide-functionalized reduced graphene oxide (rGO-SnO) /gold nanoparticles (AuNPs) served as a sensor platform for enhancing conductivity and immobilizing more Pb-specific DNAzyme. In the presence of Pb, the Pb-dependent DNAzyme specifically reacted with Pb, cleaving the substrate strand (SS) into two free fragment and releasing the biotin-modified enzyme strand (Bio-ES) on the electrode.

A triple-amplification differential pulse voltammetry for sensitive detection of DNA based on exonuclease III, strand displacement reaction and terminal deoxynucleotidyl transferase.

In this research, a sensitive and specific electrochemical biosensor for DNA detection was constructed. The highly sensitivity of this biosensor is due to the exploitation of exonuclease III-assisted double recycling and toehold-mediated strand displacement recycling to achieve the target triple recycling amplification, thus generating a large amount of Y-shaped DNA structures. Combination with a terminal deoxynucleotidyl transferase (TDT)-mediated cascaded signal amplification strategy can catalyze the repetitive incorporation of biotin-dUTP to the 3'-OH of the Y-shaped DNA.

Dysprosium-doped iron oxide nanoparticles boosting spin-spin relaxation: a computational and experimental study.

Early diagnosis of diseases by contrast-enhanced magnetic resonance imaging (MRI) using iron oxide superparamagnetic nanoparticles (IOSNPs) has been extensively investigated due to the good biocompatibility of modified IOSNPs. However, the low magnetic sensitivity of IOSNPs still inflicts a certain limitation on their further application. In this study, we employed first-principles calculations based on spin-polarized density functional theory (SDFT) to find the optimal dysprosium-doped scheme for improving the magnetic sensitivity of IOSNPs.

A Schiff-base receptor based chromone derivate: Highly selective fluorescent and colorimetric probe for Al(III).

Upon excitation of the visible light, probes show colorimetric and fluorescent responses to the specific metal ion, which can be easily detected by the naked eye. Owing to the excitation of the visible light at 423 nm, a novel and simple Schiff-base receptor based chromone derivative called 7-methoxychromone-3-carbaldehyde-(indole-3-formyl) hydrazone (MCIH2) had been investigated as a selective and sensitive probe for Al with colorimetric and fluorescent responses. Upon addition of Al to compound MCIH2 solution, compound MCIH2 could respond to Al with a good selective colorimetric signal, which was easily observed from colorless to yellow-green by the naked eye.

A novel chromone and rhodamine derivative as fluorescent probe for the detection of Zn(II) and Al(III) based on two different mechanisms.

In this study, a novel fluorescent probe, 6‑hydroxychromone‑3‑carbaldehyde‑(rhodamine B carbonyl) hydrazine (L), for Zn and Al was designed and synthesized. Initially, this probe L exhibited inferior fluorescence emission peak centered at 488 nm in EtOH/HEPES solution (3/1, 10.0 μM HEPES, pH 7.

A signal-decreased electrochemical immunosensor for the sensitive detection of LAG-3 protein based on a hollow nanobox-MOFs/AuPt alloy.

In this work, hollow nanobox metal-organic framework (HNM) nanocomposites were synthesised and utilised for the first time in a signal decreased electrochemical immunosensor for the ultrasensitive quantitative determination of lymphocyte activation gene-3 (LAG-3) protein, which is a newly discovered biomarker. With the aid of signal materials, namely, SiO-tagged anti-LAG-3 antibody (SiO-Ab) and the biotin-streptavidin system, the sensor can achieve signal amplification. Encapsulation of tin dioxide-functionalised reduced graphene oxide (rGO-SnO) and gold and platinum alloys (AuPt alloys) onto the surface of hollow nanobox metal-organic frameworks (MOFs) was performed to prepare rGO-SnO/hollow nanobox-MOFs/AuPt alloys (rGO-SnO/HNMs/AuPt) as the matrix.

Luminescent magnetic nanoparticles encapsulated in MOFs for highly selective and sensitive detection of ClO/SCN and anti-counterfeiting.

It is well-known that ClO- and SCN- can cause adverse effects on the environment and organisms; therefore, development of new strategies for detecting ClO- and SCN-, especially in water, are highly desirable. Here, we present luminous Eu(iii) complex-functionalized Fe3O4 nanoparticles encapsulated into zeolitic imidazolate framework materials (nano-ZIF-8) and successfully employ this nano-MOF as a fluorescence probe for selective and sensitive detection of ClO- and SCN-. The introduction of ClO- into nano-ZIF-8 solution induced a significant decrease in the characteristic fluorescence emission of Eu3+ at 613 nm.

MRI relaxivity enhancement of gadolinium oxide nanoshells with a controllable shell thickness.

Gadolinium oxide-based core-shelled nanoparticles have recently emerged as novel magnetic resonance imaging contrast agents for high relaxivity and tumor targeting. However, their relaxivity enhancement mechanism has not yet been clearly understood. We prepared highly dispersible and uniform core-shell structured nanoparticles by encapsulating silica spheres (90 nm in diameter) with gadolinium oxide shells of different thicknesses (from 1.

A highly selective and sensitive fluorescent chemosensor and its application for rapid on-site detection of Al.

In this paper, a simple naphthalene-based derivative (HL) has been designed and synthesized as a Al-selective fluorescent chemosensor based on the PET mechanism. HL exhibited high selectivity and sensitivity towards Al over other commonly coexisting metal ions in ethanol with a detection limit of 2.72nM.

Tumor-targeted nanoprobes for enhanced multimodal imaging and synergistic photothermal therapy: core-shell and dumbbell Gd-tailored gold nanorods.

Multifunctional nanoprobes, due to their unique nanocomposite structures, have prominent advantages that combine multimodal imaging of a tumor with photothermal therapy. However, they remain a challenge for constructing nanostructures via conventional approaches due to the peculiar environmental sensitivity of each component. Here, we report the design and synthesis of Gd-based nanoparticle-tailored gold nanorods with distinctive core-shell and dumbbell nanoarchitectures (NAs) by a specific synthesis technology.

Electrochemical aptasensor for thrombin using co-catalysis of hemin/G-quadruplex DNAzyme and octahedral CuO-Au nanocomposites for signal amplification.

In this work, novel octahedral CuO-Au nanocomposites were synthesized and first applied in an electrochemical aptasensor to detect thrombin (TB) with the aid of a DNAzyme for signal amplification. The octahedral CuO-Au nanocomposites have not only simultaneously served as signal amplifying molecules but have also been utilized as an ideal loading platform to immobilize a large number of electroactive substances and recognition probes. Gold nanoparticles (AuNPs) were grown directly on the surface of the octahedral CuO nanocrystals, and the CuO-Au nanocomposites obtained had the advantages of large surface areas and excellent biocompatibilities.

Structure and dysprosium dopant engineering of gadolinium oxide nanoparticles for enhanced dual-modal magnetic resonance and fluorescence imaging.

We report a class of multi-functional core-shell nanoarchitectures, consisting of silica nanospheres as the core and GdO:Dy nanocrystals as the ultra-thin shell, that enable unique multi-color living cell imaging and remarkable in vivo magnetic resonance imaging. These types of targeted cell imaging nanoarchitectures can be used as a variety of fluorescence nanoprobes due to the multi-color emissions of the GdO:Dy nanophosphor. We also proposed a strategy of modulating core-shell structure design to achieve an enhanced magnetic resonance contrast ability of GdO nanoagents, and the classical Solomon-Bloembergen-Morgan theory was applied to explicate the mechanism underlying the enhancement.

Development of a coumarin-furan conjugate as Zn ratiometric fluorescent probe in ethanol-water system.

In this study, a novel coumarin-derived compound bearing the furan moiety called 7-diethylamino-3-formylcoumarin (2'-furan formyl) hydrazone (1) has been designed, synthesized and evaluated as a Zn ratiometric fluorescent probe in ethanol-water system. This probe 1 showed good selectivity and high sensitivity towards Zn over other metal ions investigated, and a decrease in fluorescence emission intensity at 511nm accompanied by an enhancement in fluorescence emission intensity at 520nm of this probe 1 was observed in the presence of Zn in ethanol-water (V : V=9 : 1) solution, which provided ratiometric fluorescence detection of Zn. Additionally, the ratiometric fluorescence response of 1 to Zn was nearly completed within 0.

A Novel Chromone Schiff-Base Fluorescent Chemosensor for Cd(II) Based on C=N Isomerization.

A new chromone Schiff-base fluorescent probe 7'-methoxychromone-3'-methylidene-1,2,4-triazole-3-imine (L) was designed and synthesized for selective recognition Cd(2+). With the fluorescence titration and the ESI-MS data, we reach the conclusion that the binding mode of the ligand-metal (L-Cd (2+) ) complex is 1:1. The sensor showed a strong fluorescence enhancement in ethanol system of Cd(2+) (excitation 409 nm and emission 462 nm) and the sensing mechanism based on the fact that C=N isomerization can be used to explain this phenomenon.