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Ternary metal sulfides with suitable band gaps, high physicochemical stability, and unique two-dimensional (2D) nanostructures are expected to be the next-generation high-performance gas sensors following the MOS type. Doping engineering is utilized as an effective strategy to improve the semiconductor surface activity and enhance its gas-sensitive properties. In this paper, the energy band structure and surface chemical oxygen of ZnIn₂S₄ (ZIS) materials was tuned by selectively introducing substitutional Cd to replace the Zn sites in ZIS crystals. Meanwhile, the introduction of Cd-ions brings more abundant S vacancy defects, enhances the acid-base interactions at the interface, and pushes the extent of surface redox reactions. In addition, by combining the strong adsorption of ZIS to triethylamine, the Cd_xZn_1-xIn₂S₄ nanosheets achieved highly improved sensing properties, including better response (63.38-100 ppm), enhanced selectivity (S_TEA/s_other = 12.9), and accelerated response/recovery (4 s/32 s). The results confirm the feasibility of developing low-cost, high-performance 2D metal sulfide gas sensing materials through rational structural design and optimization.

In this study, a nanozyme (ZIF-Co-Cys) with high oxidase-like catalytic activity was prepared, and a ratiometric fluorescent/photothermal dual-mode probe was constructed for organophosphorus pesticides (OPs) detection based on the competitive effect of ZIF-Co-Cys and the enzymatic reaction product of acid phosphatase (ACP) on o-phenylenediamine and the inhibition effect of OPs on ACP activity. Using dimethyl dichloroviny phosphate (DDVP) as the model, both the fluorescence intensity ratio and the temperature change of the probe solution exhibited an excellent correlation with OPs concentration. The detection limits were 1.64 ng/mL and 0.084 ng/mL, respectively. Additionally, the detection of DDVP residues in real samples verified the outstanding anti-interference and accuracy of the probe. This work not only provided a complementary dual-mode method for the accurate and rapid detection of OPs residues in complex samples, but also supplied a new insight into the design of a multi-mode sensing platform based on the cascade reaction of nanozyme.

As an important ROS species participating in various physiological and pathological processes, high level of hypochlorite (ClO^-) poses significant health and safety concerns, necessitating efficient detection methods. Herein, this study introduces a water-soluble fluorescent nanoprobe Nano-SJD, effectively detect ClO^- in both food samples and living cells. The small molecular probe SJD with N, N-dimethylthiocarbamyl (DMTC) as recognition moiety was constructed based on a naphthalene derivative. To further improve the water solubility, SJD was assembled with an amphiphilic copolymer (mPEG-DSPE) to prepare a water soluble fluorescent nanoprobe Nano-SJD. Fortunately, the nanoprobe preserves the excellent properties of small molecules and performs very well optical response to ClO^- in aqueous solution, possessing the advantages including ultra-rapid response (within 1 s), minimal interference, low detection limits (0.39 μM) and good pH stability. What's more important, we have also developed smartphone-compatible test paper strips for convenient on-site detection of ClO^- in real-water samples. Additionally, the robust fluorescent imaging behavior of Nano-SJD for visualization of ClO^- in living cells highlights its broad potential in biosystem applicability.

A method is proposed for increasing the number of ions during mass-spectrometric analysis of samples in a nonpolar solvent (benzene). For this purpose, aerodynamic thermal breakup droplet ionization (ATBDI) with the impact of β-radiation on the aerosol droplets used in ATBDI was evaluated. This modification of the method, which we named β-ATBDI, allows to shift a nonvolatile analyte (trinitrotoluene in the negative ionization region and cocaine in the positive ionization region, as an example) into a gas phase as an aerosol at room temperature (in contrast to atmospheric pressure chemical ionization). In addition, β-ATBDI enables a researcher to distinguish mass spectrometric peaks of the compounds located in an aerosol droplet from compounds located outside the droplet, i.e., to identify background peaks. Also briefly discussed the ionization of two antibiotics-azithromycin in methylene chloride and sulfadiazine in salt water with β-ATBDI, ATBDI and electrospray ionization source.

Oxylipins are powerful signalling compounds derived from polyunsaturated fatty acids (PUFAs) and involved in regulating the immune system response. A mass spectrometry-based method was developed and validated for the targeted profiling of 52 oxylipins (e.g., isoprostanoids, prostaglandins, epoxy- and hydroxy-fatty acids, specialized pro-resolving mediators) and 4 PUFAs in small urinary extracellular vesicles (uEVs). Ultrasound-assisted extraction using a 50:50 v/v MeOH:H₂O mixture ensured optimal analytical performances. Limits of detection ranged between 10 and 400 pg/mL for oxylipins and 0.10-3 ng/mL for PUFAs. Satisfactory recoveries (85-116 %) and good intra- and inter-day precisions (RSD ≤15 %) were obtained for all the analytes. The reliability of the procedure was tested in a real case scenario by monitoring ultramarathon runners during the world Tor des Géants® (TDG) race. Both F₂- and E₂-isoprostanes were detected in small uEVs of the ultramarathon runners, suggesting the onset of an oxidant insult. 5-F_2t-IsoP exhibited significant pre- to post-race variations, thus potentially representing a non-invasive marker of in-vivo lipid peroxidation. The presence of specialized pro-resolving mediators suggests the activation of pro-resolution signalling cascade resolving inflammation. These outcomes may help manage post-exercise recovery and improve training.

Peptidyl arginine deiminase 4 (PAD4) plays a critical role in many autoimmune diseases including rheumatoid arthritis. Herein, a trypsin assisted highly immunoassay method was established to determine PAD4 activity and screen potent inhibitors from herbal plants extracts and purified natural products. The method was applied to determine endogenous PAD4 activity in both cell and tissue lysates, as well as the inhibitory effects of 20 herbal plants and 50 purified natural products. The Cinnamomi ramulus extract showed strongest inhibitory potency with IC₅₀ value lower than 5 μg/mL. Meanwhile, pyrroloquinoline quinone (PQQ), widely used as a dietary supplement, was discovered as a promising PAD4 inhibitor with an IC₅₀ value lower than 4 μM. The inhibition kinetic analysis, drug affinity response target stability (DARTS) and molecular docking were performed to confirm the interaction between PQQ and PAD4. This method has great potential for researchers to monitor activities and discover potential inhibitors of PAD4.

Exposomics aims to measure human exposures throughout the lifespan and the changes they produce in the human body. Exposome-scale studies have significant potential to understand the interplay of environmental factors with complex multifactorial diseases widespread in our society and whose origin remain unclear. In this framework, the study of the chemical exposome aims to cover all chemical exposures and their effects in human health but, today, this goal still seems unfeasible or at least very challenging, which makes the exposome for now only a concept. Furthermore, the study of the chemical exposome faces several methodological challenges such as moving from specific targeted methodologies towards high-throughput multitargeted and non-targeted approaches, guaranteeing the availability and quality of biological samples to obtain quality analytical data, standardization of applied analytical methodologies, as well as the statistical assignment of increasingly complex datasets, or the identification of (un)known analytes. This review discusses the various steps involved in applying the exposome concept from an analytical perspective. It provides an overview of the wide variety of existing analytical methods and instruments, highlighting their complementarity to develop combined analytical strategies to advance towards the chemical exposome characterization. In addition, this review focuses on endocrine disrupting chemicals (EDCs) to show how studying even a minor part of the chemical exposome represents a great challenge. Analytical strategies applied in an exposomics context have shown great potential to elucidate the role of EDCs in health outcomes. However, translating innovative methods into etiological research and chemical risk assessment will require a multidisciplinary effort. Unlike other review articles focused on exposomics, this review offers a holistic view from the perspective of analytical chemistry and discuss the entire analytical workflow to finally obtain valuable results.

For the first time, we introduce a novel disposable and ultrasensitive sensing electrode made up of nanosized ceria uniformly loaded carbon nanofibers (CeNPs@CNF) sol-gel nanoceramic film (CF) wrapped on eco-friendly and inexpensive pencil graphite rods (PGRs) to explore their electro-catalytic detection of the anticancer drug capmatinib (CMB). The as-prepared CeNPs@CNF hybrid nanocomposite was described by XRD, SEM, TEM, HRTEM, and EDX analysis. The CV study clearly demonstrated that, the disposable CeNPs@CNF-CF/PGRE sensor exhibited excellent redox activities in the ideal probe [Fe(CN)₆]^3-/4-. Due to the outstanding electrochemical properties, larger electrochemically active surface area, and tremendous electro-catalytic activity of CeNPs@CNF, the reduction current of CMB on the CeNPs@CNF-CF/PGRE sensor is considerably higher than that of bare PGRE. The detection conditions, such as supporting electrolyte, pH of the buffer solution, amount of modifier, adsorption potential, and time, were studied and optimized. The sensing platform demonstrated high sensitivity (1.2 μA nM^-1 cm^-2), an ultralow detection limit (0.6 nM), and a wide linear range of 2.0 nM-400 nM of CMB compared to the bare PGRE. Additionally, the CeNPs@CNF-CF/PGRE sensor showed high selectivity, stability, and simple operation, which provided a promising alternative tool for fast detection of CMB in human body fluids with good recoveries.

Acute lung injury (ALI) is a serious pulmonary inflammatory disease resulting from excessive reactive oxygen species (ROS) which could cause the damage of the alveolar epithelial cells and capillary endothelial cells. Peroxynitrite, as one of short-lived reactive oxygen species, is closely related to the process of ALI. Thus, it is important to monitor the fluctuation of peroxynitrite in living system for understanding the process of ALI. Herein, the novel mitochondria-targeted fluorescent probe BHMT was designed to respond to peroxynitrite and pH with distinct fluorescence properties respectively. The absorption spectrum of the probe BHMT exhibited a notable red shift as the pH value declined from 8.8 to 2.6. Upon reaction with peroxynitrite, BHMT had a significant increase of fluorescence intensity (63-fold) with maintaining a detection limit of only 43.7 nM. Furthermore, BHMT could detect the levels of endogenous peroxynitrite and image the intracellular pH in ratiometric channels utilizing cell imaging. In addition, BHMT was successfully applied to revealing the relationship between the peroxynitrite and the extent of ALI. Thus, these results indicated the probe BHMT could be a potential tool for diagnosing the early stage of ALI and revealed the peroxynitrite was likely to be a crucial therapeutic target in ALI treatment.