Elsevier最新文献

Detection of airborne chemical threats is an emerging challenge amidst the prevailing tumultuous global milieu. Extensive investigation has showcased the substantial promise of surface-enhanced Raman spectroscopy (SERS) for the on-site identification of hazardous chemicals present in liquid mediums, whether directly from a fluid source or through methodologies such as swab sampling. Nonetheless, exploration into the applicability of SERS for the detection of gas or vapor-phase chemical threats remains severely constrained. In this study, we present the successful realization of sub-parts per million (ppm) detection thresholds via SERS for hydrogen cyanide (HCN) and Tabun (GA) chemical warfare agents, facilitated by a custom-made gas sampling cell integrated with a Peltier cooling mechanism. The cooling regimen, spanning from 20 to -17 °C, verified a 140-fold increase in the SERS signal for 1 ppm HCN, concurrently enabling the detection of HCN and Tabun concentrations as low as 0.25 and 0.5 ppm, respectively. Implementation of temperature modulation and controlled flow routines substantially reduced detection times down to 240 s for HCN, with prospects for further optimization.

Metabolites identification is the major bottleneck in untargeted LC-MS metabolomics, primarily due to the limited availability of MS² information for most detected metabolites in data dependent acquisition (DDA) mode. To solve this problem, we have integrated the iterative, interval, and segmented window acquisition concepts to develop an innovative non-fixed segmented window interval data dependency acquisition (NFSWI-DDA) mode, which achieves comparable MS² coverage to data independent acquisition (DIA) mode. This acquisition strategy harnesses the strengths of both DDA and DIA, which could provide extensive coverage and excellent reproducibility of MS² spectra. Furthermore, utilizing the NFSWI-DDA data, we successfully acquired and identified a large-scale of multiple reaction monitoring (MRM) ion pairs, and transitioned them from high-resolution mass spectrometry (HRMS) to triple quadrupole mass spectrometry (TQ-MS). At last, a large-scale targeted metabolomics method was established practically. This method enables targeted analysis of 475 endogenous metabolites encompassing amino acids, nucleotides, bile acids, fatty acids, and carnitines, which could cover 9 major metabolic pathways as well as 65 secondary metabolic pathways. The established targeted method allows for semi-quantitative assessment of 475 metabolites while enabling quantitative analysis of 327 specific metabolites in biological samples. The method demonstrates immense potential in the detection of various biological samples, offering robust technical support and generating extensive data to advance applications in precision medicine and life sciences.

Poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) has been widely used as the hole transport layers (HTLs) for perovskite solar cells (PSCs), especially in all-perovskite tandems. However, the energy-level mismatch between PEDOT:PSS and perovskite leads to large voltage deficit in PSCs, and the dopant PSS with high acidity and hygroscopicity conspicuously deteriorates the device stability. Herein, a powerful strategy for constructing self-assembled polymer HTLs is developed by in-situ polymerization of functionalized 3,4-ethylenedioxythiophene with carboxylic acids as side groups. This strategy facilitates the formation of a self-assembled polymer monolayer to be strongly anchored on the glass substrate, and enables the elimination of the dependence of PSS doping for traditional PEDOT. The obtained polymer HTL PEDOT-l-COOH (PTLC) exhibits an appropriate energy-level alignment with the perovskite, which enhances the charge carrier collection at the interfaces. Besides, the self-assembled PTLC with high structural ordering favors the heterogeneous nucleation of perovskite, resulting in the formation of high-quality perovskite films with superior buried interfaces. Consequently, the inverted PSCs based on PTLC demonstrate a champion conversion efficiency of 20.30 % with a high open-circuit voltage of 1.03 V which are much higher than that of PEDOT:PSS-based devices (14.47 %, 0.79 V). More encouragingly, the unsealed devices with PTLC deliver outstanding operational stability by maintaining 90 % of initial efficiency for 950 h under ambient condition with a relative humidity of 30 % ± 5 %. This work opens a new avenue for developing self-assembled PEDOT-based HTLs for optoelectronic devices, and paves the way for further improving the performance of inverted PSCs.

The development of a novel multifunctional adsorbent for the sensitive detection and capture of antibiotic residues in environmental and food samples presents a significant challenge. In this study, we synthesized a pioneering nanocomposite, ILs@PC, by encapsulating task-specific ionic liquids (ILs) within nitrogen-doped porous carbon (PC) derived from metal-triazolate frameworks. This ILs@PC nanocomposite functions as a multifunctional adsorbent in dispersive solid-phase extraction (DSPE), enabling simultaneous sorptive removal, sensitive detection, and molecular sieve selection. The ILs@PC demonstrated enhanced adsorption efficiency and sensitivity for sulfonamide antibiotics (SAs) compared to the pristine PC, attributed to the nanoconfinement effect of the ILs and the influence of pore volume on this effect. When integrated with high-performance liquid chromatography (HPLC), the ILs@PC-based DSPE method achieved a detection limit of 0.75-1.88 μg L^-1 for SAs, along with satisfactory recoveries of 86.0 %-111.9 %. Additionally, a portable syringe device was developed to facilitate rapid on-site extraction and enrichment of SAs. The practicality of this method was validated through its successful application in detecting SAs in real samples, including lake water and milk. This approach highlights its potential for efficient and rapid monitoring of antibiotic residues in both environmental and food systems.

Drug-induced liver injury (DILI) is a crucial factor that poses a significant threat to human health. DILI process leads to the changes of reactive oxygen species and reactive nitrogen species content in cells, which leads to oxidative and nitrosative stress in cells. However, the high reactivity of hypochlorous acid (HOCl) and peroxynitrite (ONOO⁻), combined with a lack of in situ imaging techniques, has hindered a detailed understanding of their roles in DILI. Therefore, this paper reports a novel sequence-activatable dual-locked molecular probe HA-P3 for the identification and imaging of two DILI-related biomarkers. First, HA-P3 selectively reacts with reactive oxygen species HOCl to leave the recognition receptor diethyl thiocarbamate to form HA-P2. Subsequently, HA-P2 reacts with ONOO⁻, liberating the fluorophore 4-hydroxy-1,8-naphthalimide, which emits a strong fluorescence signal. The two-step reaction effectively reduces the probability of false positive in predicting DILI. HA-P3 achieved the sensitive detection of HOCl and ONOO^- in different cells and zebrafish. Furthermore, HA-P3 can distinguish between normal liver cells and hepatoma cells and monitored the elevated levels of HOCl and ONOO⁻ during acetaminophen (APAP)-induced cellular damage. It is worth noting that in the APAP-induced mouse model, the positive correlation between HOCl and ONOO^- and DILI was revealed, providing strong direct evidence for the relationship between oxidative/nitrosative stress and DILI.

A total of 57 European, Canadian and North American postage stamps, all in red shades, were analyzed with the main goal of unraveling which pigments or dyes were used to produce the red color in the period dated from 1841 to 1899. Both non-destructive techniques, including X-Ray Fluorescence (XRF), Fiber Optics Reflectance Spectra (FORS), and Steady State Fluorescence Spectroscopy, and destructive methods such as High-Performance Liquid Chromatography coupled with Diode-Array Detection (HPLC-DAD) and Electrospray Ionization High-Resolution Mass Spectrometry (ESI-HRMS), were utilized for a comprehensive analysis. The examined red shades were identified as originating from either a single pigment or dye, or a combination of both. XRF analysis detected red lead/litharge in 14 postage stamps, vermilion in 8 and iron oxide in 4. The mapping results obtained by this technique were shown to be very important in the determination of inorganic pigments. Most specimens contained a natural organic dye, with carminic acid being the most prevalent, appearing in 30 samples. In contrast, alizarin was identified in only 3 of the examined postage stamps. A synthetic dye, eosin Y, first synthesised by Heinrich Caro in 1871, was detected in 11 stamps and suggested by FORS and steady-state fluorescence in 6 others printed from 1879 onwards. HPLC-HRMS provided more detailed information on the natural colorant. In 19 samples both organic and inorganic dyes or pigments were found to coexist. It has been shown that spectroscopic techniques, when used with an appropriate database, can play a role in suggesting the presence of certain compounds that are subsequently detected by other techniques.

Salidroside is a phenylpropanoid glycoside with wide applications in the food, pharmaceutical, and cosmetic industries; however, the plant genus Rhodiola, the natural source of salidroside, has slow growth and limited distribution. In this study, we designed a novel six-enzyme biocatalytic cascade for the efficient production of salidroside, utilizing cost-effective bio-based L-Tyrosine as the starting material. A preliminary analysis revealed that the poor thermostability of the Bacillus licheniformis UDP-glycosyltransferase (EC 2.4.1.384) BlYjiC M6 is a bottleneck in the cascade. Therefore, a combined computational strategy was used to engineer it and finally obtained a mutant TSM6 (T304V/G307A/N309W/F123W/T344V/D271G) with a 134-fold longer half-life at 40 °C and a 13 °C higher T_m^app compared to M6. The integration of TSM6 into the cascade improved salidroside productivity significantly, while reducing residual intermediates. After further optimization, the whole-cell biocatalytic cascade achieved a high salidroside titer of 12.8 g·L^-1 in a 5 L bioreactor, giving a productivity of 0.53 g·L^-1·h^-1. This study provides a green and efficient biosynthetic process for salidroside production and highlights the potential of enzyme engineering to enhance the biocatalytic cascade.

With the global population expected to reach 10 billion by the 2050s, the demand for protein will surge, intensifying the need for high protein utilization efficiency. This study investigates the use of protease-enhanced Streptomyces sp. SCUT-3-3940 to degrade soybean meal (SBM) via solid-state fermentation (SSF). Optimized conditions resulted in anti-nutritional factors elimination and high soluble protein recovery (41.1 g/100 g), including bioactive oligopeptides (17.3 g/100 g) with antihypertensive and antioxidant properties. The degradation also produced free amino acids rich in essential amino acids, and other nutrient enhancing compounds. The fermented SBM (FSBM) exhibited superior digestibility, making it a valuable protein source. In a 60-day largemouth bass trial, replacing 10 % SBM with FSBM in feed significantly improved feed intake and weight gain. This method offers an efficient, eco-friendly, and cost-effective solution to address global protein shortages.

Hydrogels with antioxidant and antibacterial activities have received increasing attention in wound healing due to excessive reactive oxygen species (ROS) and bacterial infection are common issues associated with wounds. Herein, we constructed a series of hydrogels with C-phycocyanin (C-PC), quaternized chitosan (QCS) and silk fibroin protein (SF) as matrixes, which with tetrakis hydroxymethyl phosphonium sulfate (THPS) as crosslinking agent to form dynamic covalent bonds with C-PC and SF. The hydrogel exhibited excellent stretchability and compressibility, which with adhesion strength reached 15 ± 3 kPa and rapid self-healing properties. The hydrogel possessed strong antioxidant activity with assessments of DPPH radical-scavenging capacity and total reducing power. In addition, the hydrogel possessed obvious coagulation function and good blood compatibility, which also showed strong antibacterial activity against E. coli and S. aureus. To improve the therapeutic effect, polydeoxyribonucleotide (PDRN) with the ability of promote wound healing was introduced into the hydrogel. The results showed that the hydrogel loading with PDRN possessed high biocompatibility and can promote cell migration. More importantly, the hydrogel loaded with PDRN can effectively promote wound healing by exerting anti-inflammatory and antioxidant effects, which may offer promising potential application value in the field of wound dressing and tissue repair.