查找使用阿拉丁产品的科研文献

A novel colorimetric lead ion detection method using lead-2′3-dimercaptosuccinic acid chelates to catalyze etching of gold nanostars

Yuhuai Qin,Wenxue Sun,Joseph Brake,Sulin Gao,Qianqian Li,Xinrong Zhu,Jiang Bian,Xiaobin Wu

Lead ions are an environmental pollutant and a threat to human health. Traditional methods for detecting lead ions suffer disadvantages such as being time-consuming and expensive, therefore there is a need to develop simpler and faster methods. We developed an optimized spectroscopic method to detect lead ions by first identifying a lead-specific chelator 2,3-dimercaptosuccinic acid (DMSA) which was screened using a novel biological screening system and verified by metal chromophore assays. Synthetic gold nanostars (GNSs) were explored for use as probes and we found that DMSA-Pb chelates catalyzed the etching of GNSs in solution resulting in a color change. We observed a change in the longitudinal local surface plasmon resonance (LSPR) peak of GNSs in the presence of DMSA-Pb which could be measured in subsequent experiments. The optimized etching reaction displayed strong sensitivity and selectivity for Pb 2+ and achieved a detection limit of 2 nM less than 2 minutes, which is well below the safety threshold of Pb 2+ in environmental water and food. The Pb 2+ contents of rice, beans, milk, grapes, peaches, and cabbage were detected by the DMSA-Pb GNSs method and were consistent with those of inductively coupled plasma mass spectrometry (ICP-MS). Our study provides a novel and practical approach for rapid, safe, and cost-effective detection of lead ions.

La3+-substituted Nd2[Zr0.89(Bi0.5Ta0.5)0.11]3(MoO4)9 ceramics: structure, dielectric properties, Raman analysis, and P–V–L theory

Tang Ruxuan,Chen Yuan-Bin,Su Xiuyuan,Tang Ling

With the rapid development of 5G/6G mobile communication technology, microwave dielectric materials are facing increasingly strict performance requirements. As core fundamental materials for modern communication systems, performance optimization of microwave dielectric ceramics has become a research hotspot. Addressing the limitations of single-phase ceramic materials, dense microwave dielectric ceramics of (Nd 1- x La x ) 2 [Zr 0.89 (Bi 0.5 Ta 0.5 ) 0.11 ] 3 (MoO 4 ) 9 ( x  = 0.01, 0.03, 0.05, 0.07) were prepared by the conventional solid-state reaction method. The experimental process involved 550 °C pre-sintering followed by gradient sintering at 600–725 °C (4 h holding time). X-ray diffraction (XRD) analysis confirmed that all samples exhibited trigonal crystal structure with \(R\overline{3} c\) space group. The lattice parameters were obtained by Rietveld refinement method. Scanning electron microscopy (SEM) characterization indicates that compactness has a significant impact on the dielectric constant ( ε r ) and the quality factor ( Q  ×  f ). Raman spectroscopy analysis indicated strong associations of ε r and Q  ×  f values with characteristic peak shifts and full width at half maximum ( FWHM ), respectively. When sintered at 675 °C, the NLZBTM ( x  = 0.03) ceramics exhibited exceptional comprehensive performance: ε r  = 11.24 ± 0.02, Q  ×  f  = 116,914 ± 5738 GHz, and τ f  = − 37 ± 1.5 ppm/℃. The bond property analysis based on the P–V–L theory shows that the ionicity of the Nd/La–O bond makes the greatest contribution to εᵣ , while the covalency of the Mo–O bond significantly affects the Q  ×  f value and τ f parameter. It is noteworthy that this material achieves low-temperature sintering at 675 °C while maintaining excellent microwave dielectric properties, demonstrating significant potential as a candidate material for low-temperature co-fired ceramics (LTCC).

Facile Aptasensor with enhanced electrochemiluminescence by nanozyme in nanoporous silica film for highly sensitive detection of carbohydrate antigen 15–3

Liuyi Huang,Xinhui Gu,Fengna Xi

Establishing sensitive detection method for carbohydrate antigen 15–3 (CA15–3) is of great significance for the early diagnosis and therapeutic monitoring of breast cancer. Herein, an electrochemiluminescence (ECL) sensor was fabricated by growing Co 3 O 4 nanoparticles in-situ within nanochannels and employing a signal gating strategy, achieving highly sensitive detection of CA15–3. Using simple Stöber method, a silica nanochannel film (SNF) was deposited onto an indium tin oxide (ITO) glass electrode. This two-dimensional (2D) nanoporous silica film provided a confined space, within which Co 3 O 4 nanozymes were synthesized in situ. Co 3 O 4 served as a peroxidase (POD)-mimic nanozyme, enabling the catalytic conversion of hydrogen peroxide (H 2 O 2 ) into reactive oxygen species (ROS). Functioning as a nanocatalyst, Co 3 O 4 remarkedly enhanced the electrochemical oxidation of luminol, thereby boosting the ECL signal. This dual enhancement mechanism enabled the sensor to achieve high luminol-based ECL signal. The bio-recognition interface was constructed by functionalizing the outer surface of SNF with silane coupling agents and immobilizing aptamers. A measurable decrease in the ECL signal was generated due to the hindered diffusion of the emitter and co-reactant and increased interfacial resistance, which occurred when the aptamer-CA15–3 complex formed on the electrode surface. This response allowed for the quantification of CA15–3. Under optimal conditions, the developed aptasensor can detect CA15–3 in the range of 0.1 to 10,000 mU/mL, with a limit of detection of 26 μU/mL. Owing to its merits of simple fabrication, rapid analysis, high sensitivity, good reproducibility, and excellent selectivity, the developed immunosensor holds great potential for clinical diagnostics of tumor biomarkers.

Indole-3-Acetic Acid Improves Intestinal Inflammation and Intestinal Barrier Dysfunction In Vitro via the AHR/NF-κB Signaling Pathway

Qiaoyu Sun,Qingqing Zhou,Sitong Ge,Danli Wu,Ping Li,Qing Gu

Impairment of intestinal barrier function is intricately linked to intestinal inflammation. Emerging evidence highlights that tryptophan-derived metabolites from the intestinal microbiota play a crucial role in maintaining the homeostasis of intestinal barrier function. In this study, a Caco-2/HT29 co-culture model was applied to evaluate the effects of indole-3-acetic acid (IAA) on the intestinal barrier and explore its underlying mechanism of action. Results demonstrated that lipopolysaccharide (LPS) caused the transepithelial resistance to drop to 387.5 ± 30.41 Ω·cm 2 , while IAA was able to increase it to 542 ± 31.11 Ω·cm 2 . At the same time, it reduced the paracellular permeability and restored the FITC-Dextran 4 (FD-4) permeability to 108.01%. This phenomenon was accompanied by an upregulation in the expression of tight junction (TJ) proteins. Concurrently, after IAA intervention, aryl hydrocarbon receptor (AHR) pathway was activated, while nuclear factor kappa-B (NF-κB) pathway was significantly inhibited. Furthermore, IAA exerted an inhibitory effect on the LPS-triggered upregulation of inflammatory factors (TNF-α, IL-6, IL-8) in RAW264.7 cells. These findings provide novel insights into the enhancement of intestinal barrier function and the in vitro anti-inflammatory properties of gut microbiota-derived metabolites.

Molecularly imprinted polyphenylboronic acid/carboxylated graphene-based electrochemical sensor for ultrasensitive detection of 3-monochloropropane-1,2-diol in soy sauces

Suozhu Wu,Hao Wu,Guojuan Zhang,Hongyuan Guo

3-Monochloropropane-1,2-diol (3-MCPD) is a common contaminant generated during the heating process of foods. Because of the potential carcinogenic and toxic effects, measuring 3-MCPD is greatly significant to guarantee food security. Here, we developed a molecularly imprinted polyphenylboronic acid/carboxylated graphene (MIPPBA/CG)-based electrochemical sensor to determine 3-MCPD. The MIPPBA/CG composites were prepared by in-situ electrochemical deposition, and CG and MIPPBA were respectively used for electrical signal amplification and specific recognition of 3-MCPD. 3-MCPD was tested by square wave voltammetry utilizing the potassium ferricyanide probe. Under the optimal experimental conditions, our results showed that this sensor had the advantages of simplicity, rapidity, wide response range (1.0 × 10 −12 –1.0 × 10 −3  M), low detection limit (1.4 × 10 −13  M), good reproducibility, excellent stability, and high selectivity, and could detect the 3-MCPD content in different soy sauce samples with satisfactory results, which provided a promising approach for testing the food processing contaminant.

Co-pyrolysis of Li(Ni1/3Co1/3Mn1/3)O2 cathodes and polyvinyl chloride plastics for enhanced lithium-ion battery recycling

Jinchuan Dai,Tingting Shen,Zhe Meng,Zuotai Zhang,Xiao-Ying Lu,Feiyun Sun,Yuanyuan Tang

As the production and consumption of electronic products increasingly rely on ternary lithium-ion batteries, the need for effective recycling and disposal methods for these batteries becomes crucial. This study introduces a novel, efficient co-pyrolysis method for recycling Li(Ni 1/3 Co 1/3 Mn 1/3 )O 2 (NCM) cathode materials from spent ternary lithium-ion batteries. Employing a 1.0:0.35 mass ratio of NCM: polyvinyl chloride (PVC) in an oxygen-free environment, high recovery rates of Li (91.3 %), Ni (93.5 %), Co (93.6 %), and Mn (94.5 %) metals are achieved. The NCM cathode materials begin to decompose at temperatures below 500℃ and are fully reduced and segregated into Ni-Co alloy, MnO, and Li 2 CO 3 at 550℃ in this process. Notably, the decomposition and reduction temperature of 550℃ is significantly lower than those reported in other studies. Moreover, the NCM cathode material, were regenerated from the pyrolysis products through a straightforward high-temperature solid-phase process, and the regenerated NCM demonstrates remarkable electrochemical properties with strong cycling and rate performance. This method significantly contributes to environmental conservation, offering a green solution for recycling ternary battery waste while also addressing the challenge of waste PVC plastics. This dual-faceted approach mitigates environmental burden and resource wastage, marking a stride towards sustainable waste management and circular economy.

The performance optimization and specific adsorption of L-phenylalanine imprinted polymers using 1-vinyl-3-carboxymethylimidazolium chloride as functional monomer

Bo Gao,Ping Guan,Xiaoling Hu,Liwei Qian,Qiaoli Wang,Longfei Yang,Dan Wang

L-Phenylalanine (L-Phe) imprinted polymers (L-MIPs) were prepared via precipitation polymerization using 1-vinyl-3-carboxymethylimidazolium chloride ([VCIM]Cl) as functional monomer, which could interact with L-Phe through electrostatic interactions, hydrogen-bonding, and π–π interactions. The morphologies of obtained polymers were observed by a scanning electron microscope, and their structures were analyzed by Fourier transform infrared spectroscopy. The effects of monomer species and molar ratio of template to functional monomer or crosslinker on adsorption capacity and imprinting factors (IFs) of polymers were investigated. The result indicated that [VCIM]Cl was preferable monomer and the optimum molar ratio of template to functional monomer and crosslinker was 1:4:16. The maximum IF of the obtained L-MIPs could reach 3.86 in 0.4 mg mL−1 L-Phe solution at 25 °C, after 8 h of adsorption and the maximum adsorption capacity of L-MIPs for L-Phe was 33.08 mg g−1. The adsorption behavior of L-Phe on the L-MIPs was construed seriously within the experimental concentration by Freundlich model and Langmuir model. In terms of the higher correlation coefficient, it was considered that the adsorption behavior of L-Phe fit Freundlich model better than Langmuir model, which means that the distribution of active sites was heterogeneous in L-MIPs. The selectivity adsorption showed L-MIPs have better specificity and selectivity for L-Phe than that of L-His and L-Trp. Finally, L-MIPs were applied to the CD and Automatic Polarimeter experiments, showing that L-MIPs had the capability of specific chiral recognition for L-Phe.

The early Cambrian (Series 2, Stage 3) burrows from the Nagaur Sandstone, Marwar Supergroup, Rajasthan, India: palaeoenvironmental and palaeoecological considerations

Shamim Ahmad,S. K. Pandey,Mukund Sharma,Ayushi Srivastava

Design of a β-cyclodextrin-modified FeOOH/Al(OH)3 hybrid with interfacial activation for synergistic tetracycline enrichment and stabilization

Yi Ming Jun

β-CD to Fe-Al oxyhydroxide e − transfer induces positive ESP shift, forming e − -deficient cavity. • Activated β-CD cavity enhances TC affinity, supported by experiments and simplified DFT. • Composite achieves 152 mg/g capacity and good reusability and selectivity. • Cooperative enrichment-stabilization: β-CD recognition & Fe coordination. The development of high-performance adsorbents is often constrained by an inherent trade-off between rapid sequestration kinetics and strong binding capacity. To address this bottleneck, we rationally design a β-cyclodextrin-modified mixed-valent iron (Fe 2+ /Fe 3+ ) ‑aluminum hydroxide hybrid composite (CD-FeAl-HC) for efficient tetracycline (TC) removal. A unique cooperative enrichment-stabilization mechanism is realized in this structured composite: interfacial activated β-CD acts as a molecular recognition unit that rapidly pre-concentrates TC from bulk solution, while the adjacent mixed-valent Fe 2+ /Fe 3+ sites provide strong coordination binding for stable immobilization. DFT calculations further reveal that interfacial electron transfer from β-CD to FeAl-HC induces a distinct positive shift in the electrostatic potential of the β-CD cavity, converting it from an inert pocket into an electron-deficient molecular trap. Benefiting from this synergistic effect, CD-FeAl-HC delivers a competitive maximum adsorption capacity (151.99 mg/g), remarkably fast adsorption kinetics, and excellent anti-interference performance against coexisting ions and natural organic matter. Notably, the composite achieves over 90% removal efficiency for both TC and ofloxacin in mixed solution, while maintaining >90% TC removal in real water matrices (reservoir and landscape water). Furthermore, it retains more than 90% of removal efficiency after 10 consecutive adsorption-desorption cycles, demonstrating outstanding reusability. This work establishes a generalizable design strategy that integrates molecular enrichment and surface stabilization within a single hybrid material, providing a promising framework for the rational construction of high-performance adsorbents toward emerging organic pollutant remediation. Download: Download high-res image (160KB) Download: Download full-size image

Robust artificial interface combining AlF3 coating with carbon layer stimulates stable long lifespan for Na2TiV(PO4)3 in sodium storage

Xinbo Li,Qinghao Cao,Junyang Chen,Chuanpu Zhang,Qiang Ru

Dual-layer artificial interface of carbon/AlF 3 enhances conductivity and Na + transport, suppressing structural degradation. • NTVP@C/AF-1%: 184.58mAh g −1 at 0.1C, 93.66% capacity retention after 2500 cycles at 20C. • NTVP@C/AF-1% full cell: 81.88% capacity retention of after 300 cycles at 1C. The vanadium-based NASICON-type cathodes face challenges of excessive cost and capacity decay induced by structural degradation during cycling. Surface modification has been confirmed as a favorable strategy to purchase a reasonable balance between sodium storage performance and long lifespan for cathodes. A carbon/AlF 3 dual-layer artificial interface was ingeniously engineered to encapsulate the Na 2 TiV(PO 4 ) 3 cathode (NTVP). Through modulating AlF 3 coating content, the NTVP@C/AF-x% series (x = 0.5, 1, 2, 3, 5) were harvested to accelerate Na-ion diffusion and alleviate structural collapse, thereby strengthening the rate capability under high-rate conditions. Furthermore, the dual-layer artificial interface effectively reduces the polarization voltage and boosts the Na-ion diffusion coefficient. The strategy-modified NTVP@C/AF-1% cathode delivers a high specific capacity of 184.58 mAh g −1 at 0.1C, and maintains a capacity retention of 93.66% after 2500 cycles at 20C. Furthermore, the NTVP@C/AF-1% also serves as an anode, demonstrating favorable cycling durability with 91.67% capacity retention after 400 cycles at 1C. The NTVP@C/AF-1% cathode demonstrated excellent compatibility with the hard carbon anode. The assembled NTVP@C/AF-1% full cell exhibits enhanced electrochemical performance with a capacity retention of 81.88% after 300 cycles. This work demonstrates the modified interfacial structures can unlock more possibilities for the further development of NASICON-type cathodes. Download: Download high-res image (101KB) Download: Download full-size image

Regulation of myofibrillar protein gelation by epigallocatechin-3-gallate and carrageenan type: structural and conformational changes associated with gel performance

Can Luo,Yuexing Shi,Muhammad Ramzan,Handan Zhang,Dongyang Jia,Lianhong Guo,Jie Zhu

A concentration-dependent biphasic effect of EGCG on reduced-salt MP gelation was observed. • EGCG-containing MP gels at 0.3 M NaCl were better stabilized by ι-carrageenan. • S–S conformational order was reduced by κ-carrageenan at high EGCG addition. • Raman-derived S–S orderliness was closely associated with gel strength. • EGCG functionality in reduced-salt MP gels was redirected by carrageenan type. Epigallocatechin-3-gallate (EGCG) interacts with muscle proteins, but its concentration-dependent effects on reduced-salt myofibrillar protein (MP) gels and their modulation by carrageenan type remain unclear. This study investigated the effects of κ- and ι-carrageenan on the gelation, cooking loss, molecular structure, and structure–function relationships of MP gels containing 0, 2.5, 5, or 10 μmol/g EGCG. In carrageenan-free MP gels, EGCG exhibited a biphasic effect on gel strength, which peaked at 5 μmol/g (57.13 g mm) but declined at 10 μmol/g (32.61 g mm), accompanied by increased cooking loss (65.84%). Carrageenan type distinctly reshaped this response. Compared with κ-carrageenan, ι-carrageenan showed better compatibility with EGCG-containing MP gels, resulting in lower cooking loss at 10 μmol/g EGCG (59.20% vs. 65.91%) and improved network continuity. Raman and FTIR analyses showed that ι-carrageenan-containing gels exhibited a higher disulfide conformational orderliness index (0.85), together with coordinated amide-region changes including a β-sheet content of 38.8%, whereas κ-carrageenan-containing gels showed lower disulfide orderliness (0.41) and higher cooking loss. Regression analysis identified S–S conformational orderliness as the strongest predictor of gel strength (R 2  = 0.91). These findings indicate that carrageenan does not simply act as a universal gel enhancer in reduced-salt MP systems, but modulates EGCG functionality in a type-dependent manner. This work provides insight into designing reduced-salt meat protein gels using polyphenol–polysaccharide combinations. Carrageenan type directs EGCG modulation of reduced-salt myofibrillar protein gels. Download: Download high-res image (537KB) Download: Download full-size image

Constructing heterostructure by co-doping of Ta5+ and F− with carbon nanotubes to improve kinetic properties of Na3V2(PO4)3

Tao Zhou,Yanjun Chen

The advancement of Na 3 V 2 (PO 4 ) 3 has been impeded by its subpar kinetic characteristics, resulting in suboptimal electrochemical performance . In this case, a dual modification strategy involving Ta and F co-doping is employed, along with the incorporation of carbon nanotubes (CNTs), is introduced. Notably, the substitution of high-valence Ta 5+ for V 3+ ions induces an n-type doping effect, thereby increasing the density of free electrons and enhancing electrochemical performance. Moreover, Ta 5+ possesses a comparatively larger ionic radius than V 3+ , which enhances the ease of Na + transport, leading to an increased rate of ionic diffusion. Furthermore, Ta 5+ ions play a crucial role in reinforcing the crystal structure, thereby strengthening the stability of the NVP system. Importantly, during the high-temperature calcination process, the reduction of carbon results in the conversion of Ta 5+ to Ta 3+ , forming a novel conductive TaN phase through its reaction with N 2 . This TaN phase, known for its high conductivity, intercalates into the NVP bulk as interlayers, forming beneficial grain boundaries. Thanks to this unique TaN//NVP heterojunction , the migration of Na + ions is notably accelerated along the grain boundaries rather than within the NVP bulk. The introduction of F contributes to reducing the grain size of active particles, consequently shortening the pathways for Na + migration and improving kinetic properties. Moreover, the presence of carbon layers and the encapsulation of CNTs collaboratively construct a highly conductive cross-linking network, elevating both electronic conductivity and mitigating NVP particle aggregation during high-temperature sintering. Consequently, the modified NVTPF0.07/@CNTs sample exhibits outstanding performance in both half and full cells, underscoring its substantial potential for application in the field of sodium-ion batteries.