Chinese Journal of Analytical Chemistry最新文献

Protein-small molecule interactions play an important role in the life activities of organisms. Since protein/small molecule interactions are important for elucidating the diverse uses and their mechanisms in the fields of biological life multiplicity, disease cure, drug development, etc., methods to accurately detect protein/small molecule interactions have attracted much attention. This paper reviews the recent advances in interaction detection methods based on optical, thermodynamic, chromatographic and other principles. The structural types of small molecules for which the methods are mainly suitable and the principles of method selection are discussed, and the prospects for the combined application of different methods in the field of complex small molecule drugs are also envisaged.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrotic disease with an unclear etiology and no effective treatment. This study aims to elucidate the pathogenic mechanism networks involving multiple targets and pathways in IPF. Extracts and metabolites of Astragali Radix (AR) and Angelicae Sinensis Radix (ASR), two well-known traditional Chinese medicines, have demonstrated therapeutic effects on IPF. However, the underlying mechanisms of AR and ASR remain unclear. Utilizing network pharmacology analysis, the disease targets associated with IPF were obtained from the GeneCards database and Online Mendelian Inheritance in Man (OMIM) database. Targets of AR and ASR were identified using the Traditional Chinese Medicine (TCM) Systems Pharmacology Database and Analysis Platform and Swiss Target Prediction. A proteinprotein interaction (PPI) network was subsequently constructed and analyzed using the STRING database and Cytoscape software. Gene ontology enrichment (GO) analysis and kyoto encyclopedia of genes and genomes (KEGG) analysis were conducted using DAVID. Additionally, a component-target-pathway network was employed to identify the main active components, and molecular docking was performed between these components and proteins encoded by key targets. Finally, in vitro studies were conducted based on network pharmacology. A total of 260 common targets between IPF and drug targets were identified and included in the PPI network, in which TNF, IL-6, STAT3, AKT1, VEGFA, SRC, EGFR, INS, JUN, and IL1B were predicted as key targets. These 260 targets were enriched in the PI3K-AKT signaling pathway, HIF-1 signaling pathway, TNF signaling pathway, MAPK signaling pathway, FOXO signaling pathway, and Pathways in cancer. Docking scores ranged from –4.1 to –9.5 kcal/mol, indicating a strong binding affinity between the main active compounds and key targets. In vitro studies have indeed shown that Quercetin and Magnolol can alleviate the expression of epithelial-mesenchymal transition in the A549 cells caused by IL-6. The treatment with AR and ASR resulted in a reduction of mRNA levels for key targets HIF-1α and α-SAM. Additionally, the protein expression levels of P-JAK2/ JAK2, P-STAT3/ STAT3, and α-SMA/ β-Actin were also reduced. These results support the therapeutic potential of AR and ASR in ameliorating pulmonary fibrosis and provide insight into the molecular mechanisms involved in their therapeutic effects.

The green chemistry method for analyzing changes in the concentration of substances during a reaction process is an energy-saving and interesting experimental process. In this paper, the performance of electrolysis of methylene blue (MB) in NaCl electrolyte was studied using a smartphone-based paper microzones method (PMZs), and paper microzone platform was made by discarded label stickers. The linear range spanned from 1.25 to 15 mg/L for the concentration-absorbance correspondence measured via spectrophotometry, and from 1.25 to 17.5 mg/L for the concentration-R-value correspondence measured via the PMZs method. The findings revealed that the limit of detection (LOD) value of the PMZs method was 0.494 mg/L, and the limit of quantification (LOQ) value was 1.497 mg/L. Moreover, the accuracy ranking of the measured MB electrolytic change process across different channels was as follows: Red>Grey>Green>Blue. PMZs method also showed well reliability in measuring actual dye polluted wastewater. The results demonstrate the sensitivity and precision of the PMZs method, as indicated by the low LOD and LOQ values. Additionally, the accuracy ranking provides valuable insight into the performance of the method across different color channels, shedding light on the potential applications and limitations of the PMZs technique in color-based electrochemical analyses. The electrolysis reaction led to a red-shift in the absorption characteristics of MB in NaCl electrolyte, resulting in a notable change in its light absorption properties. This information is crucial for researchers and practitioners seeking to employ the PMZs method for accurate and reliable color measurements in various scientific and industrial settings.

Water pollution is currently a major problem worldwide. Given its detrimental effects on health, Hg(II) is considered an extremely hazardous heavy metal contaminant, even at low doses. Heterocyclic compounds have been thoroughly evaluated as the chemosensor agents for Hg(II) detection. However, they suffer from poor sensitivity. In this study, we prepared two fluorescence chemosensor agents from vanillin via several steps, i.e., etherification, Claisen–Schmidt, and cyclocondensation reactions to yield N-phenyl- and N-pyridine-pyrazoline compounds. Products characterization was accomplished via spectroscopic techniques. Chalcone, N-phenyl-, and N-pyridine-pyrazoline derivatives were successfully obtained at 87.04%, 90.91%, and 91.73% yields, with limits of detection of 156,840, 65.810, and 161.011 nM, respectively. These results show that the conversion of chalcone to pyrazoline structure improved the sensitivity for Hg(II) detection at the nanomolar level, which is 2384 times lower than that for chalcone. Further spectroscopic investigations through Job's plot, Fourier-transform infrared spectroscopy, and proton-nuclear magnetic resonance analyses revealed that Hg(II) ions were chelated with two nitrogen atoms of pyrazoline. Thus, this phenomenon can explain the considerable sensitivity enhancement for Hg(II) detection. N-Phenyl-pyrazoline is the more sensitive chemosensor to Hg(II) compared with N-pyridine-pyrazoline because the more nitrogen groups in the binding site, the less selective and sensitive the compound. This finding is also supported by the higher binding constant value of N-phenyl-pyrazoline (9.416 × 10² mol⁻¹) than N-pyridine-pyrazoline (1.771 × 10² mol⁻¹). Furthermore, N-phenyl-pyrazoline can be applied in the direct quantification of Hg(II) in tap and groundwater samples with a validity parameter in a range of 80.97%–103.54%.

To elucidate the concentrations of heavy metal elements in commercially available electronic cigarettes and improve quality assessment. Inductively coupled plasma-mass spectrometry (ICP-MS) coupled to chemometrics was used to determine the concentrations of Cr, Ni, As, Cd, Sn, Sb, Hg, and Pb in the e-liquids and aerosols derived from 32 electronic cigarettes sold commercially under six brand names. The e-liquids contained: 4.858 to 274.658 (Cr), 17.292 to 3068.375 (Ni), 3.217 to 29.867 (As), 0.225 to 24.717 (Cd), 0.783 to 17.042 (Sn), 0.658 to 36.033 (Sb), 0.658 to 187.592 (Hg), and 2.458 to 17.417 (Pb) ng g⁻¹. The aerosol samples contained: 276.075 to 3333.175 (Cr), 72.908 to 1150.183 (Ni), 4.567 to 86.958 (As), 0.400 to 12.842 (Cd), 1.092 to 32.142 (Sn), 0.976 to 10.633 (Sb), 3.483 to 234.708 (Hg), 27.833 to 849.100 (Pb) ng 100 puffs⁻¹. The recovery of heavy metals ranged from 99.1% to 112.4% in the e-liquids and from 87.3% to 116.6% in the aerosols, with RSD values below 10%. Hierarchical cluster analysis grouped the e-liquids into eight clusters, and the aerosols into five, indicating differences between products within brands and between different brands. Orthogonal partial least squares discriminant analysis coupled with variable importance in projection (VIP > 1) identified As and Sb as the primary heavy metals causing differences between the e-liquids, while differences between the aerosols were caused by Hg, As, Pb, Cd, and Cr. The use of chemometric methods yields a greater depth of information that will support improvements to the quality control of e-cigarette products and the assessment of their potential risk to human health.

In this study, Co-Ni nanomaterials were in situ synthesized on carbon fiber paper substrates, termed Co-Ni paper. Scanning electron microscopy characterization demonstrates fabricated flake-like Co-Ni nanocomposites uniformly distribute on carbon fibers, forming three-dimensional continuous network structure. The fabricated sample is determined to be a mixture of Co, Ni and C elements according to energy-dispersive X-ray spectrometer analysis. Without any pretreatments, Co-Ni paper exhibits excellent electro-oxidation capabilities towards H₂O₂, such as an excellent detecting performance in a wide linear range of 0‒11.5 mM of H₂O₂, fast amperometric responses within 1 s, and a low detection limit of 2.53 μM. Along with these intriguing properties, the in situ-synthesized Co-Ni paper has a good anti-interference towards Na₂SO₄, ZnCl₂, glucose and NaCl during H₂O₂ detection. Moreover, the H₂O₂ electro-chemical sensor on Co-Ni paper also possesses excellent reproducibility, long-term stability and high mechanical stability. This Co-Ni-paper-based sensor is effective to determine H₂O₂ in blood samples, thus it is promising for electrochemical H₂O₂ sensing.

Using terephthalic acid (BDC) as the organic ligand and zirconium chloride (ZrCl₄) as the metal source, a lanthanide metal-organic framework (Tb/Zr-UiO-66) with excellent luminescence properties was successfully prepared by introducing the lanthanide ion Tb³⁺ in situ through a simple one-pot hydrothermal reaction, which was designed as an optical biosensor for 2-thiothiazolidine-4-carboxylic acid (TTCA), the urinary biomarker of human exposure to carbon disulfide (CS₂). The fabricated Tb/Zr-UiO-66 exhibits high chemical and luminescent stability, making it competent for recognizing TTCA in aqueous environments. Significantly, its luminescence intensity change shows a good linearity relationship with the concentration of TTCA in the range of 0–110 μM, with a limit of detection (LOD) as low as 0.14 μM. Meanwhile, this sensor exhibits good selectivity and anti-interference ability towards TTCA among the various coexisting components in urine (Na⁺, K⁺, NH₄⁺, SO₄²⁻, Cl ⁻, creatine, creatinine, glucose, urea, etc.), and can quickly respond to TTCA within 2 min. The analysis results of powder X-ray diffraction (PXRD), fluorescence lifetime and ultraviolet–visible (UV–vis) spectrum demonstrate that the sensing mechanism can be ascribed to the competition absorption effect between TCAA and Tb/Zr-UiO-66. This biosensor with simple synthesis, stable framework, high sensitivity and selectivity, and rapid response has potential to become a powerful tool for diagnosing diseases associated with CS₂ exposure.

Microplastics (MPs) in the atmosphere have attracted global concern due to their potential threats to human health. However, the current rapid analytical method for airborne MPs is insufficient, which hinders a comprehensive understanding of their environmental risks. In recent years, the disposable face masks have emerged as a new source of airborne MPs. There are significant knowledge gaps regarding MPs from mask, including detection methods, formation mechanisms, and environmental abundance. This study presented a novel analytical approach for the rapid detection of airborne MPs using the electromagnetic heating-pyrolysis-mass spectrometry (Eh-Py-MS). To validate this method, surgical face masks were employed as an illustrative example. The mass-related quantification of MPs was realized based on the Eh-Py-MS. By employing a conversion model of mass, size, and density, simultaneous assessment of both mass and quantity of MPs was realized. The recovery rates were in the range of 86.6%–111.6% and the precision (RSD) was 8.4%, which was sufficient for rapid quantification. Results showed that the simultaneous tracing of mass and quantity of airborne microplastics could be successfully achieved through the developed method. Furthermore, the formation mechanism of MPs in surgical masks under UV exposure was also investigated to address the knowledge gap of masks MPs. Results indicated that surgical masks could be a neglected source of airborne microplastics in the environment. This study aims to provide valuable insights for the rapid assessment of airborne MPs in the environment.

Developing an effective method for monitoring of tetracycline (TC) concentrations is extremely crucial due to its adverse effects on both ecosystems and human health. In this study, we developed a novel glutathione-protected nickel nanoclusters (GSHNiNCs) fluorescent (FL) sensing platform to detect TC. The GSHNi NCs were synthesized by a facile one-pot route with GSH as a stabilizer and ascorbic acid (AA) as reducing agent. The experimental results confirmed that the FL of GSHNiNCs was quenched in the presence of TC based on both of the inner-filter effect (IFE) and photoinduced electron transfer (PET) mechanisms to achieve high sensitivity. Under the optimal conditions, excellent linear relationships existed between the FL intensities of GSHNiNCs and the logarithmic TC concentrations in the range of 0.5–120.0 and 120.0–300.0 μM. Even in the absence of surface modification or any complex signal amplification techniques, the proposed FL sensing platform for TC detection showed a low limit of detection of 58 nM (3σ/k). Thus, this approach provides considerable simplicity, low-cost, timesaving and flexibility for the construction of a TC sensor. Most remarkably, we could selectively analyze TC in milk samples without the need for tedious or time-consuming pretreatment processes. This work expands the FL analysis platform for TC detection, and facilitates the design and development of NiNC-based FL sensors for the monitoring of antibiotics.

Chirality, also known as handedness, is one of the most widespread and intriguing properties in nature, touching upon various fields including physics, chemistry, biology, medicine and beyond. Chiral interface is the place where chirality related process occurs. The development of synthetic chiral interface not only deepens the understanding of chiral mechanism, but also provides the basis for the application of chiral phenomenon. In this review, we provide a summary of the various types of chiral interfaces, their construction methods, and the recent process of their application in chiral recognition, chiral separation, and chiral catalysis, as well as a prospect for further direction.