Analytical and Bioanalytical Chemistry最新文献

Fusion genes are a series of typical tumor biomarkers that can induce dysregulated gene expression and generate oncogenic proteins, both of which contribute to malignant transformation. Consequently, their detection is crucial for early cancer diagnosis, treatment selection, and prognostic evaluation. However, the existing fusion gene detection techniques remain constrained by time-consuming protocols, labor-intensive sample processing, and dependence on sophisticated instrumentation. To overcome these challenges, we present a rapid and portable photothermal biosensing platform utilizing DNA sandwich nanozymes (DSNs). The DSN integrates dual functionalities: a highly specific recognition probe for the BCR-ABL fusion gene, and a peroxidase-mimetic nanozyme that catalyzes the 3,3',5,5'-tetramethylbenzidine (TMB)-H₂O₂) redox reaction, producing both visible colorimetric signals and quantifiable photothermal effects. This strategy enables sensitive detection of the BCR-ABL fusion gene, providing a valuable tool for the early diagnosis and minimal residual disease monitoring of chronic myeloid leukemia.

Adiponectin serves as a critical biomarker for metabolic disorders, with its concentration in human plasma providing predictive value for the risk of prediabetes. In this work, we report a rapid and reliable electrochemical immunosensor designed for point-of-care testing of adiponectin. The immunosensor was fabricated using a gold-sputtered silver screen-printed electrode as the substrate, on which sulfhydrylated antibodies were directly immobilized via Au-S covalent bonding. The fabrication process was characterized and optimized using electrochemical impedance spectroscopy and differential pulse voltammetry. Under optimal conditions, the proposed immunosensor exhibited a wide linear range (0.3-15 μg/mL) with a detection limit of 0.15 μg/mL. It also demonstrated excellent reproducibility and high selectivity for adiponectin detection. Additionally, the proposed immunosensor can be fabricated within 1.5 h and enables accurate quantification in human plasma within 15 min. The practical applicability of the sensor was validated through analysis of human plasma samples, and the comparison results with commercial ELISA kit are satisfactory.

Per- and polyfluoroalkyl substances (PFAS) continue to increase in concentration and prevalence in the environment due to the creation of emerging PFAS and the lack of breakdown of legacy compounds. PFAS are known to both bioaccumulate and biomagnify; therefore, species higher on the food chain, such as marine mammals, are highly exposed to these chemicals. Although studies suggest that considerable maternal transfer of persistent organic pollutants occurs via lactation, data are still lacking on the temporal trends associated with PFAS exposure. In this study, we first optimized the extraction for PFAS from 5 and 1 mL of goat's milk using a QuEChERS extraction method to account for precious breast milk samples that are often only available in small volumes. We then utilized a set of dolphin breastmilk samples from an individual mother across a 2-year lactation period to evaluate longitudinal trends in PFAS concentrations and profiles. Thirty PFAS were detected using a multidimensional platform combining liquid chromatography, ion mobility spectrometry, and mass spectrometry (LC-IMS-MS), and of these, 20 PFAS were detected continuously across the nursing window of 103-706 days. Quantitative analysis using LC-IMS-MS specifically showed concentrations of perfluorooctanesulfonic acid (PFOS) alone surpass weekly intake recommendations, allometrically scaled to dolphins, from the European Food Safety Authority and Food Standards Australia New Zealand by more than 25-fold. PFOS, however, decreased slightly over time, possibly due to transfer from feedings. Suspect screening and non-targeted analysis also identified 12 compounds including 2 long-chained perfluorosulfonic acids not traditionally evaluated in targeted analyses, as well as the PFOS precursors, perfluoroethylcyclohexane sulfonate (PFECHS) and 2-(N-ethylperfluorooctanesulfonamido) ethyl phosphate (SAmPAP). This study therefore suggests that breastmilk is a major contributor to early-life PFAS exposure for mammals, particularly to long-chained PFAS.

This study evaluated the potential of the diffusive gradients in thin films (DGT) technique to assess radiogenic strontium (Sr) and lead (Pb) isotope signatures in bioavailable soil fractions as a proxy for plant uptake. Concentrations (c_DGT) and isotope ratios of Sr (⁸⁷Sr/⁸⁶Sr) and Pb (²⁰⁷Pb/²⁰⁶Pb, ²⁰⁸Pb/²⁰⁶Pb, ²⁰⁶Pb/²⁰⁴Pb) assessed by DGT (TK100, Chelex), along with extractable (NH₄NO₃, NH₄OAc, EDTA) and total Sr and Pb mass fractions and isotope ratios, were compared to those in Lactuca sativa L. (lettuce), Triticum aestivum L. (wheat), and Raphanus sativus L. (radish) grown on five geochemically distinct soils. Relative to conventional soil extraction, DGT significantly reduced matrix loads, facilitating isotope ratio measurements by multi-collector inductively coupled plasma mass spectrometry. DGT-labile Sr and Pb concentrations and isotope ratios reflected soil-specific geochemical signatures, allowing for clear differentiation among soils. Importantly, DGT-labile isotope ratios closely matched those in plant tissues across soils and species within analytical uncertainty, demonstrating that DGT captures the isotopically relevant bioavailable Sr and Pb pool without inducing significant mass-dependent isotopic fractionation. These findings establish DGT as a practical tool for bioavailable multi-isotope tracing with strong potential for applications in environmental forensics, food authentication, and archaeological provenance research.

Lactose intolerance is common, so accurate detection of lactose in supplements and pharmaceuticals is critical. We validated an ultra-high performance liquid chromatography-tandem mass spectrometry (U-HPLC-MS/MS) method with high sensitivity and specificity for trace lactose in products labeled "lactose-free." The workflow mitigates matrix effects through solid-phase extraction and filtration and explicitly accounts for α/β mutarotation to ensure correct identification and quantification. Validation per ISO and ICH Q2 confirmed robustness and performance superior to enzymatic/colorimetric assays for quality control and regulatory compliance. The method achieved excellent linearity (R² > 0.995) over 0.05-10 ppm, recoveries of 95-105%, precision with RSD < 2%, LOQ 0.05 ppm, and matrix effect < 15%. These results enable reliable verification of "lactose-free" claims across diverse matrices, reducing false positives, enhancing reproducibility, and improving labeling transparency.

Chemical identification of adhesive remains on prehistoric stone tools is of great interest for archaeologists, as the residues contain interesting information on tool use and the exploitation of natural resources by hominins. Adhesives were used to form a wrapping around the stone tool to protect the hand from the sharp edges and improve grip, or to secure a handle out of organic material to the stone tool. This invention, of adding a handle to a stone tool, marks a fundamental change in prehistoric technology. Adhesives can be manufactured from readily available exudates, like pine resin, but could also be man-made, in the case of birch tar that is obtained by dry distillation of birch bark. The glueing properties of the adhesives could be enhanced with the addition of an additive (e.g. charcoal, ochre, beeswax). Given that adhesive manufacture is considered to indicate planning abilities and complex thought, its identification in archaeological assemblages is important for understanding the evolution of human cognition. However, given long-term burial, organic residues on stone tools are generally significantly degraded, which raises numerous chemical challenges and interpretative difficulties that need to be tackled through close collaboration between archaeologists and chemists. Without this interaction between two vastly different research fields, studies can suffer from an overinterpretation of analytical data or a lack of understanding of the archaeological context. This review discusses the main pitfalls encountered in the chemical analysis of prehistoric adhesives and offers analytical recommendations to avoid them. Applying the analytical practices as proposed here will increase the reliability and credibility of the analytical results and allow a strong chemical foundation for the archaeological interpretations. The main focus is on the use of gas chromatography-mass spectrometry for the chemical identification of prehistoric adhesives; however, other commonly used analytical techniques are also briefly discussed.

Amyloid-beta (Aβ) oligomers are key contributors to the pathology and progression of Alzheimer's disease (AD), making their characterization essential for understanding aggregation processes and developing potential therapeutic strategies. This study provides a systematic framework for analyzing Aβ(1-42) oligomers in vitro using cyclic ion mobility-mass spectrometry (cIMS). Compared to previous generations of traveling wave ion mobility (TWIM) devices, the cIMS platform offers superior resolution through its scalable ion mobility path length. However, the multistage character of the cIMS platform requires thorough investigation of parameters affecting oligomer transmission and activation to ensure reliable analysis of labile and dynamic systems such as Aβ oligomers. Our findings highlight the critical influence of cone voltage (CV) on in-source ion activation, subsequent structural changes, and oligomer detection. By balancing CV, we achieved detection of a broad range of oligomeric species while limiting their activation and maximizing signal intensity. Moreover, we present the first comprehensive set of optimized ion optics and ion mobility parameters that enable effective transmission and separation of oligomer Aβ(1-42) ions. Using the optimized method, we successfully detected a spectrum of Aβ(1-42) oligomers ranging from dimers to dodecamers. Additionally, the method was applied in collision-induced unfolding experiments, revealing size-dependent conformational transitions proving its applicability. This optimized cIMS methodology establishes a foundation for future studies on Aβ(1-42) aggregation mechanisms, AD pathogenesis, and therapeutic applications. Furthermore, our results offer valuable insights into cIMS instrument tuning, with potential applications in the analysis of other complex biological systems.

The accurate and rapid detection of fluoroquinolone antibiotics (FQs) is crucial, yet their structural homology often leads to cross-reactivity that compromise accuracy. Herein, we designed a poly(3,4-ethylenedioxythiophene) doped with a poly(styrenesulfonate) (PEDOT:PSS)-based dual-channel organic electrochemical transistor (OECT) array on a flexible, low-cost polyimide substrate. By leveraging the synergistic catalysis of single-walled carbon nanotubes (SWCNTs) and gold nanoparticles (AuNPs), effective discrimination of three FQs was achieved using gate electrodes modified with only two Nafion/SWCNTs/AuNPs composites, differing solely in AuNP mass fraction-this significantly simplifies fabrication for an electronic tongue system (ETS). Aided by principal component analysis (PCA), the system discriminates and quantifies ofloxacin (OFL), levofloxacin (LEV), and ciprofloxacin (CIP) across a wide concentration range of 0.4-1000 μM, with limits of detection (LODs) of 0.32-0.40 μM, while exhibiting excellent selectivity, anti-interference, consistency, stability, and rapid response. The comprehensive performance of this platform establishes a practical foundation for portable FQ sensing in environmental and clinical applications.