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The extensive application of glyphosate (GLY) in modern agriculture has raised increasing concerns regarding environmental contamination and food safety. In this work, a dual-mode hydrogel sensing platform was constructed based on Ce/Zr-MOF with intrinsic peroxidase-like activity. The synthesized Ce/Zr-MOF efficiently catalyzed the oxidation of TMB into blue oxTMB, enabling colorimetric detection while simultaneously generating a photothermal response. Notably, GLY strongly coordinated with the Ce³⁺/Zr⁴⁺ active centers, effectively inhibiting the catalytic reaction and leading to concentration-dependent attenuation of both color intensity and photothermal heating. Owing to this inhibition mechanism, the hydrogel sensor achieved dual-mode detection of GLY over a wide linear range of 0-500 μM, with low detection limits of 0.13 μM (colorimetric) and 0.08 μM (photothermal). This platform also demonstrates excellent selectivity and long-term stability. Furthermore, a deep learning-based dual-modal concentration prediction network (DMCPNet) was developed to enable rapid and accurate determination of GLY concentrations. The proposed strategy offers reliable on-site detection of GLY and demonstrates the potential of multifunctional hydrogel sensors for environmental and food safety monitoring.

With the rapid development of wearable health monitoring technology, real-time, non-invasive, and multi-modal physiological signal acquisition has become a key requirement for improving disease warning and health management levels. Here, we demonstrate a dual-mode wearable health monitoring system based on functionalized hydrogel, which realizes accurate detection of ionic concentrations in human sweat and stable extraction of pulse wave signals. A porous hydrogel sweat sensing platform based on polyvinyl alcohol (PVA) is designed to solve the problems of low electrolyte penetration efficiency and skin irritation during sweat detection. Combined with electrodes modified with polypyrrole (Ppy) and ionophores, electrochemical sensors capable of measuring the concentrations of sodium (Na⁺) and chloride (Cl^-) ions are constructed. The sensitivity of the sensors is close to theoretical value of the Nernst equation, exhibiting good selectivity, repeatability, long-term stability, and reliability. In order to capture weak pulse signals, we have developed a highly sensitive pulse sensor based on PVA/poly (ethylene glycol) (PVA/PEG) dual network conductive hydrogel. Furthermore, a pyramid array structure is designed to develop piezoresistive flexible pressure sensor. This sensor features high sensitivity, rapid response/recovery time (25.0 ms/17.5 ms), low detection limit (7.9 Pa), and long-term stability, capable of accurately detecting arterial pulse waves and heart rate under various physiological conditions. A matching smartphone-integrated monitoring system is then developed, which supports dual channel ion detection, pulse waveform analysis and wireless data transmission. This study provides an effective solution for personalized health monitoring, and shows the application potential of functional hydrogel in the field of wearable health monitoring.

The exploration of new kinds of materials with novel sensing mechanisms for photoelectrochemical (PEC) analysis are crucial for advancing efficient PEC detection. This study demonstrated that cysteine (Cys) induced surface polarization effect (SPE) on the surface of the environmentally friendly layered bismuth-based semiconductor material, i.e., BiOCOOH. Based on this finding, we established a detection system for small molecules dehydroisoandrosterone-3-sulfate (DIS) and bisphenol A (BPA) by integrating the SPE sensing mechanism with the aptamer recognition reaction. That was, the Cys bound to the BiOCOOH surface via its thiol group through its interaction with Bi(III) ions, and generated the SPE with a surface polarization electric field, thereby enhancing photocurrent. This detection system demonstrated commendable performance in DIS and BPA analysis, with a linear detection range of 0.1-250 μM for DIS and a detection limit as low as 14 nM. For BPA analysis, the linear range spanned 0.01-100 μM with a detection limit as low as 1.4 nM. This study validates the SPE on extensible semiconductors/polar molecules with potentially extended applications across diverse fields, including multifunctional PEC analysis and the development of highly efficient photocatalysts, photoelectrocatalysts, and solar cells.

The research presents the development of an ultrasensitive chemiluminescent immunoassay (CLIA) for detecting the Alzheimer's disease (AD) biomarker amyloid-β (Aβ) 1-40 in plasma, utilizing novel monoclonal antibodies and an innovative soluble macromolecular signal amplification carrier, Ficoll400-Streptavidin (Ficoll400-SA) conjugates. The study successfully generated two high-affinity monoclonal antibodies (KD ≈ 10^-10 M), designated 2F10 and 12H6, which are epitope-specific and target distinct N-terminal and C-terminal regions of Aβ1-40. These antibodies demonstrated exceptional specificity, exhibiting minimal cross-reactivity (<0.5%) with closely related isoforms like Aβ1-42. The Ficoll400-SA carrier, formed by conjugating multiple streptavidin molecules to the Ficoll400 backbone and further crosslinking, enabled substantial signal amplification by facilitating rapid, homogeneous reactions and high-density enzyme loading capacity. Optimization of assay conditions demonstrated a 13-fold signal enhancement compared to conventional streptavidin-horseradish peroxidase (SA-HRP) systems, achieving an ultra-low detection limit of 0.28 pg mL^-1 and a broad dynamic range (0.54-1000 pg mL^-1). The assay exhibited excellent precision (CV < 8%), robust stability under accelerated and onboard conditions, and outstanding specificity with negligible cross-reactivity. Clinical validation against a commercial Aβ1-40 assay using human plasma samples showed a remarkable correlation (Spearman's ρ = 0.99) and no systematic bias, confirming the assay's accuracy and translational potential. Overall, this integrated approach offers a robust, cost-effective, and ultrasensitive platform for Aβ1-40 quantification, advancing blood-based AD diagnostics and demonstrating the versatility of soluble macromolecular carriers in immunoassay signal amplification.

Highly efficient and accurate analysis of ultra-trace anthropogenic ²³⁶U in the presence of natural uranium isotopes is essential for nuclear forensics and environmental monitoring. In this study, we developed an integrated analytical method for the determination of ²³⁴U, ²³⁵U, ²³⁶U, and ²³⁸U by combining highly automated sample preparation with highly sensitive ICP-MS/MS detection. Automated total dissolution was employed to ensure complete extraction of both endogenous and exogenous uranium from solid matrices, while reproducible chemical separation was achieved using an automated platform equipped with regenerable UTEVA resin. This optimized procedure yielded exceptionally low operational blanks for ²³⁶U at femtogram level. Moreover, the final eluent volume was minimized to 1.5 mL, allowing direct introduction into the ICP-MS/MS. By utilizing a membrane desolvation sample introduction system and a novel mass-shift mode (targeting UO₂⁺ species), the ICP-MS/MS sensitivity exceeded 4.1 × 10⁶ cps/ppb, while the ²³⁵UH ⁺ interference formation rate for ²³⁶U was suppressed to 7.1 × 10^-10. Consequently, the achieved detection limits for ²³⁶U and the ²³⁶U/²³⁸U atom ratio were as low as 1.85 fg/g and 5 × 10^-12, respectively. This method was successfully applied to determine the uranium isotopic composition in sediments from the adjacent sea area of the Daya Bay Nuclear Power Plant. These results demonstrate that the proposed method provides a robust and high-throughput solution for accurately quantifying of ultra-trace ²³⁶U in environmental samples, such as those impacted by the global fallout.

This work presents AptaStick, a stereolithography 3D-printed stir-stick device functionalized with a bisphenol A (BPA)-specific aptamer for selective extraction from soft drinks. For this purpose, several geometries were evaluated to optimize extraction performance, with a star-shaped design providing the highest extraction efficiency and reproducibility. Under optimized conditions, BPA retention reached 99%, and quantitative elution was achieved within 15 min using acetonitrile/phosphate-buffered saline containing adenosine triphosphate. The method provided a linear response between 2.5 and 2000 μg L^-1 (r² = 0.996), with limits of detection and quantification of 94 and 313 ng L^-1, respectively. Intra- and inter-device precision were 1.1% and 10.7% (relative standard deviation), and the device was reusable for at least four times. Application to commercial soft drinks yielded BPA recoveries from 87.8 to 99.5%. The proposed platform combines additive manufacturing versatility with aptamer selectivity, offering a simple, reusable, and sustainable alternative for selective extraction of BPA, a relevant endocrine-disrupting compound, in beverage analysis.