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The newly-emerged gas sensing detection of 1-octen-3-ol biomarker is expected to indirectly monitor foodborne illnesses caused by Salmonella-contaminated meat, which requires high selectivity and a ppb-concentration detection limit. Here, surface-doped ruthenium over tungsten oxide nanocubes (Ru/WO₃ NCBs) have been synthesized by a wet-chemical approach for highly selective and ppb-concentration 1-octen-3-ol sensing. As-prepared Ru/WO₃ NCBs exhibit a polycrystalline structure and consist of NCBs that have an average side length of ∼131 nm, and the Ru/WO₃ NCBs show a high sensing response toward 5 ppm 1-octen-3-ol (R_a/R_g = 406), excellent selectivity, 50 ppb detection limit, 70 % relative humidity tolerance, and 54 days stability at 220 °C. The excellent sensing performance might be attributed to the electronic and chemical sensitization of Ru, which thickens the electron depletion layer and increases adsorbed oxygen to promote interfacial electron transfer and 1-octen-3-ol oxidation. Practically, Ru/WO₃ NCBs have been integrated into a sensing device to simulate detecting 1-octen-3-ol, which has the potential for Salmonella detection in the future.

Organic nanogrids are versatile molecular hornstones and nanoplatforms of organic high-dimensional, low-entropy materials. It is urgent to construct virtual databases of organic nanomers for accelerating the discovery and performance optimization of novel 0/1/2/3-dimensional nanopolymer optoelectronic materials. In this study, we generated a comprehensive dataset of 11,224 ladder-type gridarenes, covering a wide range of chemical compositions and structural variations. A random selection of 220 small sample sets was aggregated, and fragment-level constrained density functional theory (CDFT) was employed to extract molecular descriptors. These descriptors were then used to train machine learning models with high predictive accuracy for band gap, highest occupied molecular orbital (HOMO), and lowest unoccupied molecular orbital (LUMO) energies (the coefficient of determination values of 0.94, 0.92, and 0.87, respectively). During the active learning process, 3112 representative gridarenes were iteratively selected from our 11,224-compound library, refining band-gap predictions to a mean absolute error below 0.11 eV. This process pinpointed top candidates for blue-light emission and demonstrated an accelerated, data-driven route to next-generation organic optoelectronic nanomaterials.

Accurate detection of NADH levels plays a critical role in the diagnosis and management of conditions ranging from metabolic disorders to neurodegenerative diseases such as Parkinson and Alzheimer. It also holds potential for therapeutic interventions targeting mitochondrial function and energy metabolism. Herein, we designed the miniaturized sharp-edged hyper-branched gold microneedles (Au MNDs) decorated with pencil graphitic microelectrodes (PGME) via single-step, green electrochemical deposition strategy in the absence of any redox mediators, organic solvents and enzymes, etc. The as-prepared Au microneedles demonstrate impressive direct electrocatalytic properties for NADH oxidation. Their sharp edges of the microneedles and the optimized transducers ionic mobility effectively enhance electrochemically active surface area and intrinsic charge transfer efficiency, making this electrode a powerful enzyme-mimic platform for detecting NADH. This morphology, combined with the unique surface features, fosters a highly ideal conditions for the rapid electron transfer from NADH to the Au MNDs @PGME. The nanostructures improve the mobility directly influences the speed and efficiency of electronic charge carriers, which accelerates the rate of electron transfer. This enhances the electrochemical kinetics of the system, contributing to rapid and sensitive detection of NADH. These attributes indicate that Au MNDs-modified microsensor holds great potential for high sensitivity (62.80 μA/μM cm^-2), two distinct linear ranges: 0.1-4.5 μM and 4.5-54.5 μM, fast response (<2 s), and lower LOD for the reliable NADH detection. The miniaturized microsensors had a strong ability to prevent anti-interference from sensing of NADH. Notably, the current micro sensing platform, which is based on Au MNDs @PGME, has proven to be useful in clinical diagnostics by successfully testing for NADH sensing in human serum and urine samples in biomedical application.

Wagyu beef's distinctive flavor and tenderness arise from its high levels of unsaturated intramuscular triglycerides. Although these compositional distinctions provide a unique Raman signature, extensive band overlap and background attenuation from packaging and frozen conditions hinder reliable in situ classification and constrain the interpretability of raw spectra. This study presents a label-free Raman spectroscopic and chemometric approach for authenticating Wagyu beef under realistic retail-like conditions. A supervised partial least squares discriminant analysis (PLS-DA) model was developed using spectra from unwrapped adipose tissue and evaluated with an independent validation set of frozen, plastic-wrapped samples from multiple breeds and suppliers. The model achieved 100% sample-level classification accuracy, supported by receiver operating characteristic and confusion-matrix analyses. To elucidate the molecular basis of discrimination and resolve spectral congestion, a two-stage decomposition combining singular value decomposition (SVD) and nonnegative matrix factorization (NMF) was applied, followed by nonnegative least squares (NNLS) fitting with pure triglyceride standards. The analyses yielded chemically interpretable components, revealing enrichment of unsaturated triglycerides in Wagyu beef consistent with established compositional data. To our knowledge, this is the first report applying Raman-based PLS-DA for Wagyu authentication and integrating SVD, NMF, and NNLS for molecular-level interpretation in food authentication. Overall, Raman spectroscopy integrated with interpretable spectral decomposition provides a rapid, nondestructive, and chemically transparent tool for meat authentication and quality assurance.

Chronic kidney disease (CKD) requires fast, noninvasive tools for early detection and staging that go beyond conventional serum creatinine/eGFR measurements. NAD(P)H, a key coenzyme in cellular metabolism, energy transfer, and redox signaling, is closely associated with the normal kidney function. Monitoring intracellular NAD(P)H levels offers a promising strategy for CKD assessment. Here, we present a novel dual-salt fluorescent probe (CKD-pro) for the rapid and sensitive detection of NAD(P)H. The CKD-pro is constructed from 1-methylquinolinium and naphthalene thiazolium salt units connected through vinyl linkers. Upon reduction of the quinolinium moiety by NAD(P)H, the probe converts into a donor-π-acceptor (D-π-A) architecture, resulting in a rapid fluorescence signal at 585 nm. Probe exhibits excellent analytical performance, with a linear response over 0-2 μM, a limit of detection (LOD) of 20 nM, and a response time shorter than 2 min. It also shows high selectivity and good biocompatibility, enabling real-time monitoring of NAD(P)H dynamics in G6PD-knockout cancer cells and HK-2 renal cells under hypoxia. In a clinical proof-of-concept study (midstream urine, n = 30 CKD patients and n = 10 healthy controls), the fluorescence signal from CKD-pro was significantly higher in CKD patients, showed an inverse correlation with eGFR, and successfully discriminated CKD from healthy individuals (AUC = 0.847). Moreover, the probe effectively stratified mild-to-moderate (stages 1-3) and severe (stages 4-5) CKD with an AUC of 0.915. Together, these findings establish CKD-pro as the first urine-based optical NAD(P)H probe for non-invasive CKD screening and staging, underscoring its clinical translation potential.

Cell transfection and dynamic monitoring of subsequent cellular physiological activity play a crucial role in studying gene function and regulating gene expression. However, platforms integrating cell transfection with dynamic monitoring of cellular physiological activity are rarely reported. Here, we propose a novel technology using a nanopore array platform combined with nanodrums fabricated from ultrathin graphene, which enables single-cell transfection while dynamically monitoring post-transfection changes in cellular physiological activity. In our exploration, we found that random oscillation amplitudes generated by single OCI-Ly3 cells reached up to ∼20 nm. After transfection with the ME2 gene knockdown sequence (shME2), cellular physiological activity was inhibited, and the random oscillations were suppressed, with amplitudes decreasing to < 5 nm. Our results provide a high-throughput potential and efficient approach for gene transfection and dynamic monitoring of cellular physiological activity, offering valuable insights for cell-based drug screening, cancer cell subtype classification, and other applications.

Recently, organic electrochemical transistors (OECTs) have emerged as robust platforms for chemical and biological sensing, due to their intrinsic signal amplification, biocompatibility, and low-voltage functionality. OECTs have exhibited tremendous promise for detecting small molecule metabolites (SMMs), which are crucial as biomarkers in medical diagnosis, environmental surveillance, and food quality monitoring. This review provides an in-depth analysis of recent advancements in OECT-based sensing devices for the detection of SMMs. Besides, the fundamental design concepts of OECTs, device structures, choice of materials, and functionalization techniques are studied to enhance selectivity and sensitivity. The incorporation of recognition elements-such as enzymes, aptamers, and molecularly imprinted polymers-on the gate or channel to facilitate target-specific interactions has been studied. Furthermore, the significance of channel engineering, microfluidic integration, and nanomaterial inclusion in improving device performance has also been discussed. The review highlights the main obstacles that impede the extensive development of OECTs, including baseline drift, signal instability, and selectivity. Finally, future prospects are explored, emphasizing rising trends in smart materials, micro platforms, and wearable diagnosis. This study seeks to assist researchers in creating next-generation OECT sensors designed for real-time, selective, and sensitive identification of SMMs.

The development of simple and efficient analytical methods is fundamental for controlling the levels of toxic metals in liquid samples. In the present study, it is proposed the fabrication of a microstructured substrate based on filter paper, using in situ growth method of silver nanoparticles (AgNPs) into silver microparticles (AgMPs) to enhance the LIBS emission signal in the determination of Cu(II) in different liquid samples. Initially, ascorbic acid, NaBH₄ and SnCl₂ were evaluated as reducing agents for Ag particle formation. An 8-fold improvement in the copper signal was obtained when SnCl₂ was used. The Ag particles obtained with the latter reducing agent were further grown, and the signal was enhanced up to 14-fold compared to the traditional LIBS method using unmodified filter paper. UV-Vis diffuse reflectance spectroscopy, X-ray diffraction measurements, and scanning electron microscopy (SEM) indicated efficient immobilization of both Ag nano- and microparticles on the microfibers of substrate. A calibration analytical curve for Cu(II) ions was obtained with a coefficient of determination (R²) of 0.99, a linear response from 0.2 to 1.0 mg L^-1, and LOD and LOQ of 34 and 114 μg L^-1, respectively. The signal enhancement achieved with the microstructured substrate fabricated using the in situ growth method can be attributed to the synergistic effect of the nanostructures present in the cellulosic microfibers and the surface enhancement caused by the dense layer of Ag microparticles. The developed analytical strategy was successfully applied to the determination of Cu(II) ions in fortified samples of river water, artificial urine, tea infusion, and canned tea, providing recoveries ranging from 85 to 112 %. These results indicate the effectiveness of a microstructured silver substrate for sensitive detection of metal ions at low concentrations in liquid samples.

Characterization of the triacylglycerol (TAG) composition of food oils is challenging, in particular due to the presence of isomers. The main bottleneck is the incomplete separation of isomeric TAGs in liquid chromatography coupled to mass spectrometry (LC-MS), hindering identification because of mixed fragmentation spectra. In this study, the potential of adding cyclic ion mobility spectrometry (cIMS) as an additional dimension of separation in LC-MS analysis of food oils was explored to improve TAG isomer characterization. An analytical framework was created to achieve TAG isomer characterization by combining gas chromatography-MS (GC-MS), LC-MS, and cIMS-MS. TAG standards were used to evaluate the best option(s) for TAG isomer identification: fragmentation ratios, which can only be determined from pure fragmentation spectra obtained after separation of isomers in cIMS-MS; collisional cross section (^cIMSCCS_N2) values; or a combination thereof. Fragmentation ratios from pure fragmentation spectra yielded the strongest approach for isomer identification, as some TAG isomers were too close in ^cIMSCCS_N2 for confident identification. Finally, using this framework, we identified 21 TAG isomers in sunflower and olive oils, 11 of which would not have been identified without the use of cIMS-MS. Overall, this study demonstrates the potential of the extra separation dimension provided by cIMS and its complementarity with classical GC- and LC-MS analyses.