In the present work, we report an electrochemical sensor based on rhenium (Re) nanoparticles embedded within a double-shelled ZnMn2O4 hollow microsphere (Re@ZnMn2O4) for ultrasensitive detection of epinephrine (EP) in biofluids. The Re@ZnMn2O4 material was synthesized via a coprecipitation and annealing route, followed by a green, caffeic acid (CA)-assisted chemical reduction. Structural and morphological analyses, including spectrophotometry, confirmed the high purity, crystallinity, and integrity of the material. Electrochemical performance was evaluated using voltammetry and impedance spectroscopy. The Re@ZnMn2O4-modified electrode exhibited superior electrochemical activity attributed to its high conductivity, large surface area, abundant active sites, and efficient charge transfer enabled by the hollow architecture. EP oxidation followed a diffusion-controlled 2e-/2H+ transfer mechanism. The sensor demonstrated a broad linear detection range (0.5-1951.3 μM), a low detection limit (0.21 μM), and good sensitivity (0.282 μA μM-1 cm-2). Furthermore, it showed remarkable reproducibility, long-term stability, and strong resistance to common interferents. Its practical potential was validated by accurate EP quantification in human serum and urine, highlighting its applicability in clinical diagnostics and biomedical monitoring.

In-host bacterial evolution presents a major barrier to effective infection management, driving phenotypic adaptations such as antibiotic resistance and altered virulence. Pseudomonas aeruginosa, a key opportunistic pathogen, frequently undergoes rapid evolutionary changes during chronic lung infections, complicating diagnosis and treatment. Current strain typing via whole genome sequencing or selective culturing is costly and time-intensive, and the complex relationship between genetic variations and the resulting phenotype makes clinically relevant pathotypes difficult to identify. Here, we report a cross-reactive, glycopolymer-based fluorescent sensor array capable of directly identifying phenotypic changes related to in-host evolution in P. aeruginosa. The sensor array can accurately distinguish phenotypic variations arising from single-gene defects and discriminate clinical isolates with known differences in their evolutionary and pathoadaptive trajectories. Notably, our system is also capable of identifying P. aeruginosa isolates as distinct from other bacterial species commonly found in complex polymicrobial lung infections. Our modular platform presents an opportunity to develop sensor arrays that target carbohydrate recognition in a variety of pathogens, offering potential application as a rapid diagnostic tool to inform clinical treatment decisions based on the direct classification of phenotypic profiles.

Plant diseases threaten global food security, necessitating efficient, field-deployable diagnostics. Traditional approaches, including morphological assessments and conventional sampling methods such as swabs or multistep DNA extraction, are often unreliable in the early stages of infection when visible symptoms are absent and subsurface pathogens remain inaccessible, underscoring the need for molecular tools. Here, we present a microneedle (MN)-based diagnostic platform integrated with loop-mediated isothermal amplification (LAMP) and lateral flow assay (LFA), supported by a custom-built portable heater (LAMPbox). The MNs enable the direct extraction of plant fluids and associated pathogens, offering a rapid, simple, and efficient sampling approach. In this study, two MN types were evaluated: poly(vinyl alcohol) (PVA) and stereolithography-printed MNs fabricated from a plant-derived resin. The 3D-printed MNs exhibited superior mechanical robustness, with a displacement ratio of only 3.3% compared to 24.5% for PVA MNs, and provided an ∼12% higher DNA yield than conventional swab-based methods. Integrated with the LAMPbox, this platform enabled reliable detection of Puccinia triticina with clear differentiation between healthy and infected leaves. This work establishes 3D-printed MNs as mechanically robust and effective tools for pathogen sampling while demonstrating the feasibility of a low-cost, portable, and sustainable system for early plant disease diagnosis.

The introduction of oxygen vacancies (OVs) into metal oxide micro/nanostructures significantly enhances both catalytic performance and electrical conductivity, thereby boosting their gas-sensing capabilities. However, conventional approaches for engineering oxygen vacancies typically require specialized equipment (e.g., autoclave reactors) and extreme operational conditions (e.g., high temperature and high vacuum), posing substantial challenges for practical applications. Herein, a novel single-step laser-induced technique is developed for fabricating CuOx-based room-temperature acetone sensors under ambient conditions. The technique enables mask-free fabrication of tunable sensing films spanning morphologies from porous networks to nanospheres by precisely modulating the film thickness. Furthermore, oxygen-vacancy self-doping is inherently coupled with the micro/nanostructure growth mechanism, bypassing conventional postsynthesis treatments while preserving process simplicity. The as-prepared CuOx gas sensors with distinct morphologies manifest exceptional room-temperature acetone sensing with a wide response range spanning 0.1-10 ppm. Comparative analysis of nanosphere-based gas sensors conclusively demonstrates that oxygen vacancies constitute a key structural determinant, enabling room-temperature sensing capability in CuOx-based sensors. Moreover, both gas sensors exhibit outstanding selectivity toward acetone against common interferents (NO2, H2, CO2, and CO) and a low detection limit, highlighting their potential for trace acetone gas detection applications.

Nucleic acid detection plays an important role in pathogen monitoring and disease diagnosis. CRISPR one-pot assays combined with isothermal amplification are emerging as promising point-of-care technologies that simplify workflows while increasing sensitivity and specificity. However, the incompatibility inherent in the one-pot reaction of isothermal amplification and CRISPR detection limits their practical application. This review comprehensively analyzes diverse advanced one-pot CRISPR-based isothermal amplification strategies developed to overcome this fundamental challenge. These strategies primarily encompass physical separation strategies (utilizing lid-bottom, internal ledge, nested tube, and membrane approaches), phase separation strategies (employing glycerol, sucrose, and gel matrices), reaction system optimization strategies (fine-tuning reaction parameters and incorporating specialized additives), non-PAM and suboptimal PAM strategies, improved Cas enzyme strategies (enhanced Cas12 and Cas13 variants), light-controlled approaches (PC-oligonucleotides, NPOM-dt modification, and acylation modification), and microfluidic chip integration strategies (centrifugal microfluidic chips, droplet microfluidic chips, and microarray chips). These methodological approaches have achieved important advances in simplifying operational processes, enhancing sensitivity, shortening detection cycles, and minimizing cross-contamination risks. The review further synthesizes critical insights regarding current opportunities, technical challenges, and future directions for one-pot CRISPR-based isothermal amplification technologies in nucleic acid detection, providing valuable guidance for researchers and practitioners in this evolving field.

Extracellular vesicles (EVs), which carry a variety of molecules such as proteins and nucleic acids, have great potential for broad application in liquid biopsy. However, achieving highly sensitive detection of biomarkers within EVs remains a significant challenge. The emergence of CRISPR/Cas systems─adaptive immune mechanisms found in bacteria and archaea that defend against foreign genetic elements─offers new opportunities to address this issue through powerful nucleic acid recognition and cleavage capabilities. Compared to other EV detection techniques, CRISPR/Cas-based biosensors exhibit superior sensitivity, specificity, and operational efficiency, making them a compelling platform for clinical translation. Thus, to promote the application of EVs in disease diagnosis, disease monitoring, and therapeutic evaluation, this review focuses on the state-of-the-art CRISPR/Cas systems (specifically CRISPR/Cas9, CRISPR/Cas12, CRISPR/Cas13, and CRISPR/Cas14) as well as the latest applications of CRISPR/Cas-based EV detection techniques.

Lateral flow assays (LFAs) are point-of-care devices that are known for their affordability, speed, and simplicity. However, LFA sensitivity is often limited by the need for fast associative rates between the assay components. This work presents a strategy toward reducing the demand for fast test line associative kinetics via a "capture-and-release" approach. Using HER2 protein as a model biomarker system, this methodology─termed the "AmpliFold" approach─involves the initial sequestration of analyte-bound complexes, which undergo triggered release and are rebound, using high-affinity hapten interactions, resulting in enhanced signal-to-noise detection. Using anti-HER2 Fab fragments modified with cleavable biotin linkers to achieve triggered release, the importance of linker length and bioconjugation strategy on the efficiency of analyte-bound complex release is described. Cleavable Fab fragment conjugates were combined with 'dual-affinity' gold nanoparticles (AuNPs) highly decorated with fluorescein-tagged anti-HER2 antibodies to facilitate signal amplification. The utility of the AmpliFold approach is demonstrated by titrating capture receptor density to modulate the signal distribution across test lines. Larger capture areas in the AmpliFold approach were shown to overcome poor capture kinetics associated with low receptor densities, achieving up to a 16-fold improvement in LFA sensitivity. The AmpliFold approach was further shown to address the poor diffusivity and surface binding kinetics of large nanoparticles in LFA systems. Using high capture receptor densities and a 150 nm AuNP example, a 12-fold sensitivity enhancement was achieved when using AmpliFold to detect the target analyte spiked into both buffer and human serum samples. Incorporated into a folding "two-strip" LFA design and performed via a multistep (capture, wash, and linker cleavage) workflow, the AmpliFold approach represents a proof-of-concept strategy that utilizes established protein modification chemistries to provide a rapid (<30 min), equipment-free, and tractable route toward enhancing LFA kinetics and sensitivity.

Exosomes that can cross the blood-brain barrier are promising biomarkers for glioma diagnosis, yet highly specific and sensitive detection of glioma-derived exosomes remains a challenge. Herein, a strategy of "proximity effect-mediated DNA self-assembly" has been proposed to achieve highly specific, sensitive, and flexible detection of glioma-derived exosomes. Exosomes are separated and enriched by CD63 aptamer-modified nanomagnetic beads; a pair of proximity probes simultaneously binds to PDPN and EGFR on the surface of exosomes, which will induce proximity effect-mediated DNA self-assembly with linker probes and the subsequent invertase-labeled signal amplification probes, thus converting one target exosome in the presence of multiple invertases. Benefiting from the dual signal amplification from nucleic acid self-assembly and enzymatic reaction, highly sensitive and flexible detection of glioma-derived exosomes can be achieved by using a portable blood glucose meter, with a limit of detection of 3 × 104 particles/mL. Of note, the combined detection of multiple exosomal surface markers (CD63/PDPN/EGFR) based on proximity hybridization significantly improves the specificity of glioma-derived exosome detection, enabling efficient discrimination of glioma cells from normal microglia and various other tumor cells. Furthermore, the level of CD63/PDPN/EGFR-positive exosomes in glioma patients was significantly higher than that of healthy subjects (P < 0.0001); compared with the CD63/PDPN- and CD63/EGFR-positive exosomes (AUCs of 0.852 and 0.895), the detection of CD63/PDPN/EGFR-based exosomes provides a remarkably accurate diagnosis of glioma (AUC of 0.98). Additionally, this strategy can be easily extended to the detection of other disease-derived exosomes just by replacing the corresponding recognition units.

To understand the gas-sensing mechanism of COFs and explore an effective modulation way to regulate their sensing properties, the adsorption and sensing behaviors of NO2, NO, SO2, O2, H2O, CO2, H2S, CO, N2, and NH3 gas molecules on the surface of pristine and n-doped (Na-adsorption) Tr-Th COFs are explored theoretically with first-principles calculations in this work. Attributed to the lowest unoccupied molecular orbital (LUMO) energy level of NO2, the adsorption of NO2 on Tr-Th leads to a larger increase in carrier concentration increment (n = 1.79 × 1012 to 6.26 × 1010 cm-2) and a greater work function shift (ΔΦ = 0.178 eV) compared to other gases, which suggest that Tr-Th is a highly promising material for NO2 sensing applications. n-Type doping elevates the Fermi level of COFs, resulting in a greater carrier concentration increment (n = 1.83 × 1012 cm-2 ∼ 2.52 × 1012 cm-2) and a larger work function shift (ΔΦ = 0.08 eV ∼ 0.30 eV) upon exposure to NO2, NO, SO2, or O2 compared to other gases. It means that apart from NO2, NO, SO2, and O2 gases will also trap electrons in n-doped Tr-Th COFs, increase the electrical resistance dramatically, and then quench the source leakage current of the COFs-FET gas sensor. Our study provides more detailed information about the gas-sensing mechanism of COFs and highlights the key role that surface doping strategy plays in regulating the gas adsorption and selection behaviors for its practical gas sensor applications.