Multimodal detection significantly enhanced detection accuracy in complex biological matrices. In this work, a high-efficiency multimodal biosensor is proposed based on multifunctional SnO2/SnS2/CdSe QDs heterojunction and CuO nanoenzyme-regulating synergistic strategy, which achieves ultra-sensitive and specific detection of breast cancer-related BRCA1 gene. A high-performance photoelectrochemical (PEC) SnO2/SnS2/CdSe QDs heterojunction was constructed for the first time, which effectively enhances the light absorption capability and photogenerated charge separation efficiency. The heterojunction yields a PEC signal approximately 3.75-fold higher than that of pure SnO2/SnS2 and 11.3-fold higher than that of CdSe QDs, realizing stable PEC and electrochemiluminescence (ECL) dual signals. Notably, CuO nanoenzyme with intrinsic oxidase-like activity are introduced onto the sensing interface through target-induced amplification strategies, serving as multifunctional signal regulatory units. The CuO nanoenzyme can not only catalyze the oxidation of ascorbic acid but also trigger the ECL resonance energy transfer effect. This dual functionality enables the simultaneous "shutdown" of PEC and ECL signals and "activation" of fluorescence signals, constructing a self-verifiable triple-modal sensing platform for BRCA1 detection. The developed biosensor has been successfully applied to the quantitative detection of BRCA1 in human serum samples. This report offered a promising and versatile platform for early clinical diagnosis of breast cancer and detection of other important disease biomarkers.

The monitoring of metabolic biomarkers is currently undergoing a radical change from traditional centralized laboratory standards to decentralized point-of-care testing, particularly in the management of metabolic disorders, such as gout, and renal dysfunction. This review explores next-generation functionalized nanocomposites such as metal-organic frameworks, two-dimensional (2D) transition-metal carbides, nitrides, and carbonitrides (MXenes) and Single-Atom Nanozymes (SANs) which function as sensitive elements in sensing platforms for biomarkers detection and serve as robust, non-enzymatic mimics to address the stability challenges associated with natural enzymes. Hydrothermal and green co-precipitation methods are strategic routes to fabrication, with enhanced scalability and catalytic activity. Representative analytical benchmarks demonstrate the superior performance of these platforms for metabolic biomarkers detection achieving a picomolar limit of detection (LOD) of 102 pM for Ag-Fe2O3@PAn composites and an ultra-trace fluorescence LOD of 15 pM for tetrakis(4-carboxyphenyl)porphyrin (TCPP)-Zn0.1Co2O4 nanorods. In addition, a Nitrogen-coordinated Cobalt Single-Atom/Graphene-based Nanozyme (A-Co-NG) exhibits an extensively linear range of up to 41 950 µM with a 33 µM LOD. The review emphasizes novel biomimetic engineering approaches designed to address ongoing real-world issues, including biofouling and the interference caused by the overlapping signals from ascorbic acid and dopamine. The ingenuity and adaptability of these materials in wearable formats and applications, such as smart diapers and smartphone-assisted colorimetric sensors, offers a non-invasive roadmap for continuous real-time monitoring of metabolic processes and personalized health care. This review offers a comprehensive survey of the technological landscape for metabolic biomarkers measurements, transitioning from centralized laboratory diagnostics to decentralized point-of-care testing (POCT). It presents sophisticated sensing systems that employ highly sensitive sensors for the instantaneous identification of purine-based metabolic biomarkers, indicating a notable shift in technological advancements and their implications for human interaction. Furthermore, the review examines significant obstacles that impact the effectiveness of these technologies, limiting their practical use in real-world situations.

Antibiotic-resistant bacteria (ARB) and their genes (ARGs) pose a significant risk to public health and the ecosystem. Conventional water disinfection efficiently eliminates pathogens, however, it requires intensive chemical consumption but inefficiently removes ARGs. Herein, we propose an on-demand electrochemical platform that simultaneously eliminate both ARB and ARGs with in-situ generated hydroxyl radicals (·OH) without additional chemical inputs. Single-atom copper catalysts with CuN4 coordination structure (SA-CuN4/NC) are precisely tuned to directly convert oxygen into controllable ·OH via three-electron oxygen reduction reaction (3e[-] ORR). Operando X-ray adsorption near-edge spectroscopy reveals a potential-driven self-reconstruction of single-atom Cu sites to optimize ·OH concentration. Specially, the preferentially adsorbed H[+] onto the adjacent N atoms promotes the breaking of Cu-N bonds to form stable Cu2-CuN2 cluster as a genuine active site. As expected, the SA-CuN4/NC with moderate ·OH (~11.5 μM) exhibits ultra-fast degradation of E. coli HT115, accomplishing an ~ 8 log removal within 1 min and a complete elimination of ARGs in 30 min. Excess ·OH (~47.9 μM) triggers bacterial aggregation which compromises bacterial inactivation. These findings demonstrate that 3e[-] ORR is a sustainable and effective strategy to obtain fast and complete water disinfection, preventing environmental spread of ARGs.

Ultrasound-triggered microbubble destruction (UTMD), a non-invasive technique, has been proposed as a promising means of improving the efficacy of radiotherapy against glioblastoma (GBM); however, the underlying mechanisms remain to be fully clarified. Here, UTMD was shown to induce ferroptosis, an iron-dependent form of regulated cell death, in ionizing radiation (IR)-treated GL261 and 1016B cells, as evidenced by decreased cell viability, glutathione, and glutathione peroxidase 4 levels, and increased total reactive oxygen species (ROS), lipid ROS, iron/Fe[2+], malondialdehyde contents, acyl-CoA synthetase long-chain family member 4 expression and cell death. Suppression of ferroptosis by ferrostatin-1 or deferoxamine abolished UTMD-induced radiosensitization in GBM cells, whereas blockade of apoptosis, autophagy, or necroptosis showed no significant effect. Conversely, induction of ferroptosis using erastin, RAS-selective lethal 3, and ferric ammonium citrate further promoted UTMD-mediated radiosensitivity of GBM cells. Mechanistically, UTMD markedly increased transferrin receptor 1 (TFR1) expression in IR-exposed GBM cells. TFR1 downregulation reversed UTMD-caused increase of intracellular Fe[2+], subsequently inhibiting UTMD-induced ferroptosis and radiosensitivity of GBM cells, which were augmented by TFR1 overexpression. In GBM-bearing C57BL/6J and NOD-SCID mouse models, UTMD similarly upregulated TFR1 expression, triggered ferroptosis, and sensitized tumors to IR, and these effects were reversed by TFR1 knockdown. In conclusion, UTMD promoted the radiosensitivity of GBM partially by induction of TFR1-mediated ferroptosis, providing novel insights into the mechanism underlying UTMD-mediated radiosensitization.

Accurate detection of acetaminophen (AP) in human serum is essential to ensure clinical safety. Herein, an electrochemical detection platform was developed by modifying a glassy carbon electrode (GCE) with β-CD, NADH, and MoS2, which produced triple synergistic signal amplification to achieve a nearly 2-fold cooperative amplification effect. The modification process of β-CD/NADH/MoS2/GCE was systematically verified by SEM, XPS, FT-IR and BET. The electrooxidation of AP on the electrode was confirmed to involve 2 electrons and 2 protons via density functional theory (DFT) calculations. Evaluated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), the platform exhibited an ultra-wide linear range (1.00-3000.00 μM), an extremely low limit of detection (100.00 nM), excellent stability and anti-interference ability. Its recovery rate in actual serum samples was 92.14%-106.19%, showing superior detection performance to UV-Vis spectroscopy and fluorescence methods, and this simple, low-cost platform has significant practical value for clinical AP detection.

As a critical biomarker for early-stage tumor diagnosis, miRNA-21 poses significant challenges for colorimetric detection due to its ultra-low physiological abundance and high sequence homology. In this study, a multi-stage cascade amplification sensing platform was engineered by integrating an entropy-driven molecular circuit with a heterogeneous nanozyme catalytic network. The platform utilizes Catalytic Hairpin Assembly (CHA) for initial signal transduction, coupled with a CRISPR-Cas12a positive feedback self-cycling system to achieve exponential signal amplification. At the signal output interface, Au@Cu2O core-shell nanocomposites, synthesized via epitaxial growth, exhibit significantly enhanced peroxidase-like activity through interfacial electronic coupling. Experimental results demonstrate a limit of detection (LOD) as low as 1.39 fM, with the capacity to precisely discriminate between serum samples from lung cancer patients and healthy individuals.

Current methods for enzymatic activity assays achieve high sensitivity but require a long assay time, restricting their application in rapid clinical diagnostics. Herein, an ultrarapid and ultrasensitive dual-mode biosensing platform was developed by integrating a high-frequency quartz crystal microbalance (HFQCM, 100 MHz) with a photocurrent polarity switching photoelectrochemical (PEC) strategy, based on Cu2+-triggered sodium alginate (SA) gelation. The platform adopted a universal design where caspase-3 served as a model enzyme to demonstrate its analytical performance. First, a magnetic probe, Fe3O4@AuNPs-peptide-[CuO]n, was synthesized. In the presence of caspase-3, the peptide containing a specific sequence of Asp-Glu-Val-Asp (DEVD) was cleaved, resulting in the release of CuO nanoparticles from the above magnetic probe. Subsequently, the CuO nanoparticles were acidolyzed to generate Cu2+, which induced the ultrafast formation of SA gel on the HFQCM Au chip and SA/MWCNTs-hemin composite gel on the SnS2/ITO electrode within 30 s. Such rapid gelation produced a large frequency response in the HFQCM mode due to the drastic viscoelastic change on the QCM sensing surface and resulted in an obvious photocurrent polarity switching in the PEC mode. Thus, caspase-3 activity was assayed ultrarapidly and ultrasensitively: the entire assay process only required 16 min with a linear response range of 1 fg mL-1 to 100 ng mL-1 (detection limit of 0.32 fg mL-1) in HFQCM mode and 10 fg mL-1 to 100 ng mL-1 (detection limit of 2.75 fg mL-1) in PEC mode. This platform is anticipated to serve as a robust tool in bioanalysis through changing the specific biorecognition elements and has great potential in disease early diagnosis and drug discovery.

Developing hydrogen (H2) sensors with ultralow detection limits, high response, and room-temperature operation is critical for the safe utilization of H2 energy. Herein, we report a highly sensitive H2 sensor based on palladium nanoparticle (Pd NP)-decorated silicon microcone (Si MC) arrays, with a systematic investigation of metal deposition conditions. Large-area, uniform, and smooth Si MC arrays were fabricated via metal-assisted chemical etching (MACE). The Pd deposition angle (0-90°) plays a vital role in sensing performance. The optimized 3 Pd-75° sensor (3 nm Pd, 75° deposition) exhibits an exceptional response of 2148.9% toward 10,000 ppm H2 at room temperature, along with fast recovery (∼4 s), good humidity tolerance, long-term stability, and excellent selectivity. Notably, it achieves an ultrawide quantitative detection range from 10 ppb to 2000 ppm. Furthermore, Pt modification reveals a trade-off between catalytic activity and electrical response: while Pt accelerates H2 dissociation and diffusion, it reduces response magnitude due to active site blocking and enhanced conduction pathways. The superior sensing performance arises from the synergistic effects of Pd catalysis, Pd/Si interfacial charge modulation, and the high surface area of the Si MC architecture. This work provides a promising strategy for low-power, high-performance room-temperature H2 sensing.

This study successfully synthesized a new zinc-based metal-organic framework material {[Zn(qdda)(bpy)0.5]·3H2O} (Zn-MOF) by the solvothermal method and systematically investigated its performance as a fluorescent material for the simultaneous sensing of the antibacterial drug Cinoxacin (CNX) and Vitamin B2 (VB2). The structure, morphology, and composition of the material were comprehensively characterized by single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR). Fluorescence experiments demonstrated that the Zn-MOF demonstrates significant selectivity and sensitivity toward both CNX and VB2, with detection limits of 9.2 nM and 24 nM, separately, a rapid response (within 60 s), as well as excellent anti-interference ability and recyclability. The observed fluorescence quenching was attributed to a synergistic mechanism involving competitive absorption (CA), resonance energy transfer (RET), and photoinduced electron transfer (PET). In a simulated saliva and urine environment, the material showed satisfactory spike recovery rates for CNX and VB2, confirming its reliability in practical sample detection. This work opens a new avenue for developing high-performance MOF-based fluorescent sensors. Such sensors show great potential for the simultaneous detection of two analytes within complex biological environments.

The precise detection and profiling of biotoxins are of paramount importance in analytical and forensic toxicology. Investigating these toxicants within highly chaotic background matrices-ranging from postmortem biological fluids to suspected poisoning vehicles such as complex dietary and environmental samples-requires robust recognition molecules capable of overcoming severe interference. This comprehensive review summarizes recent analytical developments in biotoxin detection, categorizing molecular recognition platforms into three primary types: immunological recognition (antibodies and recombinant derivatives), aptamer-based recognition, and entirely synthetic recognition (molecularly imprinted polymer, MIP). To meet the rigorous ultra-trace demands of medicolegal analysis, we further discuss the strategic integration of these recognition elements with powerful catalytic amplification cascades, highlighting the transition from natural biological enzymes to highly durable nanozymes and DNAzymes. By detailing recent structural optimizations and preparation strategies, this review critically evaluates the respective advantages, matrix tolerances, and limitations of each recognition mode when applied to diverse and challenging analytical samples. Finally, we provide a forward-looking perspective on the translational potential of these specific binding agents, emphasizing how computational rational design and portable integration will overcome practical bottlenecks in modern toxicological investigations.

Propyl gallate (PG), a widely used synthetic phenolic antioxidant, has raised health concerns due to its potential risks from overexposure. Traditional methods such as chromatography are typically time-consuming, labor-intensive, and not suitable for on-site rapid screening. In this work, we successfully fabricated ultra-small Cu2-xSe nanoparticles using plant-derived ginkgo biloba polysaccharide (GBLP) as a protective agent and ascorbic acid (AA) as a reducing agent. The generated Cu2-xSe nanoparticles exhibited excellent peroxidase-like activity to catalyze the chromogenic reaction of H2O2 and 3,3',5,5'-tetramethylbenzidine (TMB). The presence of PG could inhibit this reaction owing to its antioxidant properties, enabling quantitative detection of PG with a detection limit (LOD) of 2.25 µM. By incorporating a smartphone and ImageJ software, a portable colorimetric device was developed for visual intelligence detection, achieving a LOD of 6.87 µM. Experimental data of real samples demonstrated that the recoveries of PG ranged from 101.52% to 106.60%, confirming the accuracy and practicality of the method. This work offered a novel nanozyme-based strategy for rapid and intelligent monitoring of PG in food products and provides a reliable, low-cost technical option for PG detection in edible oils, with prospects in the rapid screening of actual food samples.

Cu[2+] and H2S participate in vital physiological activities, especially mitochondrial function. Endogenous H2S has served as a critical biomarker of liver injury. Accordingly, detecting Cu[2+] and H2S in mitochondria, as well as monitoring H2S fluctuations in living cells and intact organisms (especially in the liver), is of great significance for elucidating their mitochondrial physiological roles and evaluating the progression of liver-related disorders.

Oxidative desulfurization (ODS) is an effective technology for achieving ultra-low sulfur levels in fuels to meet stringent environmental regulations. This study evaluates the effectiveness of an Fe@KL/S-g-C3N4 (Fe-doped Kraft lignin coupled with S-g-C3N4) nanocomposite for the oxidative desulfurization of dibenzothiophene (DBT) from model fuel. The synthesis and electronic structure of the composite were confirmed using FTIR, Raman spectroscopy, PL, UV-visible spectroscopy, XRD, FE-SEM, EDX, and XPS analyses, which confirmed that Fe-modified lignin was successfully coordinated with the S-g-C3N4 framework. The incorporation of iron and lignin improved Fe[3+] redox cycling and •OH generation, increased active site accessibility, and lowered the optical band gap to 1.85 eV, which enhanced Fenton-like radical generation. The Box-Behnken Design (BBD) optimization identified the optimum reaction conditions as 0.3 g of catalyst, 32.5 min reaction time, and 60 °C. With H2O2 used as a green oxidant, a maximum sulfur removal of 98.37% was achieved. This study demonstrates that Fe@KL/S-g-C3N4 is a high-performance, economical and sustainable heterogeneous catalyst for ultra-low sulfur fuel production, while exhibiting high structural stability and reusability over multiple cycles.

Chlorogenic acid (CGA), a core antioxidant in functional foods, requires accurate and rapid monitoring to ensure food quality, safety and production standardization, which is the practical and theoretical basis for developing its dedicated sensor. Unlike traditional HPLC (complex preprocessing, high cost, time-consuming), this study synthesized a NiFe2O4/A-CN composite by pyrolyzing a two-dimensional zeolite imidazole framework to obtain accordion-like N-doped carbon (A-CN), followed by ultrasonic loading of hydrothermally prepared NiFe2O4 nanoparticles. The composite combines A-CN's conductive framework with NiFe2O4's electroactive sites, creating a synergistic interface that efficiently adsorbs and detects CGA. The resulting electrochemical sensor shows a wide linear range (5 × 10[-10]-2 × 10[-6] M), ultra-low detection limit (1.0 × 10[-11] M), excellent recovery (98.9-102.2%) in actual food samples (yellow peaches, lemons, Tangerines), validated by UV-Vis, offering a faster, more cost-effective alternative for rapid and precise CGA detection in foods.