In this study, a donor–acceptor (D–A) conjugated zinc/copper-phthalocyanine covalent-organic polymer [CuPc-PDA-COP(Zn)] with homogeneously dispersed dual-atomic sites was constructed for chronic wound healing by coupling a multimodal antibacterial mechanism and efficient reactive oxygen species (ROS) scavenging. The electronic structure of CuN bond in CuPc-PDA-COP(Zn) can be regulated by the incorporation of ZnN site, resulting in an upshifted d-band center toward the Fermi level. Due to the intrinsic photothermal properties of Pc molecules, D–A conjugated structure, and the presence of abundant dual-atomic sites, CuPc-PDA-COP(Zn) exhibits enhanced photocarrier generation, facilitated electron delocalization, and excellent mimetic enzyme activity. Consequently, it demonstrates excellent photothermal conversion efficiency, high ROS production, controlled metal ion release, and superior antioxidant performance. As a result, CuPc-PDA-COP(Zn) shows 100% antibacterial efficiency against Escherichia coli and Staphylococcus aureus, along with satisfactory outcomes for chronic wound healing. Moreover, CuPc-PDA-COP(Zn) serves as a ROS scavenger during the inflammatory and early proliferative phases, alleviating excessive ROS damage to endothelial cells, promoting neovascularization, and facilitating diabetic wound closure. This study not only broadens the biomedical applications of COPs but also provides valuable insight into the synergistic effect of multimodal antibacterial mechanisms and ROS scavenging in chronic wound healing.

The precise patterning of highly ordered organic semiconductor (OSC) thin-film arrays is paramount for advancing next-generation electronic devices. Herein, we report a ladder-like polysilsesquioxane (LPSQ) strategy to synthesize two functional analogs with tunable surface energies and robust dielectric properties. These LPSQ dielectrics, functionalized with alkyl or fluoroalkyl side chains, serve a dual role as both gate insulators and patterning layers to guide the blade-coating of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT). This approach yields highly aligned arrays suitable for three-dimensional integration in flexible electronics. The synergistic combination of dense LPSQ dielectric packing and aligned semiconductor domains leads to excellent organic thin-film transistor (OTFT) performance, achieving an approximately four-fold improvement in field-effect mobility compared to conventional standard silicon oxide dielectrics. Moreover, the patterned LPSQ dielectrics enable high-resolution C8-BTBT patterning on plastic substrates, supporting the 4-inch-scale 3D integration of flexible logic circuits, including inverters (voltage gain >100), NOR gates, and NAND gates.

Porous-organic frameworks (POFs) — metal–organic frameworks (MOFs), covalent-organic frameworks (COFs), and hydrogen-bonded frameworks (HOFs) — are increasingly used in organic transistor (OT) sensors, including organic electrochemical transistors (OECTs), organic photoelectrochemical transistors (OPECTs), and organic field-effect transistors (OFETs). Their tunable pore apertures, ultra-high specific surface areas (up to ∼7000 m2 g−1), and customizable active sites allow POFs to serve as gate modulators, channel modifiers, catalytic amplifiers, and anti-fouling barriers whose effects are multiplied by the transistor’s intrinsic gain. This review examines the emerging structure–performance relationships between POF structural parameters (pore aperture, Brunauer–Emmett–Teller (BET) surface area, framework conductivity, node chemistry, heterojunction band alignment, and film morphology) and the figures of merit of OECTs, OPECTs, and OFETs — transconductance (gm), threshold voltage (Vth), and photocurrent gain. It covers the synthesis and integration strategies that place POFs in OT architectures and benchmarks the analytical performance of 22 analytes against established clinical and environmental reference methods. We conclude by identifying three critical bottlenecks — material stability, interfacial coupling, and scalable manufacturing — and propose a roadmap toward wafer-scale fabrication, interface-engineered heterojunctions, and data-driven POF design.

Electrocatalytic urea oxidation reaction (UOR) not only provides innovative solutions for clean energy development and environmental pollution control, but also promotes sustainable development through efficient resource recycling. Its technological breakthroughs hold significant implications for achieving carbon neutrality goals and establishing a green energy system. Benefiting from their high specific surface area, tunable pore structures, and modifiable electronic properties, diverse metal-organic frameworks (MOFs)-based UOR electrocatalysts have been exploited, such as pristine Ni-, Fe-, and Cu-based monometallic, bimetallic, or multiple metallic MOFs, MOFs-based composites, and MOFs-related derivatives. The porous framework exposes abundant active sites and enhances mass transfer, while the synergy between metal nodes and organic ligands optimizes electronic configurations to reduce reaction energy barriers. By integrating conductive substrates or constructing heterostructures, catalytic activity and stability are significantly enhanced. Varieties of strategies have been performed to further decrease the overpotential and accelerate the kinetics towards the UOR, such as modulating charge density and d-band center positions of active sites through metal-ligand coordination, inducing charge redistribution and enhancing electron transport via heterostructure interfaces, breaking electronic symmetry and boosting surface reactivity through defect engineering, adjusting atomic spacing and electronic band structures via strain engineering, reinforcing charge transfer and stabilizing active sites using conductive substrates, and enabling precise design through dynamic in-situ reconstruction and theory-guided optimization. This review explores the latest significant advances in the design and synthesis of MOFs-based UOR catalysts. Beyond highlighting recent breakthroughs in UOR catalysts, this review critically emphasizes the design strategies for urea electrolysis in the field of energy conversion and systematically addresses current challenges. Furthermore, this comprehensive research approach proposes forward-looking strategies for future research directions in energy conversion and carbon neutrality to advance the development of this emerging field.

The electrocatalytic nitrogen oxidation reaction (eNOR) offers a sustainable route for nitrate (NO3 -) synthesis, yet its practical application is limited by sluggish intermediate formation kinetics. Although center dot OH generated during water oxidation can promote the formation of the key *NOH intermediate, the cooperative mechanism between center dot OH and catalytic sites remains insufficiently understood. Herein, a spin-state modulation strategy is proposed to enhance *NOH generation under simulated solar irradiation, thereby markedly improving the NO3 - yield and Faradaic efficiency (FE) of the eNOR. A heterojunction catalyst consisting of CoMo-based layered double hydroxide nanosheets grown in situ on Ti3C2Tx MXene (CoMo-LDH@Ti3C2Tx) was developed to enable light-assisted eNOR. The incorporation of Mo into Co-LDH, together with the built-in electric field of the heterojunction, enhances Mo-Co orbital hybridization and induces a spin-state transition of Co3+ centers from t2g 6eg 0 to t2g 4eg 2 configuration. This electronic regulation strengthens N2 activation and accelerates *NOH formation via the cooperative involvement of two center dot OH radicals under illumination, thereby significantly boosting eNOR kinetics. Consequently, CoMo-LDH@Ti3C2Tx delivers NO3 - yield of 198.55 mu g h-1 mgcat. -1 and FE of 46.22% under solar light, outperforming dark conditions and state-of-the-art catalysts. These findings underscore the critical roles of spin-state engineering and radical synergy in advancing sustainable nitrate production.

Trace-level pesticide residue detection in food and environmental matrices is greatly challenged by complex compositions and interfering substances. Herein, a “signal-inversion” photoelectrochemical (PEC) aptasensor was constructed for chlorpyrifos (CPF) detection via electrode polarity inversion and competitive recognition. A bimetallic (CuCo) Salen-based covalent organic framework (CuCo-TAPB-COF) with excellent PEC performance was employed as the bioplatform for single-stranded DNA (ssDNA) immobilization. Hybridization between the aptamer/Cu@Cu₂O complex with COF-immobilized ssDNA induced a distinct PEC signal inversion. The CPF-triggered cathodic-to-anodic signal shift exhibited a positive correlation with CPF concentration, enabling effective signal amplification. The sensor achieved a low detection limit of 0.176 pg mL−1 within a linear range from 1 pg mL−1 to 1.0 μg mL−1, and outperformed most CPF reported biosensors with high selectivity, reproducibility, stability and practical applicability. This work provides a versatile strategy for designing high-performance COF-based PEC aptasensors and promotes advanced PEC sensing for environmental and food safety monitoring.

An ultrasensitive electrochemiluminescence (ECL) biosensor was established by combining CRISPR/Cas12a technique and semiconductive bimetallic-organic framework (scMOF) [[CuxNi3−x(HITP)2] (HITP = 2,3,6,7,10,11-hexaiminotriphenylene)]] emitter and employed to detect Salmonella using the allosteric probe as the recognition component. Given that CuxNi3−x(HITP)2 has demonstrated large specific surface area, both in-plane and out-of-plane charge transfer ability, narrowed band gap, and enhanced separation of holes and electrons, it can be simultaneously employed as the superior ECL emitter and bioplatform for anchoring single-strand DNA (ssDNA), thus improving the detection sensitivity toward Salmonella. The CRISPR/Cas12a-based system can specifically recognize the target sequence of Salmonella and activate the nuclease activity of Cas12a, and the activated Cas12a possesses trans-cleavage ability toward ssDNA. The CuxNi3−x(HITP)2 emitter is then released, resulting in the decline of the ECL response. The developed CuxNi3−x(HITP)2-CRISPR/Cas12a-based ECL biosensor exhibits the ultralow detection limit of 0.25 CFU mL− 1 in the linear range from 1.0 CFU mL− 1 to 106 CFU mL− 1, significantly lower than those of reported ones. Furthermore, the developed biosensor exhibits outstanding overall biosensing properties with high selectivity, favorable reproducibility and stability, together with promising practical applicability for the determination of Salmonella in a variety of foodstuffs.

The electrocatalytic ammonia oxidation reaction (eAOR) holds great potential for sustainable hydrogen production but is limited by sluggish kinetics. In this study, a novel 2D/2D heterojunction, Cu-MoS2/Cu3(HIB)2 (HIB: 1,2,3,4,5,6-hexachlorobenzene), is fabricated via in situ growth of a conductive copper-based metal-organic framework (Cu3(HIB)2) around Cu-doped MoS2. This heterojunction integrates abundant sulfur vacancies, modulates electron density at active sites, and facilitates rapid electron transfer. As a result, it exhibits significantly enhanced eAOR and hydrogen evolution reaction (HER) performance compared to individual components. The assembled electrolyzer achieves approximate to 100% ammonia removal and a high hydrogen production rate of 15.3 mL h-1 at 1.60 V versus RHE. In situ Fourier transform infrared (FT-IR) spectroscopy and density functional theory analyses reveal that S vacancies and Cu doping induce electron localization and orbital hybridization (Cu 3d, Mo 4d, S 2p), stabilizing Mo active sites and promoting ammonia (NH3) adsorption and activation. The formation and transformation of intermediates are optimized, facilitating the selective conversion of NH3 to nitrogen (N2). This study provides valuable insights into the design of bifunctional electrocatalysts via dimensional heterojunctions and demonstrates a promising strategy for coupling wastewater treatment with hydrogen production.

Metal-organic frameworks (MOFs) have garnered significant interest as promising anode materials for lithium-ion batteries (LIBs). Nonetheless, their application is hindered by limited rate capability and insufficient cycle performance. Herein, core/sheath structured Ni-MOF@multiwalled carbon nanotube (MWCNT) composites were hydrothermally synthesized by employing 2, 3, 6, 7, 10, 11-hexahydroxytriphenyl (HHTP) as ligands and Ni2+ as central metal ion nodes. MWCNTs can serve as efficient highways for rapid electron transport in this unique structure. The Ni-MOF nanorods, grown on the sidewalls of the MWCNT matrix, offer abundant accessible active sites for Li+ storage. As anticipated, the optimized Ni-MOF@MWCNT-30 achieved a lithium storage capacity of 518 mAh g-1 after 200 charge/discharge cycles at 0.2 A g-1, representing a remarkable 318 % increase over the bare Ni-MOF (124 mAh g-1). Furthermore, after 1000 charge/discharge cycles at 0.5 A g-1, it maintained a discharge capacity of 446 mAh g-1 with a coulombic efficiency of 99.2 %. These findings provide insights for designing MOF-based anode materials for next-generation LIBs, emphasizing large capacity and excellent cycling performance.

We have developed a novel electrochemical-colorimetric dual-modal sensor based on a metallosalen-based covalent organic framework (Salen-COF) for separate electrochemical quantification of uric acid (UA) and dopamine (DA) and colorimetric screening of their total amount. The Salen-COF was synthesized via a Schiff-base condensation between a bimetallic CuCu-Salen complex and melamine (CuCu-MA-COF), yielding a highly ordered porous architecture featuring atomically dispersed CuCu-N2O2 sites, an extended π-conjugated backbone, and electron-deficient triazine units. This unique combination endows the material with rapid electron transfer kinetics, efficient electrocatalytic capability, and peroxidase (POD)-mimicking enzymatic activity. Leveraging these properties, the resulting electrochemical sensor delivered exceptional performance, giving low limits of detection (LODs) of 0.885 and 1.699 μM within linear ranges from 5 to 50 μM and 80-500 μM for DA, and LODs of 0.991 and 1.637 μM within linear ranges from 5 to 80 μM and 100-500 μM for UA. When simultaneously detecting DA and UA, the electrochemical sensor had the low LODs of 1.375 μM and 1.065 μM within the wide range of 5-500 μM, respectively. Furthermore, the CuCu-MA-COF-based colorimetric sensor showed the low LODs of 10.65 nM and 0.374 μM within the range from 0 to 200 μM for DA and UA, respectively. Critically, this dual-modal sensor demonstrates high selectivity against common interferents, excellent operational stability, outstanding reproducibility, and reliable performance in real-sample analysis, underscoring its strong potential for practical, non-invasive health monitoring in point-of-care settings.

The precise detection of microRNAs (miRNAs) in tumor tissue is vital for the early diagnosis of cancer. In this work, we propose an electrochemiluminescence (ECL) aptasensing strategy for the sensitive detection of miRNA-122 in living cancer cells. To tremendously amplify the ECL response, a zinc-porphyrin-organic framework embraced with ZnO nanoparticles (NPs), which was synthesized through solvothermal synthesis using 5,10,15,20-tetra(4-pyridyl)porphyrin (TPyP) as linking ligand and zinc nitrate as precursor (represented by Zn-TPyP@ZnO), simultaneously served as bioplatform and ECL emitter in the presence of the coreactant K2S2O8. The generation of a microinterface between Zn-TPyP and ZnO NPs endowed fast electron transfer, improved catalytic performance, and superior biocompatibility. These advantages of the Zn-TPyP@ZnO heterojunction confers the system with strong reduction capability toward S2O82− to generate SO4•− and toward O2 to produce O2•− or •OH, as well as excellent anchoring capability for the miRNA-122-targeted aptamer. Therefore, the developed Zn-TPyP@ZnO-based ECL aptasensor demonstrated a wide linear detection range from 10 fM to 10 nM with an ultralow detection limit of 0.77 fM, accompanied with high selectivity, good stability, and excellent reproducibility. The constructed ECL aptasensor also showed promising application for the detection of miRNA-122 in living cancer cells. Thereby, the present work not only provides a new ECL aptasensing strategy for the sensitive detection of miRNA in living cancer cells but also puts forward the advancement of the early diagnosis of tumors.

Covalent-organic frameworks (COFs) have demonstrated the features of periodic crystalline structures, tailorable chemical functionalities, robust stability, intrinsic catalytic activity, and modifiable biocompatibility. These structural and functional merits endow COFs with exceptional nanozyme activities and superior performance as enzymes carriers. When integrated with advanced sensing technologies, COF-based nanozymes have shown remarkable potential in food safety analysis, enabling sensitive and selective detection of a wide range of contaminants of organic pollutes, small biomolecules, mycotoxins, hazard ions, amino acids, food additives, and foodborne bacteria, viruses, and food allergens. This review comprehensively summarizes the structure-activity relationships of COF-based nanozymes, highlights recent advancements in their rational design, functional modification, and catalytic mechanism exploration, and systematically discusses their practical applications in food safety testing, providing critical insights for the development of high-performance COF-based sensing platforms. Future research focused on functional customization and standardized frameworks could unlock broader practical applications.

This work developed a novel "on-off-on" electrochemiluminescence (ECL) aptasensor for sensitive, selective monitoring of ochratoxin A (OTA) in food, combining a competitive aptasensing strategy with dual-modal quenching. A donor-acceptor (D-A) conjugated covalent triazine framework (CTF, synthesized via Schiff-based solvothermal method using 4,4 ',4 ''-(1,3,5-triazine-2,4,6-triyl)tris[benzaldehyde] and 2,2 '-bipyridine-5,5 ' diamine, denoted TFPT-BPY-CTF) was used both as a high-performance ECL emitter (with K2S2O8) and a bioplatform to anchor single-strand DNA (ssDNA) complementary to the OTA aptamer. To enhance electron transfer efficiency, the aptamer probe was modified by MnxFeyOz contained with the mixed phases of MnFe2O4, alpha-MnO2, and Fe2O3, generating the Apt/MnxFeyOz complex. Subsequently, the Apt/MnxFeyOz complex was successfully deposited onto the ssDNA/TFPT-BPY-CTF surface via the formation of the aptamer/ssDNA double strands. Thus, this configuration led to effective quenching of the strong ECL signal of the D-A TFPT-BPY-CTF through a dualmode mechanism involving both energy resonance transfer and electron transfer. Upon introduction of OTA, however, the formed G-quadruplex structure between OTA and the aptamer induced the release of the Apt/ MnxFeyOz probe, thereby enabling the recovery of the ECL signal. Ultimately, the ultrasensitive detection of OTA using the signal "on-off-on" TFPT-BPY-CTF-based ECL aptasensor. The constructed ECL aptasensor not only exhibited a wide linear range from 1.0 pg mL- 1 to 100 ng mL- 1 with an ultralow detection limit of 0.21 pg mL- 1 but also demonstrated superior selectivity, high stability, and good reproducibility, alongside promising practicality. This novel ECL aptasensor based the CTF provides an efficient, reliable, and rapid approach for the analysis of mycotoxins in food products.

Chronic tetracycline (TET) exposure in water/food triggers drug resistance, immune damage and allergies, requiring rapid, sensitive TET detection to safeguard food and human safety. Herein, a novel photoelectric active multivariate copper-based metal-organic framework (Cu-MOF) constructed from tetra(4-carboxyphenyl)porphine (TCPP) and 5,10,15,20-tetra(4-pyridyl)porphyrin (TPyP) (denoted as Cu-TCPP/TPyP) was employed as the bioplatform for the fabrication of a photoelectrochemical (PEC) aptasensor for the efficient detection of TET. The Cu-TCPP/TPyP was synthesized via the coprecipitation method using TCPP and TPyP as dual ligands and copper ions as the metal precursor. Due to the dual-coordination metal nodes, the attained Cu-TCPP/TPyP possessed rich defects, large pore size, and high specific surface area relative to Cu-MOFs prepared using the sole ligand. The Cu-TCPP/TPyP also showed enhanced photoelectric conversion efficiency due to the suppressed combination of electron-hole pair, enhanced visible light utilization, and high carrier density. The manufactured Cu-TCPP/TPyP-based PEC aptasensor thus exhibited the ultralow limit of detection of 0.76 fg mL–1 toward TET within the concentration from 1 fg mL–1 to 10 ng mL–1, markedly lower than most reported TET biosensors. In view of the high selectivity, good reproducibility, and high long-term stability, the constructed aptasensor possesses wide practicability for the sensitive determination of TET in diverse samples, which was also confirmed by the standard conventional determination method. The presented PEC aptasensor puts forward the advancement of the MOF-based biosensor in the field of the analysis of food safety.

In this work, a complementary dual-modal immunosensing strategy was fabricated for the sensitive and selective detection of zearalenone (ZEN) by integrating immunochromatographic and electrochemical biosensing methods. For this, bimetallic NiFe Prussian blue analogue (NiFe-PBA) was simultaneously employed as a matrix for labelling ZEN-targeted antibody and the sensitive layer for anchoring antibody to construct an efficient immunochromatographic immunosensor (ICI) and electrochemical immunosensor (ECI), respectively. Due to porous network, good functionality, high bioaffinity, and rich metal redox, NiFe-PBA-based complementary dual-modal immunosensor exhibited low limit of detection, high selectivity and stability, and accepted practicality. Particularly, the developed ECI illustrated fast response, portability, and potentially commercial application. Coupling the ICI and ECI sensing strategy can markedly enhance the accuracy and sensitive detection of ZEN in complicated environments. This dual-modal ICI-ECI immunosensing strategy exhibits significant potential for the precise detection of mycotoxin in various agricultural products and improve the quality control for foods.

A novel amplified photoelectrochemical (PEC) aptasensor was developed based on the photoelectronic active and donor-acceptor (D-A) conjugated covalent organic framework (COF) for the efficient detection of zearalenone (ZEN). The D-A-conjugated COF synthesized through the reaction between trinuclear copper cluster (Cu3L3) and 4,4 ',4 ''-(1,3,5-triazine-2,4,6-triyl)trianiline (TAPT) (denoted as Cu3L3-TAPT-COF) comprised rich Cu-N2 singleatom sites and exhibited high photoactivity, narrow bandgap, and n-type semiconductor feature. It was simultaneously employed as PEC electrode and bioplatform for anchoring single-stranded DNA. Moreover, the p-type ZnIn2S4 semiconductor anchors hairpin probe strands that hybridized with the ZEN-target aptamer. By combining the target-modulated competitive binding method and the multivariate signal-amplified strategy, the Cu3L3-TAPT-COF-based PEC aptasensor exhibited a wide linear range from 0.1 pg mL- 1 to 20 ng mL- 1 and a low detection limit of 24 fg mL- 1, along with excellent and widespread practical applicability, offering promising applications in food safety.

A new photopolymerizable organic-inorganic (O-I) hybrid sol-gel material, AUP@SiOx-184, has been synthesized and utilized as a gate dielectric in flexible organic thin-film transistors (OTFTs). The previously reported three-arm alkoxy-functionalized silane amphiphilic polymer has yielded stable O-I hybrid materials comprising uniformly dispersed nanoparticles in the sol state. In this study, a photosensitizer was introduced, facilitating curing effects under ultraviolet light. Photo-crosslinking enhances the stability of hydroxyl radicals within inorganic nanoparticles, thereby minimizing device hysteresis. This approach also contributes to achieving a low leakage current and a high dielectric constant (high-k) while maintaining reduced thickness. Moreover, AUP@SiOx-184 films are amenable to patterning through UV photopolymerization and can be successfully produced using printing techniques. Compared to other materials, they exhibit outstanding flexibility and improved insulating capabilities. Additionally, OTFTs incorporating AUP@SiOx-184 layers demonstrate extremely stable driving features on flexible substrates. Selective printing and specific patterning play crucial roles in the fabrication of logic circuits. This synthesis strategy has resulted in integrated logic devices that have successfully demonstrated their functionality, highlighting its value for producing functional O-I hybrid materials. Utilizing AUP@SiOx-184 as a gate dielectric in OTFTs showcases its potential to advance electronic technologies that are both flexible and high-performing.

Food safety issues caused by diverse contaminants (antibiotics, pesticides, heavy metal ions, mycotoxins, organic pollutants, foodborne bacteria, etc.) have garnered increasing attention in safeguarding public health and ensure sustainable economic development. Developing advanced detection techniques is critically important to precisely and sensitively identify these pollutants present in foodstuffs or environments.‌ Covalent-organic frameworks (COFs), a newly emerged kind of porous-organic frameworks, have been widely utilized in food safety analysis because of their exceptional physical, chemical, and optoelectronic properties. This review systematically summarizes the latest progress and current situation about the advancement of COFs-based nanomaterials in the detection of food contaminants in complex environments and food matrices. Based on the discussion of structural features and categories of COFs-based nanomaterials, this study elucidates the relationship between the structural design of COFs and their sensing performance. Moreover, the adsorption and biosensing mechanism of the detection of food pollutants using COFs-related sensors are analyzed, together with the summarization of the diversified detection techniques. This work uniquely bridges the structural chemistry of COFs with their pollutant-specific sensing performance by establishing a systematic correlation between monomer-level design and contaminant recognition mechanisms. Furthermore, this review summarizes the current research progress on the detection of various food pollutants using COF-based sensors. Finally, the review highlights existing challenges and outlines future directions, offering researchers a clear pathway from molecular design to practical application. This review is expected to facilitate the development of next-generation, precision-targeted COF-based sensors for enhanced food safety monitoring.

A designed "on-off-on" signal-switchable electrochemiluminescence (ECL) aptasensor based on a donor-acceptor (D-A) conjugated covalent triazine framework (CTF) has been constructed for the sensitive and accurate detection of aflatoxin B1 (AFB1) with the assistance of a nicking endonuclease (Nb.BbvCI)-powered DNA walking machine. The D-A conjugated CTF, generated from the reaction between 2,4,6-tris(4-formylphenyl)-1,3,5-triazine (TFPT) and tris(4-aminophenyl)methane (TAPM) (denoted as TFPT-TAPM-CTF), simultaneously serves as a superior ECL emitter and a platform for anchoring the bioprobe. The high ECL response of TFPT-TAPM-CTF can be quenched by the anchored Cy5-labeled single-strand DNA (Cy5-ssDNA) via ECL resonance energy transfer. Furthermore, the immobilization of the double-strand DNA generated between the AFB1-targeting aptamer and the DNA walker (Hp) reduces the ECL response of TFPT-TAPM-CTF. When detecting AFB1, the aptamer separates from the double-strand DNA to capture specific targets, resulting in the hybridization of the free Hp strand and Cy5-ssDNA. With the assistance of Nb.BbvCI, the released partial Cy5-ssDNA helps recover the ECL response of TFPT-TAPM-CTF to some extent, further liberating the Hp strand to autonomously bind to another Cy5-ssDNA and trigger a new cleavage process. In addition to its high selectivity and promising practicality, the constructed ECL aptasensor shows an ultralow detection limit of 0.59 pg·mL-1 within a wide range from 1.0 pg·mL-1 to 5.0 × 104 pg·mL-1. This work broadens the application of CTF in the food safety field and provides a new aptasensing strategy for the sensitive and precise inspection of mycotoxins in food products.

An efficient and facile nitrite (NO2-) detection system was developed using Fe3O4@Au-Cu/MOF, which was manufactured through self-assembly as the nanozyme, and a PEDOT:PSS/RGO thin film produced by chemical synthesis as the counter electrode, in conjunction with smartphone-based colorimetry. The Fe3O4@Au-Cu/MOF nanozyme exhibits remarkable catalytic efficiency and can significantly enhance the conversion of NO2-. PEDOT:PSS/RGO films exhibit outstanding electron transport and electrochromic properties. The color of PEDOT:PSS/RGO films can be modified by applying voltage and the electronic current generated by NO2- within the reaction system. The colorimetric assessment of film color alteration using a smartphone, supplemented by electrochemical validation. Under ideal conditions, the sensor detected NO2- within a linear range of 0.01 to 100 mmol/L and exhibited a detection limit of 3.37 μmol/L. This method demonstrated no significant difference compared to the results obtained using the electrochemical method and was effectively employed for the detection of NO2- in real samples.