Biomimetic Synthesis of Ultrafine Mixed-Valence Metal-Organic Framework Nanowires and Their Application in Electrochemiluminescence Sensing

Recent and emerging trends of metal-organic frameworks (MOFs)-based sensors for detecting food contaminants: A critical and comprehensive review

Interest in the use of sensors based on metal-organic frameworks (MOFs) to detect food pollutants has been growing recently due to the desirable characteristics of MOFs, including uniform structures, large surface area, ultrahigh porosity and easy-to-functionalize surface. Fundamentally, this review offers an excellent solution using MOFs-based sensors (e.g., fluorescent, electrochemical, electrochemiluminescence, surface-enhanced Raman spectroscopy, and colorimetric sensors) to detect food contaminants such as pesticide residues, mycotoxins, antibiotics, food additives, and other hazardous candidates. More importantly, their application scenarios and advantages in food detection are also introduced in more detail. Therefore, this systematic review analyzes detection limits, linear ranges, the role of functionalities, and immobilized nanoparticles utilized in preparing MOFs-based sensors. Additionally, the main limitations of each sensing type, along with the enhancement mechanisms of MOFs in addressing efficient sensing are discussed. Finally, the limitations and potential trends of MOFs-based materials in food contaminant detection are also highlighted.

Applications of cerium-based materials in food monitoring

With the rapid development of society, food safety to public health has been a topic that cannot be ignored. In recent years, lanthanide-based materials are studied to be potential candidates in the detection of food samples. Cerium (Ce)-based materials (such as Ce ions, CeO2, Ce-metal organic framework (Ce-MOF), etc.) have also attracted more attention in food detection by virtue of colorimetric, fluorescence, sensing, and other methods. This is because the mixed valence of Ce (Ce3+ and Ce4+), the formation of oxygen vacancies, and their optical and electrochemical properties. In this review, Ce-based materials will be introduced and discussed in the field of food detection, including biogenesis, construction, catalytic mechanisms, combination, and applications. In addition, the current challenges and future development trend of these Ce-based materials in food safety detection are also proposed and discussed. Therefore, it is meaningful to explore the Ce-based materials for detection of biomarkers in food samples.

Gold-copper-doped lanthanide luminescent metal-organic backbone induced self-enhanced molecularly imprinted ECL sensors for ultra-sensitive detection of chlorpyrifos

Herein, a self-enhanced molecularly imprinted polymer luminescence (MIP-ECL) sensing platform based on gold-copper doped Tb-MOFs (Au@Cu:Tb-MOFs) was constructed for ultra-sensitive detection of chlorpyrifos (CPF). In this work, Au@Cu:Tb-MOFs as co-reaction promoters greatly improve the ECL emission signal, while Au@Cu:Tb-MOFs were used as cathode emitters. And chlorpyrifos and 4,7-bis(thiophene-2-yl)benzo [c][1,2,5] thiadiazole were electropolymerized on electrode surface to form MIP, where this films with thiophene derivatives could greatly improve ECL signal. Notably, the introduction of MIP as recognition elements enabled specific identification of target analytes, in which molecular docking technique validated target analyte and functional monomers are tightly bound through Pi-alkyl interaction. As the concentration of CPF increases, the ECL signal gradually decreases, showing a good linear relationship in the range of 0.1-106 pg/mL with a low detection limit (LOD) of 0.029 pg/mL. Moreover, actual sample testing experiment of this method displayed a special correlation in organophosphorus detection and development potential in actual sample analysis.

Triple signal-enhanced electrochemiluminescence strategy using iron-based metal-organic frameworks modified with Ru(II) complexes for carcino-embryonic antigen detection

The development of a highly efficient electrochemiluminescence (ECL) emitter represents an effective strategy for enhancing the sensitivity and repeatability of ECL immunosensors. In this study, a sandwich-type ECL immunosensor with triple enhancement was developed to detect carcino-embryonic antigen (CEA). This sensor is based on a porous structure of iron-based metal-organic framework (NH2-MIL-88(Fe)), encapsulating the luminescent tris(2,2'-bipyridine)ruthenium (II) (Ru (bpy)32+), Au@MoS2 with a 3D nanoflower structure as an enhanced substrate. In this system, the MOFs framework encapsulated luminophore was realized to solve its water solubility to reach stable luminescence, as well as the triple enhancement effect based on the principle of amino catalysis, Mo4+/Mo6+ active site conversion, and gold nanoparticles (Au NPs) promotion, which significantly enhanced the detection sensitivity. Furthermore, the ECL immunosensor demonstrated successful application in the highly sensitive and selective detection of CEA, achieving a detection limit of 38.9 fg mL-1. The sensor demonstrates remarkable sensitivity, specificity, stability, repeatability, and practicality in the analysis of human serum samples. This investigation presents a highly effective approach for the ultrasensitive detection of trace proteins.

Developments in food neonicotinoids detection: novel recognition strategies, advanced chemical sensing techniques, and recent applications

Neonicotinoid insecticides (NEOs) are a new class of neurotoxic pesticides primarily used for pest control on fruits and vegetables, cereals, and other crops after organophosphorus pesticides (OPPs), carbamate pesticides (CBPs), and pyrethroid pesticides. However, chronic abuse and illegal use have led to the contamination of food and water sources as well as damage to ecological and environmental systems. Long-term exposure to NEOs may pose potential risks to animals (especially bees) and even human health. Consequently, it is necessary to develop effective, robust, and rapid methods for NEOs detection. Specific recognition-based chemical sensing has been regarded as one of the most promising detection tools for NEOs due to their excellent selectivity, sensitivity, and robust interference resistance. In this review, we introduce the novel recognition strategies-enabled chemical sensing in food neonicotinoids detection in the past years (2017-2023). The properties and advantages of molecular imprinting recognition (MIR), host-guest recognition (HGR), electron-catalyzed recognition (ECR), immune recognition (IR), aptamer recognition (AR), and enzyme inhibition recognition (EIR) in the development of NEOs sensing platforms are discussed in detail. Recent applications of chemical sensing platforms in various food products, including fruits and vegetables, cereals, teas, honey, aquatic products, and others are highlighted. In addition, the future trends of applying chemical sensing with specific recognition strategies for NEOs analysis are discussed.

Room-Temperature Synthesized Iron/Cobalt Metal-Organic Framework Nanosheets with Highly Efficient Catalytic Activity toward Luminol Chemiluminescence Reaction

Two-dimensional (2D) iron/cobalt metal-organic framework nanosheets (Fe/Co-MOF NSs) were synthesized via the cooperative self-assembly reaction of Fe3+/Co2+ and terephthalic acid at room temperature. The as-prepared 2D Fe/Co-MOF NSs display superior performance in catalysis of the chemiluminescence (CL) reaction between luminol and H2O2. The CL spectrum, UV-vis absorption spectroscopy, radical scavenger experiments, and electron spin resonance (ESR) spectroscopy are utilized to research the possible CL mechanism of the luminol-H2O2-Fe/Co-MOF NSs system. All results indicate that Fe/Co-MOF NSs present outstanding peroxidase-like activity and could catalyze H2O2 to produce 1O2, O2·-, and ·OH, which could react rapidly with the luminol anion radical and result in strong CL. With the highly efficient CL of the luminol-H2O2-Fe/Co-MOF NSs system, a sensitive sensor for the detection of dopamine (DA) is developed based on the inhibitory effect of DA on the CL intensity. Good linearity over the range of 50-800 nM is achieved with a limit of detection of 20.88 nM (S/N = 3). This research demonstrates that 2D Fe/Co-MOF NSs is a highly effective catalyst for luminol CL reaction and has great application potential in the CL field.

A review on nickel-rich nickel-cobalt-manganese ternary cathode materials LiNi0.6Co0.2Mn0.2O2 for lithium-ion batteries: performance enhancement by modification

The new energy era has put forward higher requirements for lithium-ion batteries, and the cathode material plays a major role in the determination of electrochemical performance. Due to the advantages of low cost, environmental friendliness, and reversible capacity, high-nickel ternary materials are considered to be one of ideal candidates for power batteries now and in the future. At present, the main design idea of ternary materials is to fully consider the structural stability and safety performance of batteries while maintaining high energy density. Ternary materials currently face problems such as low lithium-ion diffusion rate and irreversible collapse of the structure, although the battery performance can be improved utilizing coating, ion doping, etc., the actual demand requires a more effective modification method based on the intrinsic properties of the material. Based on the summary of the current research status of the ternary material LiNi0.6Co0.2Mn0.2O2 (NCM622), a comparative study of the modification paths of the material was conducted from the level of molecular action mechanism. Finally, the major problems of ternary cathode materials and the future development direction are pointed out to stimulate more innovative insights and facilitate their practical applications.

Emerging Insights into the Use of Advanced Nanomaterials for the Electrochemiluminescence Biosensor of Pesticide Residues in Plant-Derived Foodstuff

Pesticides have an important role in rising the overall productivity and yield of agricultural foods by eliminating and controlling insects, pests, fungi, and various plant-related illnesses. However, the overuse of pesticides has caused pesticide pollution of water bodies and food products, along with disruption of environmental and ecological systems. In this regard, developing low-cost, simple, and rapid-detecting approaches for the accurate, rapid, efficient, and on-site screening of pesticide residues is an ongoing challenge. Electrochemiluminescence (ECL) possesses the benefits of great sensitivity, the capability to resolve several analytes using different emission wavelengths or redox potentials, and excellent control over the light radiation in time and space, making it a powerful strategy for sensing various pesticides. Cost-effective and simple ECL systems allow sensitive, selective, and accurate quantification of pesticides in agricultural fields. Particularly, the development and progress of nanomaterials, aptamer/antibody recognition, electric/photo-sensing, and their integration with electrochemiluminescence sensing technology has presented the hopeful potential in reporting the residual amounts of pesticides. Current trends in the application of nanoparticles are debated, with an emphasis on sensor substrates using aptamer, antibodies, enzymes, and molecularly imprinted polymers (MIPs). Different strategies are enclosed in labeled and label-free sensing along with luminescence determination approaches (signal-off, signal-on, and signal-switch modes). Finally, the recent challenges and upcoming prospects in this ground are also put forward.

Vesicles as a Multifunctional Microenvironment for Electrochemiluminescence Signal Amplification

Vesicles as a typical interface-rich microenvironment can promote the reaction rate and the intermediate stability, which are promising for introduction in electrochemiluminescence (ECL) signal amplification. In this work, a kind of multilamellar vesicle obtained from sodium bis(2-ethylhexyl) sulfosuccinate (AOT) was used to modify the electrode surface. The AOT vesicle-modified microenvironment could significantly enhance the ECL performances for the luminol/O2 system in a neutral medium. The mechanism study demonstrated that the nanoscale multilamellar vesicles could maintain the vesicle structure on the electrode surface, which substantially improved the electron transfer and reaction rate, luminescence efficiency of the excited-state 3-aminophthalate anion, and stability of the superoxide anion radical. Alternatively, such a multifunctional microenvironment was also able to enhance the ECL signals from the tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)32+)/tripropylamine (TPrA) system. Moreover, another dodecyl dimethyl(3-sulfopropyl) ammonium hydroxide inner salt (DSB)-based vesicle was constructed to further verify the versatility of the vesicle-modified microenvironment for ECL signal amplification. Our work not only provides a versatile microenvironment for improving the efficiency of various ECL systems but also offers new insights for the microenvironment construction using the ordered assemblies in ECL fields.

Metal-organic frameworks (MOFs) based luminescent and electrochemical sensors for food contaminant detection

With the increasing population, food toxicity has become a prevalent concern due to the growing contaminants of food products. Therefore, the need for new materials for toxicant detection and food quality monitoring will always be in demand. Metal-organic frameworks (MOFs) based on luminescence and electrochemical sensors with tunable porosity and active surface area are promising materials for food contaminants monitoring. This review summarizes and studies the most recent progress on MOF sensors for detecting food contaminants such as pesticides, antibiotics, toxins, biomolecules, and ionic species. First, with the introduction of MOFs, food contaminants and materials for toxicants detection are discussed. Then the insights into the MOFs as emerging materials for sensing applications with luminescent and electrochemical properties, signal changes, and sensing mechanisms are discussed. Next, recent advances in luminescent and electrochemical MOFs food sensors and their sensitivity, selectivity, and capacities for common food toxicants are summarized. Further, the challenges and outlooks are discussed for providing a new pathway for MOF food contaminant detection tools. Overall, a timely source of information on advanced MOF materials provides materials for next-generation food sensors.

Aggregation-Induced Electrochemiluminescence Based on a Zinc-Based Metal-Organic Framework and a Double Quencher Au@UiO-66-NH2 for the Sensitive Detection of Amyloid β 42 via Resonance Energy Transfer

A novel sandwich electrochemiluminescence (ECL) biosensor based on aggregation-induced electrochemiluminescence resonance energy transfer (AIECL-RET) was designed for the sensitive detection of amyloid β42 (Aβ42). The synthesized silver nanoparticle-functionalized zinc metal-organic framework (Ag@ZnPTC) and gold nanoparticle-functionalized zirconium organic framework (Au@UiO-66-NH₂) were used as the ECL donor and acceptor, respectively. AgNPs were generated in situ on the surface of ZnPTC, which further improved the ECL intensity and the loading of antibody 1 (Ab1). Under the optimized experimental conditions, the linear detection range of Aβ42 concentration was 10 fg/mL to 100 ng/mL, and the detection limit was 2.4 fg/mL (S/N = 3). The recoveries of Aβ42 were 99.5-104%. The method has good stability, repeatability, and specificity. Ag@ZnPTC/Au@UiO-66-NH₂ provides an assay for the sensitive detection of disease biomarkers.

Enhancement of the sensing performance and stability of a MOF based-molecularly imprinted polymer by utilizing dual-ligands and triethanolamine catalysis

In this work, a terbium MOF-based molecularly imprinted polymer (Tb-MOF@SiO₂@MIP) was prepared using two ligands as organic linkers and triethanolamine (TEA) as a catalyst to improve the sensing performance and stability of the fluorescence sensors. The obtained Tb-MOF@SiO₂@MIP was then characterized using a transmission electron microscope (TEM), energy dispersive spectroscopy (EDS) Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). The results revealed that Tb-MOF@SiO₂@MIP was successfully synthesized with a thin imprinted layer of 76 nm. The synthesized Tb-MOF@SiO₂@MIP maintained 96% of its original fluorescence intensity after 44 days in aqueous environments because of appropriate coordination models between the imidazole ligands as a nitrogen donor and Tb (Ⅲ). Furthermore, TGA analysis results indicated that an increase in the thermal stability of Tb-MOF@SiO₂@MIP was attributed to the thermal barrier from a MIP layer. The Tb-MOF@SiO₂@MIP sensor responded well to the addition of imidacloprid (IDP) in the range of 2.07-150 ng mL^-1 with a low detection limit of 0.67 ng mL^-1. In vegetable samples, the sensor can quickly detect IDP levels with the average recovery ranging from 85.10 to 99.85% and RSD values ranging from 0.59 to 5.82%. The UV-vis absorption spectrum and density functional theory analysis results revealed that the inner filter effect and dynamic quenching process both contributed to the sensing process of Tb-MOF@SiO₂@MIP.

Vein-Like Ni-BTC@Ni3S4 with Sulfur Vacancy and Ni3+ Fabricated In Situ Etching Vulcanization Strategy for an Electrochemical Sensor of Dopamine

In this study, a novel Ni-BTC@Ni₃S₄ composite was fabricated by solvothermal reaction using an in situ etching vulcanization strategy and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and Brunauer-Emmett-Teller (BET) analyses. The existence of a sulfur vacancy and Ni³⁺ in the as-prepared vein-like Ni-BTC@Ni₃S₄ greatly promoted the electrochemical sensing activity of the materials. Herein, a simple electrochemical sensor (Ni-BTC@Ni₃S₄/CPE) has been fabricated and used for the detection of dopamine (DA). The current signal of the Ni-BTC@Ni₃S₄/CPE-modified electrode was linear with the concentration of DA in the range of 0.05-750 μM (R² = 0.9995) with a sensitivity of 560.27 μA·mM^-1·cm^-2 and a detection limit of 0.016 μM. At the same time, the sensor has good stability and anti-interference ability. This study could provide a new idea and strategy for the structural regulation of composite electrode-modified materials and sensitive sensing detection of small biological molecules.

A Sensitive Electrochemiluminescence Urea Sensor for Dynamic Monitoring of Urea Transport in Living Cells

A multiple signal-amplified electrochemiluminescence (ECL) urea sensor was designed based on a self-enhanced probe and SiO₂ photonic crystals for dynamic tracking of urea transmembrane transport. The self-enhanced probe (AuNR@Ru-LA) prepared by loading polyethyleneimine (PEI), lactobionic acid (LA), and Ru(dcbpy)₃²⁺ on gold nanorods (AuNRs) generated an initial ECL signal, and then the intensity was multiple-amplified by the enhanced light-scattering effect of SiO₂ photonic crystals and the co-reaction with urea. The as-prepared sensor exhibited excellent performance for the detection of urea in the range of 1.0 × 10^-10 to 1.0 × 10^-4 M with a detection limit of 8.8 × 10^-11 M at (3σ)/S. The AuNR@Ru-LA probes were labeled on HepG2 cells to construct a cytosensor with a detection range of 1.0 × 10³ to 2.0 × 10⁶ cells mL^-1. In addition, the dynamic changes of the extracellular urea concentration were tracked by monitoring the ECL signal of the cytosensor to study urea transmembrane transport. The developed strategy realized the amplification of multiple ECL signals and the tracking of urea transmembrane transport, which provided a novel dynamic detection method for small biomolecules.

Simple high-temperature annealing affords commercial carbon cloth with enhanced electrochemical performance for highly sensitive detection of imidacloprid

Imidacloprid (IDP) residue in modern agricultural production seriously endangers human health and environmental safety. The establishment of a rapid and efficient method for the detection of IDP residue can effectively prevent its harm to human health. Herein, we demonstrate the carbon cloth (CC) prepared by a high-temperature annealing strategy possesses enhanced electrochemical performance, which could be directly used in electrochemical IDP sensing. Annealed carbon cloth (ACC) is endowed with higher defects, rougher surfaces, more functional groups, more hydrophilic surface, and increased ion-accessible surface area. Furthermore, the ACC electrode shows superior electrocatalytic reduction activity towards IDP, possessing a wide linear range of 5-100 μM, a low detection limit of 0.04 μM, and high sensitivity of 35.58 μA mM^-1 cm^-2. Meanwhile, this sensor can be applied for sensing IDP in grapes and apples with a good recovery of 96.8-104.1%. Compared with other modified electrodes, the ACC electrode has the advantages of no binder, no complicated modification, excellent detection effect, low cost, and easy large-scale production. Consequently, this work designs a self-supporting metal-free electrode with high electrochemical performance, providing a new idea for the development of environmentally friendly IDP sensors.

Mixed-Ligand-Regulated Self-Enhanced Luminous Eu-MOF as an ECL Signal Probe for an Oriented Antibody-Decorated Biosensing Platform

The self-luminescence behavior of lanthanide MOFs (Ln-MOFs) due to the unique antenna effect is considered to be a promising electrochemiluminescence (ECL) emission for biosensors. It is more challenging for Ln-MOFs on account of the difficulty to stimulate Ln ions with the desired energy-transfer efficiency to produce stronger ECL emissions at a low potential. Here, guided by a second ligand-assisted energy-transfer strategy, we present an efficient self-enhanced luminescence mixed-ligand Eu-MOF as an ECL signal probe for an oriented antibody-decorated biosensing platform with a low detection limit and a broad detection range. Diamino terephthalic acid (NH₂-H₂BDC) and 1,10-phenanthroline (Phen) were selected as the first and second ligands, respectively, to form highly conjugated structures, as well as suppress the nonradiative energy transfer. Impressively, Phen precisely adjusts the energy gap between the triplet ligand and the excited state of Eu³⁺, realizing the self-enhancement of ECL efficiency of the Eu-MOF. The mixed ligand adjusted the molar ratio to obtain the stable and strong ECL signal at a lowered triggering potential (0.83 V). In addition, FeCo@CNT features densely active FeCo sites along with a rich hierarchy conductive carbon nanotube (CNT) network, which is efficiently a co-reaction accelerator to produce more TPA^•+ radicals to accelerate the reduction process of the Eu-MOF for achieving the ECL emission amplification. FeCo@CNT with heptapeptide HWRGWVC (HWR) constructed a matrix biosensing interface that allowed the fragment antigen-binding (Fab) regions to target specific antigens and enhance the incubation efficiency. The present study has gone some way toward designing a self-enhanced luminous Eu-MOF, thus giving new fresh impetus to develop high-performance ECL emitters for biological analysis.

Signal-enhanced electrochemiluminescence strategy using iron-based metal-organic frameworks modified with carboxylated Ru(II) complexes for neuron-specific enolase detection

The preparation of highly efficient electrochemiluminescence (ECL) illuminants is an effective method to improve the sensitivity and repeatability of ECL immunoassay. In this study, we prepared an ECL immunoassay for efficient and sensitive detection of neuron-specific enolase (NSE) by linking carboxylated Ru(bpy)₃²⁺ to an iron-based metal-organic framework (NH₂-MIL-88 (Fe)) via an amide bond as an ECL signal probe. NH₂-MIL-88 (Fe) possesses a large number of amino groups that can catalyze the co-reactant S₂O₈^2-, which generates abundant reaction intermediates SO₄^•- around Ru(dcbpy)₃²⁺, reduces the loss of material transport and energy transfer between SO₄^•- and Ru(dcbpy)₃²⁺, and significantly enhances the ECL signal. We used polyaniline-intercalating vanadium oxide (PVO) nanosheets as the substrates to capture NSE owing to the large specific surface area and extraordinary conductivity of the nanosheets. Similarly, PVO nanosheets also possess abundant amino groups, which can act as co-reaction promoters to catalyze the reaction of S₂O₈^2- to SO₄^•-, enhancing the ECL signal of the immunoassay. Therefore, we constructed a dual-enhanced ECL immunoassay with Ru(dcbpy)₃²⁺/NH₂-MIL-88 (Fe) and PVO as the signal probe and substrate, respectively, which exhibited excellent sensitivity and selectivity for detecting NSE. This study offers an effective strategy for ultrasensitive detection of trace proteins using ECL immunoassays.

Enhancing Electrochemiluminescence Efficiency through Introducing Atomically Dispersed Ruthenium in Nickel-Based Metal-Organic Frameworks

The successful application of electrochemiluminescence (ECL) in various fields required continuous exploration of novel ECL signal emitters. In this work, we have proposed a pristine ECL luminophor named NiRu MOFs, which owned extremely high and stable ECL transmission efficiency and was synthesized via a straightforward two-step hydrothermal pathway. The foundation framework of pure Ni-MOFs with the initial structure was layered-pillared constructed by the coordinated octahedrally divalent between nickel and terephthalic acid (BDC). The terephthalates were coordinated and pillared directly to the nickel hydroxide layers and the three-dimensional framework was formed, which had a weak ECL response strength. Then, the ruthenium pyridine complex was recombined with pure Ni-MOFs to produce NiRu MOFs and part of the introduced ruthenium was atomically dispersed in the layered-pillared structure through an ion-exchange method, which led to the ECL luminous efficiency being significantly boosted more than pure Ni-MOFs. In order to verify the superiority of this newly synthesized illuminant, an ECL immunoassay model has been designed, and the results demonstrated that it had extremely strong and steady signal output in practical application. This study realized an efficient platform in ECL immunoassay application with the limit of detection of 0.32 pg mL^-1 for neuron-specific enolase (NSE). Therefore, the approach which combined the pristine pure Ni-MOFs and the star-illuminant ruthenium pyridine complex would provide a convenient and meaningful solution for exploring the next-generation ECL emitters.

Progress and Prospects of Electrochemiluminescence Biosensors Based on Porous Nanomaterials

Porous nanomaterials have attracted much attention in the field of electrochemiluminescence (ECL) analysis research because of their large specific surface area, high porosity, possession of multiple functional groups, and ease of modification. Porous nanomaterials can not only serve as good carriers for loading ECL luminophores to prepare nanomaterials with excellent luminescence properties, but they also have a good electrical conductivity to facilitate charge transfer and substance exchange between electrode surfaces and solutions. In particular, some porous nanomaterials with special functional groups or centered on metals even possess excellent catalytic properties that can enhance the ECL response of the system. ECL composites prepared based on porous nanomaterials have a wide range of applications in the field of ECL biosensors due to their extraordinary ECL response. In this paper, we reviewed recent research advances in various porous nanomaterials commonly used to fabricate ECL biosensors, such as ordered mesoporous silica (OMS), metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and metal-polydopamine frameworks (MPFs). Their applications in the detection of heavy metal ions, small molecules, proteins and nucleic acids are also summarized. The challenges and prospects of constructing ECL biosensors based on porous nanomaterials are further discussed. We hope that this review will provide the reader with a comprehensive understanding of the development of porous nanomaterial-based ECL systems in analytical biosensors and materials science.

A novel electrochemiluminescence sensor based on a molecular imprinting technique and UCNPs@ZIF-8 nanocomposites for sensitive determination of imidacloprid

An MIT-ECL sensor for IM detection based on UCNPs@ZIF-8 nanocomposites.