Highly Efficient Electrochemiluminescence Based on Luminol/MoS2 Quantum Dots@Zeolitic Imidazolate Framework-8 as an Emitter for Ultrasensitive Detection of MicroRNA.

Herein, a highly efficient electrochemiluminescence (ECL) emitter, luminol/MoS2 quantum dots@zeolitic imidazolate framework-8 (Lu/MoS2 QDs@ZIF-8), with a positive charge was prepared to construct a novel luminol-H2O2-MoS2 QD ternary ECL system for ultrasensitive detection of microRNA-21 (miRNA-21). The porous Lu/MoS2 QDs@ZIF-8 was beneficial for reducing the accessible distance between various participants in the ternary system wherein co-reaction accelerator MoS2 QDs promoted H2O2 to generate superoxide anion radicals (O2•-), which instantaneously reacted with luminol to produce robust ECL signals. Simultaneously, the positively charged Lu/MoS2 QDs@ZIF-8 facilitated the enrichment of O2•- to further improve the ECL efficiency of luminol. Impressively, compared with the traditional binary luminol-H2O2 system, the ECL efficiency of this ternary system was increased by 12.7 times. In the aid of a target-cycled and endogenous adenosine triphosphate-driven signal amplification strategy, the biosensor with Lu/MoS2 QDs@ZIF-8 as an ECL emitter achieved ultrasensitive detection for miRNA-21 with a detection limit of 14.6 aM. This work provides a promising perspective to construct a highly efficient ECL ternary system for biomolecule detection and potential disease diagnosis.

Novel Ti3C2Tx MXene nanozyme with manageable catalytic activity and application to electrochemical biosensor.

In this work, Ti3C2Tx MXene was identified as efficient nanozyme with area-dependent electrocatalytic activity in oxidation of phenolic compounds, which originated from the strong adsorption effect between the phenolic hydroxyl group and the oxygen atom on the surface of Ti3C2Tx MXene flake. On the basis of the novel electrocatalytic activity, Ti3C2Tx MXene was combined with alkaline phosphatase to construct a novel cascading catalytic amplification strategy using 1-naphthyl phosphate (1-NPP) as substrate, thereby realizing efficient electrochemical signal amplification. Taking advantage of the novel cascading catalytic amplification strategy, an electrochemical biosensor was fabricated for BCR/ABL fusion gene detection, which achieved excellent sensitivity with linear range from 0.2 fM to 20 nM and limit of detection down to 0.05 fM. This biosensor provided a promising tool for ultrasensitive fusion gene detection in early diagnosis of chronic myelogenous leukemia and acute lymphocytic leukemia. Moreover, the manageable catalytic activity of MXene broke a path for developing nanozymes, which possessed enormous application potential in not only electrochemical analysis but also the extensive fields including organic synthesis, pollutant disposal and so on.

Anodic Electrochemiluminescence of Carbon Dots Promoted by Nitrogen Doping and Application to Rapid Cancer Cell Detection.

In this work, a kind of novel nitrogen doped hydrazide conjugated carbon dots (NHCDs) with strong anodic electrochemiluminescence (ECL) at a low excitation potential were synthesized via a one-step solvothermal approach and applied to construct biosensor for rapid cancer cell detection. The nitrogen doping induced a shift of the highest occupied molecular orbital (HOMO) to the upper energy level thus lowered the anodic ECL excitation potential of carbon dots. Especially, comparing to nondoped hydrazide conjugated carbon dots, NHCDs exhibited 2.5-fold high ECL quantum efficiency because the lower potential could reduce notably the side reactions in the ECL process. Using the high-performance NHCDs to functionalize the electrode surface, a brief ECL biosensor was fabricated to detect the cell-secreted hydrogen peroxide, which could rapidly distinguish cancer cells from normal cells. What is more, the prepared NHCDs, as the combination of low excitation potential, strong ECL emission, and good biocompatibility, were expected to be popular luminophors for clinical diagnose of cancer and monitoring the pharmacodynamics of anticancer drugs.

Efficient DNA Walker Guided with Well-Regulated Interfacial Tracks for Ultrasensitive Electrochemiluminescence Biosensing.

Herein, highly efficient deoxyribonucleic acid (DNA) walking on electrode surfaces was realized by regulating DNA tracks, which was applied to construct an ultrasensitive electrochemiluminescent (ECL) biosensor for BCR/ABL fusion gene detection. The well-regulated DNA tracks were constructed via supersandwich hybridization chain reaction of two DNA strands (L1 and L2) to generate periodic linear dsDNA concatemers, where an exposed L1 domain closed with blocking strands (BS). The prepared DNA tracks were further assembled onto the surface of the Au nanoparticle-functionalized g-C3N4 nanohybrid (Au@g-C3N4 NHs)-modified electrode, achieving well-regulated interfacial tracks for the DNA walker. On this state, folic acid-labeled BS (FA-BS) were close to Au@g-C3N4 NHs, performing a quenched ECL emission. With existence of the BCR/ABL fusion gene, the target combined two walking DNA strands (WD1 and WD2) to form the bipedal DNA walkers, which walked on the well-regulated interfacial DNA tracks and replaced the FA-BS to light up the ECL emission, realizing DNA walker-based signal amplification. Compared to randomly constructed DNA tracks, the well-regulated DNA tracks reduced the kinetics barrier and fitted the step size of the DNA walker, thus promoting the DNA walking efficiency and decreasing the risk of interruption in the walking process. As a result, the designed DNA walker presented higher efficiency and capacity in signal amplification. Benefiting from this efficient DNA walker strategy, the ECL biosensor achieved sensitive detection of the BCR/ABL fusion gene with a detection limit of 0.18 fM. This smart strategy proposed a brief strategy to promote the working efficiency of the biosensor, which presented great application potential in clinical molecular diagnosis.

Perylene Derivative/Luminol Nanocomposite as a Strong Electrochemiluminescence Emitter for Construction of an Ultrasensitive MicroRNA Biosensor.

In this work, an electrochemiluminescent (ECL) biosensor was constructed on the basis of amino-modified 3,4,9,10-perylenetetracarboxylic dianhydride/luminol (PTC-NH2/Lu) nanocomposite as emitter and bipedal DNA walker signal amplification strategy for ultrasensitive detection of microRNA-21 (miRNA-21). The PTC-NH2/Lu nanocomposite was prepared as signal tag via π-π stacking molecular assembly, in which amino-modified 3,4,9,10-perylenetetracarboxylic dianhydride (PTC-NH2) as a novel coreaction accelerator significantly enhanced the ECL emission of luminol-H2O2 system. Moreover, target miRNA-21 triggered bipedal DNA walker was powered by toehold-mediated strand displacement reaction (TSDR) for signal amplification. Consequently, the proposed ECL biosensor achieved ultrasensitive detection of miRNA-21 with a linear range from 100 aM to 100 pM and a limit of detection of 33 aM. Simultaneously, the biosensor was also successfully applied to detect target miRNA-21 in lysates from human cancer cells. As a result, this work constructed a new signal amplification platform, exhibiting great application potential in biomedical analysis and early clinical diagnostics.

Novel Ru(bpy)2(cpaphen)2+/TPrA/TiO2 Ternary ECL System: An Efficient Platform for the Detection of Glutathione with Mn2+ as Substitute Target.

A sensitive electrochemiluminescence (ECL) biosensor was developed for glutathione (GSH) detection based on a novel Ru(bpy)2(cpaphen)2+/TPrA/TiO2 ternary ECL system with Mn2+ as substitute target for signal amplification. Specifically, the TiO2 nanoneedles (TiO2 NNs) were used as the coreaction accelerator for the first time to promote the oxidation process of coreactant tripropylamine (TPrA) in the anode and significantly increase the ECL signal of Ru(bpy)2(cpaphen)2+ for an amplified initial signal. Meanwhile, a novel target conversion strategy for GSH was developed by reducing MnO2 nanosheets to Mn2+ as a substitute target, which played the role of a coenzyme factor for cleaving DNA double strands intercalated with Ru(bpy)2(cpaphen)2+ to markedly weaken initial signal. As a result, the novel "on-off" biosensor achieved a sensitive detection of GSH range from 5 µM to 215 µM with a detection limit of 0.33 µM. Importantly, the proposed strategy enriched the application of Ru complex and TPrA ECL system in bioanalytical applications, and provided a new signal amplification strategy for bioactive small molecules.

Efficient Electrochemical Self-Catalytic Platform Based on l-Cys-hemin/G-quadruplex and Its Application for Bioassay.

Commonly, in the artificial enzyme-involved signal amplification approach, the catalytic efficiency was limited by the relatively low binding affinity between artificial enzyme and substrate. In this work, substrate l-cysteine (l-Cys) and hemin were combined into one molecule to form l-Cys-hemin/G-quadruplex as an artificial self-catalytic complex for the improvement of the binding affinity between l-Cys-hemin/G-quadruplex and l-Cys. The apparent Michaelis-Menten constant ( Km = 2.615 µM) on l-Cys-hemin/G-quadruplex for l-Cys was further investigated to assess the affinity, which was much lower than that of hemin/G-quadruplex ( Km = 8.640 µM), confirming l-Cys-hemin/G-quadruplex possessed better affinity to l-Cys compared with that of hemin/G-quadruplex. Meanwhile, l-Cys bilayer could be further assembled onto the surface of l-Cys-hemin/G-quadruplex based on hydrogen-bond and electrostatic interaction to concentrate l-Cys around the active center, which was beneficial to the catalytic enhancement. Through this efficient electrochemical self-catalytic platform, a sensitive thrombin aptasensor was constructed. The results exhibited good sensitivity from 0.1 pM to 80 nM and the detection limit was calculated to be 0.032 pM. This self-catalytic strategy with improved binding affinity between l-Cys-hemin/G-quadruplex and l-Cys could provide an efficient approach to improve artificial enzymatic catalytic efficiency.

Electrochemiluminescent carbon dot-based determination of microRNA-21 by using a hemin/G-wire supramolecular nanostructure as co-reaction accelerator.

An efficient coreaction accelerator scheme is introduced in an electrochemiluminescence (ECL) based method for sensitive determination of microRNA-21. It is making use of a domino type hemin/G-wire supramolecular DNA nanostructure (where "G-wire" represents a guanine-rich DNA structure) without a base pairing dependence. A glassy carbon electrode was modified with carbon dots (prepared from fullerene) and TiO2 nanoneedles. In the first step, a first hairpin 1 (H1) binds to microRNA-21 to form the hybridized complex in solution. This is followed by a T7 exonuclease (T7 Exo)-assisted target recycling to obtain a simulated target which can unfold hairpin 2 (H2) to form a double-stranded structure. After cleavage by T7 Exo, the G-rich sequences in H2 re-fold into G-quadruplexes on the electrode to form hemin/G-wire supramolecular nanostructure with the strand 1 (S1, a custom-made G-rich sequence) and hemin. As a result, the hemin/G-wire catalyzes the reaction of peroxothiosulfate that generates ECL. Thus, the signal is strongly enhanced. The method allows for the determination of microRNA-21 with a detection limit as low as 0.1 fM. It is conceived to represent a valuable tool in cancer research. Graphical abstract The hemin/G-wire supramolecular nanostructures assembled on a carbon dot (CD)-based glassy carbon electrode (GCE), thereby achieving electrochemiluminescence (ECL) signal amplification of the CD/S2O82- system and sensitive detection of microRNA-21.

Hollow Porous Polymeric Nanospheres of a Self-Enhanced Ruthenium Complex with Improved Electrochemiluminescent Efficiency for Ultrasensitive Aptasensor Construction.

Although Ru(II)-complex-based bulk nanomaterials have received considerable attention in electrochemiluminescent (ECL) assays owing to their strong ECL signals, the ECL efficiency of these nanomaterials was quite low since the bulk nanomaterials brought about a serious inner filter effect and excess inactive emitters. Herein, hollow porous polymeric nanospheres of a self-enhanced ruthenium complex (abbreviated as Ru-HPNSs) were prepared with a polyethylenimine-ruthenium complex precursor to greatly decrease the inner filter effect and minimize inactive emitters, which significantly improved the ECL efficiency. On the basis of the novel Ru-HPNSs as efficient ECL tags and target-catalyzed hairpin hybridization as signal amplification strategy, an ultrasensitive ECL aptasensor was constructed for the detection of mucin 1 (MUC1), which showed excellent linear response to a concentration variation from 1.0 fg/mL to 100 pg/mL with the limit of detection down to 0.31 fg/mL. It is worth mentioning that this work opened a new avenue for developing high-performance ECL nanomaterials as well as ultrasensitive ECL biosensors for clinical and biochemical analysis.

MoS2 Quantum Dots as New Electrochemiluminescence Emitters for Ultrasensitive Bioanalysis of Lipopolysaccharide.

Cd-based semiconductor quantum dots (QDs) with size-tunable luminescence and high quantum yield have become the most promising electrochemiluminescence (ECL) emitters. However, their unavoidable biotoxicity limited their applications in bioassays. Here, the nontoxic and economical MoS2 QDs prepared by chemical exfoliation from the bulk MoS2 were first investigated as new ECL emitters, and then the possible luminescence mechanism of MoS2 QDs was studied using ECL-potential curves and differential pulse voltammetry (DPV) methods in detail. With MoS2 QDs as the ECL emitters and triethylamine (TEA) as the efficient coreactant, a practical and label-free aptasensor for lipopolysaccharide (LPS) detection was constructed based on aptamer recognition-driven target-cycling synchronized rolling circle amplification. Comparing to conventional stepwise reactions, this target-cycling synchronized rolling circle amplification achieved more efficient signal amplification and simpler operation. The developed assay for LPS detection demonstrated a wide linear range of 0.1 fg/mL to 50 ng/mL with limit of detection down to 0.07 fg/mL. It is worth mentioning that MoS2 QDs with stable ECL emission exhibited a great application potential in ECL bioanalysis and imaging as a new type of excellent emitter candidates.

K-junction structure mediated exponential signal amplification strategy for microRNA detection in electrochemiluminescence biosensor.

Based on the novel designed K-junction structure, an economic and efficient exponential signal amplification strategy with simple protocol combining hemin/G-quadruplex, a mimetic peroxidase, as a catalyzer was proposed and utilized in an electrochemiluminescence biosensor for sensitive microRNA detection. It was noteworthy that the K-junction structure was formed with guanine-rich reporter DNA and substrate DNA modified by phosphate at the 5'-terminus. Thus, the activity of the reporter DNA could be inhibited and the recognition domain for the target microRNA constructed through the K-junction structure formed. When the target microRNA was sensed, the paired domains of the substrate DNA was completely digested from the 5'-terminus, accompanied by the release of the target microRNA and unpaired DNA fragment of the substrate DNA called the trigger DNA. Afterwards, the released microRNA and trigger DNA were recycled over and over causing the linear and exponential digestion of the K-junction structure, respectively. As a result, numerous uninhibited reporter DNAs were left on the electrode to capture hemin with the yielded hemin/G-quadruplex, which could enhance the ECL emission significantly due to its catalysis for the luminol-H2O2. As expected, this method exhibited excellent specificity and high sensitivity for microRNA detection from 0.033 fM. What's more, the application in human lung cancer cell lines achieved good sensitivity for 10 tumor cells.

In Situ Electrochemical Generation of Electrochemiluminescent Silver Naonoclusters on Target-Cycling Synchronized Rolling Circle Amplification Platform for MicroRNA Detection.

On the basis of a novel target-cycling synchronized rolling circle amplification (RCA) as a signal amplification strategy and in situ electrochemical generation of silver nanoclusters (Ag NCs) as signal probes, an ultrasensitive and simple electrochemiluminescence (ECL) biosensor was proposed for microRNA (miRNA) detection. It was worth mentioning that the circular template was subtly designed to consist of a guanine-rich (G-rich) region and a binding region for realizing target-cycling synchronized RCA. In the presence of target miR-21, the binding region hybridized with the primer and the target miR-21 to form a ternary "P" junction structure, and then the RCA was triggered from the 3'-end of the primer. Along with the proceeding of RCA, the target miR-21 was released and participated into another trigger of the RCA. On account of the G-rich region in the circular template, the product DNA of the target-cycling synchronized RCA possessed tandem periodic cytosine-rich (C-rich) sequences, which acted as ligands to further in situ electrochemically generate silver nanoclusters (Ag NCs) as ECL signal probes. As expected, the obtained ECL intensity dependent on the amount of the Ag NCs, which was positively related to the concentration of the target miR-21. The ECL assay for miR-21 detection demonstrated excellent linear response to a concentration variation from 100 aM to 100 pM and limit of detection down to 22 aM.

Cu Nanoclusters: Novel Electrochemiluminescence Emitters for Bioanalysis.

Cu nanoclusters (Cu NCs), which emerged as a new class of nontoxic, economic, and excellent phosphors and catalysts, have attracted increasing interest for a wide variety of promising applications in biolabeling and biocatalysis. However, the electrochemiluminescence (ECL) behavior of Cu NCs has never been reported in previous works. Here, anodic and blue ECL emission of Cu NCs was observed for the first time with the efficient coreactant of hydrazine (HZ), and the possible luminescence mechanism of Cu NCs/HZ ECL system was studied in detail. Briefly, HZ was oxidized, and Cu NCs got the energy to generate excited state Cu NCs* for light radiation. Furthermore, a highly sensitive "signal-off" sensing platform for the determination of dopamine has been developed upon effectively quenching of dopamine toward the Cu NCs/HZ-based ECL system. As a result, this proposed method for dopamine detection possesses high selectivity, good stability, and excellent sensitivity with a detection limit down to 3.5 × 10-13 M. This indicates that Cu NCs show potential for applications in ECL bioanalysis as a new type of low-cost and superior luminophore candidates.

Signal-off Electrochemiluminescence Biosensor Based on Phi29 DNA Polymerase Mediated Strand Displacement Amplification for MicroRNA Detection.

A target induced cycling strand displacement amplification (SDA) mediated by phi29 DNA polymerase (phi29) was first investigated and applied in a signal-off electrochemiluminescence (ECL) biosensor for microRNA (miRNA) detection. Herein, the target miRNA triggered the phi29-mediated SDA which could produce amounts of single-stranded DNA (assistant probe) with accurate and comprehensive nucleotide sequence. Then, the assistant probe hybridized with the capture probe and the ferrocene-labeled probe (Fc-probe) to form a ternary "Y" structure for ECL signal quenching by ferrocene. Therefore, the ECL intensity would decrease with increasing concentration of the target miRNA, and the sensitivity of biosensor would be promoted on account of the efficient signal amplification of the target induced cycling reaction. Besides, a self-enhanced Ru(II) ECL system was designed to obtain a stable and strong initial signal to further improve the sensitivity. The ECL assay for miRNA-21 detection is developed with excellent sensitivity of a concentration variation from 10 aM to 1.0 pM and limit of detection down to 3.3 aM.

Clinical risk prediction using language models: benefits and considerations.

OBJECTIVE: The use of electronic health records (EHRs) for clinical risk prediction is on the rise. However, in many practical settings, the limited availability of task-specific EHR data can restrict the application of standard machine learning pipelines. In this study, we investigate the potential of leveraging language models (LMs) as a means to incorporate supplementary domain knowledge for improving the performance of various EHR-based risk prediction tasks. METHODS: We propose two novel LM-based methods, namely "LLaMA2-EHR" and "Sent-e-Med." Our focus is on utilizing the textual descriptions within structured EHRs to make risk predictions about future diagnoses. We conduct a comprehensive comparison with previous approaches across various data types and sizes. RESULTS: Experiments across 6 different methods and 3 separate risk prediction tasks reveal that employing LMs to represent structured EHRs, such as diagnostic histories, results in significant performance improvements when evaluated using standard metrics such as area under the receiver operating characteristic (ROC) curve and precision-recall (PR) curve. Additionally, they offer benefits such as few-shot learning, the ability to handle previously unseen medical concepts, and adaptability to various medical vocabularies. However, it is noteworthy that outcomes may exhibit sensitivity to a specific prompt. CONCLUSION: LMs encompass extensive embedded knowledge, making them valuable for the analysis of EHRs in the context of risk prediction. Nevertheless, it is important to exercise caution in their application, as ongoing safety concerns related to LMs persist and require continuous consideration.

Insight into selectivity of photocatalytic methane oxidation to formaldehyde on tungsten trioxide.

Tungsten trioxide (WO3) has been recognized as the most promising photocatalyst for highly selective oxidation of methane (CH4) to formaldehyde (HCHO), but the origin of catalytic activity and the reaction manner remain controversial. Here, we take {001} and {110} facets dominated WO3 as the model photocatalysts. Distinctly, {001} facet can readily achieve 100% selectivity of HCHO via the active site mechanism whereas {110} facet hardly guarantees a high selectivity of HCHO along with many intermediate products via the radical way. In situ diffuse reflectance infrared Fourier transform spectroscopy, electron paramagnetic resonance and theoretical calculations confirm that the competitive chemical adsorption between CH4 and H2O and the different CH4 activation routes on WO3 surface are responsible for diverse CH4 oxidation pathways. The microscopic mechanism elucidation provides the guidance for designing high performance photocatalysts for selective CH4 oxidation.

Hydrangea-like AuPtRu/ZnO-rGO Nanocomposites with Enhanced Peroxidase Mimiking Activity for Senitive Colorimetric Determination of H2O2.

In this study, a facile and cost-effective hydrothermal synthesis method was used to synthesize zinc oxide nanoflowers modified by reduced graphene oxide, and subsequently, trimetallic AuPtRu nanoparticles(AuPtRuNPs) were supported via the reduction method for high-sensitivity colorimetric detection of H2O2 in weakly acidic solutions. Compared to monometallic and bimetallic nanoparticles, trimetallic nanoparticles exhibit significant synergistic effects and enhanced catalytic activity. After providing a three-dimensional structure with multiple pores by zinc oxide and enhancing electron transfer ability by reduced graphene, the trimetallic nanocomposites (AuPtRu/ZnO-rGO) exhibited excellent peroxidase-mimicking activity, which can effectively catalyze 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue oxidation product (oxTMB) in the presence of H2O2. Compared to horseradish peroxidase (HRP), AuPtRu/ZnO-rGO demonstrated significantly enhanced catalytic velocity (Vmax = 6.16 × 10-8 M/s) and affinity (Km = 0.02) for H2O2. The study of the catalytic mechanism showed that trimetallic Au, Pt, and Ru could effectively catalyze H2O2 to produce hydroxyl radicals (•OH) to accelerate the oxidation of TMB and enhance the peroxidase-mimicking activity of the AuPtRu/ZnO-rGO nanocomposites. The results showed that the as-synthesized hydrangea-like AuPtRu/ZnO-rGO nanocomposites showed enhanced peroxidase-mimicking activity. It could be used for the colorimetric detection of H2O2 in the range 5-1000 µM with a LOD of 3.0 µM (S/N = 3), and the recoveries are 93.0-101.7%. In addition, the AuPtRu/ZnO-rGO nanocomposites have good applicability for sensitive colorimetric determination of H2O2 in milk, and it has broad application prospects as a multifunctional sensing platform in the food processing industry.

PdPtRu trimetallic nanozymes and application to electrochemical immunosensor for sensitive SARS-COV-2 antigen detection.

Herein, a ternary PdPtRu nanodendrite as novel trimetallic nanozyme was reported, which possessed excellent peroxidase-like activity as well as electro-catalytic activity on account of the synergistic effect between the three metals. Based on the excellent electro-catalytic activity of trimetallic PdPtRu nanozyme toward the reduction of H2O2, the trimetallic nanozyme was applied to construct a brief electrochemical immunosensor for SARS-COV-2 antigen detection. Concretely, trimetallic PdPtRu nanodendrite was used to modify electrode surface, which not only generated high reduction current of H2O2 for signal amplification, but also provided massive active sites for capture antibody (Ab1) immobilization to construct immunosensor. In the presence of target SARS-COV-2 antigen, SiO2 nanosphere labeled detection antibody (Ab2) composites were introduced on the electrode surface according sandwich immuno-reaction. Due to the inhibitory effect of SiO2 nanosphere on the current signal, the current signal was decreased with the increasing target SARS-COV-2 antigen concentration. As a result, the proposed electrochemical immunosensor presented sensitive detection of SARS-COV-2 antigen with linear range from 1.0 pg/mL to 1.0 µg/mL and limit of detection down to 51.74 fg/mL. The proposed immunosensor provide a brief but sensitive antigen detection tool for rapid diagnosis of COVID-19.

Highly sensitive electrochemical aptasensor for SARS-CoV-2 antigen detection based on aptamer-binding induced multiple hairpin assembly signal amplification.

In this work, a brief electrochemical aptasensor was developed for highly sensitive detection of SARS-CoV-2 antigen utilizing an aptamer-binding induced multiple hairpin assembly strategy for signal amplification. In the presence of SARS-CoV-2, a pair of aptamers was brought in a close proximity according to the aptamer-protein antigen binding, which initiated strand displacement reaction thereby triggering a multiple hairpin assembly to obtain long linear DNA concatemers on the electrode surface. As the fabricated hairpin probes were labeled with biotin, massive streptavidin-alkaline phosphatases (ST-ALP) could be further introduced on the electrode interface via biotin-streptavidin interaction thus generating strong electrochemical signal in electrolyte solution containing 1-naphthol phosphate. Benefiting from the non-enzymatic multiple hairpin assembly signal amplification strategy, the designed aptasensor for SARS-CoV-2 spike protein detection exhibited the wide linear range from 50 fg·mL-1 to 50 ng·mL-1 and low detection limit of 9.79 fg·mL-1. Meaningfully, this proposed electrochemical assay provided a potential application for the point of care analysis of viral diseases under ambient temperature.