Ultrasensitive Detection Research Articles

Dendritic copper nanostructures for ultrasensitive detection of rhodamine 6G and Congo red

Surface-Enhanced Raman Scattering (SERS) is a fast-responding and non-destructive ultra-sensitive detection technique that can replace traditional chromatographic and spectroscopic analysis techniques. In this experiment, dendritic copper nanostructures were prepared by the solid-state ionics method and the vacuum hot evaporation process with an applied current of I=9μA. Using them as a SERS substrate, Raman detection was performed on the dye molecules Rhodamine 6G (R6G) and Congo Red (CR) to determine SERS enhancement performance. It is found that the growth of the prepared copper nanostructures has a top-end dominant phenomenon. The fractal dimension of the copper nanostructure was calculated using fractal theory, and it was revealed to be 1.560. Scanning electron microscopy (SEM) results showed that a large number of 60-80 nm regularly arranged copper nanoparticles were attached to the surface of the dendritic copper nanostructure. This is beneficial to increase the surface roughness of the substrate and improve the detection level of dye molecules. Subsequently, copper nanostructures can sensitively detect R6G and CR solutions as low as 1×10-13 mol/L and 1×10-7 mol/L, reaching single-molecule levels. The Raman mapping experiment showed that the mean relative standard deviation (RSD) values of R6G and CR were 12.3% and 12.9%, indicating high uniformity and reproducibility of the structure. This structure effectively achieves the fusion of uniformity, repeatability, and sensitivity, and shows broad application prospects in food detection.

Biosensor based on MXene-Y2O3 composite for ultrasensitive detection of catechol in water samples

Biosensor based on MXene-Y2O3 composite for ultrasensitive detection of catechol in water samples

Advanced functional carbon electrode for ultra-sensitive detection of hexavalent chromium in water: Performance, mechanism, and application

Accurate and rapid detection of trace Cr(VI) in water is essential for environmental pollution control and human health protection. In this study, we developed a novel electrochemical sensor co-modified with polyaniline-functionalized Fe3O4 nanoparticles and a Ce-based metal–organic framework (Ce-MOF). The unique interface morphology and outstanding electrocatalytic properties of the modified electrode enabled ultra-sensitive detection of Cr(VI), with excellent linearity in the range of 1 to 1000 μg/L and a limit of detection (LOD) of 0.05 μg/L. Combined with DFT and XPS analysis, the catalytic mechanism of the Ce and Fe bimetals for Cr(VI) detection was deeply investigated. The Cr d-orbitals are hybridized with Fe d-orbitals and O p-orbitals around −5.0 eV, indicating strong electronic coupling between Cr atoms and Fe/O atoms is achieved based on the optimized model structure (Fe3O4/Ce-MOF/Cr). Additionally, Ce facilitated the valence cycling of Fe, promoting Fe2+ generation and enhancing electron donation, which in turn improved the reduction of Cr(VI). Significantly, we firstly integrated this composite with laser-induced graphene technology to create flexible integrated electrodes that meet practical requirements, breaking through the previous limitations of poor portability and expanding application scenarios. This study provides new insights for accurate, efficient, and portable on-site detection of Cr(VI) in water environments.

Noncontact 3D Bioprinting of Proteinaceous Microarrays for Highly Sensitive Immunofluorescence Detection within Clinical Samples.

Immunofluorescence assays are extensively used for the detection of disease-associated biomarkers within patient samples for direct diagnosis. Unfortunately, these 2D microarrays suffer from low repeatability and fail to attain the low limits of detection (LODs) required to accurately discern disease progression for clinical monitoring. While three-dimensional microarrays with increased biorecognition molecule density stand to circumvent these limitations, their viscous component materials are not compatible with current microarray fabrication protocols. Herein, we introduce a platform for 3D microarray bioprinting, wherein a two-step printing approach enables the high-throughput fabrication of immunosorbent hydrogels. The hydrogels are composed entirely of cross-linked proteins decorated with clinically relevant capture antibodies. Compared to two-dimensional microarrays, these proteinaceous microarrays offer 3-fold increases in signal intensity. When tested with clinically relevant biomarkers, ultrasensitive single-plex and multiplex detection of interleukin-6 (LOD 0.3 pg/mL) and tumor necrosis factor receptor 1 (LOD 1 pg/mL) is observed. When challenged with clinical samples, these hydrogel microarrays consistently discern elevated levels of interleukin-6 in blood plasma derived from patients with systemic blood infections. Given their easy-to-implement, high-throughput fabrication, and ultrasensitive detection, these three-dimensional microarrays will enable better clinical monitoring of disease progression, yielding improved patient outcomes.

Ultrasensitive Biosensors Detecting m6A in Blood: Achieving Early Screening and Typing of Tumors.

N6-methyladenosine (m6A) modification is one of the most widespread RNA modifications in eukaryotes and is involved in cancer development and progression by regulating oncogene expression. Herein, a reticulated rolling circle amplification (RCA) cascade reaction was used to construct a novel electrochemical biosensor for ultrasensitive detection of m6A, employing ferrocene-tyramine (Fc-Tyr) molecules as electroactive probes. In this strategy, the RCA cascade reaction not only amplifies specific circular DNA in the designed template to reduce the binding with similar nucleic acid sequences but also generates a long ssDNA through multiple repetitions to capture a large number of electrochemical signal probes and achieve the amplification of electrochemical biosensing signals. The developed biosensor demonstrated high selectivity and sensitivity toward m6A in the range of 0.5 pM-150 nM, with a detection limit of 14.07 fM. Meanwhile, total RNA extracted from cell samples was analyzed for m6A expression levels using the developed biosensor and a commercial colorimetric immunoassay, the biosensor and immunoassay showed consistent results. In addition, m6A levels in clinical serum samples were assessed using the developed electrochemical biosensor, which showed that m6A expression was much lower in healthy individuals than in cancer patients, therefore the biosensor is promising for cancer typing. This study provides a new method for rapid and convenient tumor marker detection in clinical practice, as well as a new idea for sensitive detection of other biomolecules.

Optimizing SureQuant for Targeted Peptide Quantification: a Technical Comparison with PRM and SWATH-MS Methods.

Bacterial infections are a major threat to human health worldwide. A better understanding of the properties and physiology of bacterial pathogens in human tissues is required to develop urgently needed novel control strategies. Mass spectrometry-based proteomics could yield such data, but identifying and quantifying scarce bacterial proteins against a preponderance of human proteins is challenging. Here, we explored the recently introduced SureQuant method for highly sensitive targeted mass spectrometry. Using a major human pathogen, the Gram-positive bacteria Staphylococcus aureus, as an example, we evaluated several parameters, including the number of targets and intensity thresholds, for optimal qualitative and quantitative protein analysis. By comparison, we found that SureQuant achieved the same quantitative performance as standard parallel reaction monitoring while allowing accurate and precise quantification of up to 400 targets. SureQuant also surpassed the sensitivity and quantification capabilities of global data-independent acquisition methods. Finally, to facilitate method development, we provide optimized MS parameters for the sensitive quantification of different peptide panel sizes. This study provides a foundation for the broader application of SureQuant in the analysis of clinical specimens containing trace amounts of bacterial proteins as well as other studies requiring ultrasensitive detection of low-abundant proteins.

Pump-free SERS microfluidic chip based on an identification-competition strategy for ultrasensitive and efficient simultaneous detection of liver cancer-related microRNAs

In this study, we present a pump-free SERS microfluidic chip capable of detecting liver cancer-related miR-21 and miR-155 concurrently with ultra-sensitivity and high efficiency. We employed a Fe3O4@cDNA-AuNPs@Raman reporter@H composite structure and a recognition competition strategy. When the target miRNAs (miR-21 and miR-155) are present in the test liquid, they specifically compete with the nucleic acid complementary strand(H) of Fe3O4@cDNA-AuNPs@Raman reporter@H, causing AuNPs to competitively detach from the surface of Fe3O4, resulting in a decrease in the SERS signal. Consequently, this pump-free SERS microfluidic chip enables the detection of the target miRNAs more rapidly and accurately in complex environments. This method offers an approach for the simultaneous and efficient detection of miRNAs and holds promising applications in the early diagnosis of liver cancer.

A Clickase-Mediated Immunoassay Based on Nanopore and Bionic Signal Labels for Ultrasensitive, Portable, and On-Site Detection of Ricin.

It is of particular importance to develop an effective method that possesses several merits simultaneously of rapid, ultrasensitive, portable, and on-site detection potential for food safety detection. Herein, we propose a clickase-mediated immunoassay based on nanopore and bionic signal labels for the detection of ricin. The introduction of Cu/Cys clickase and nanopore simultaneously effectively addressed the inherent limitations of natural enzymes and colorimetric signal output, respectively. Using this method, bionic signal labels can be easily formed through DNA and Gram-positive bacterial cell wall terminal peptide fragments (labeled by alkynyl and azide, respectively) and vancomycin. Translocation of the D-P@vancomycin through the nanopore generated highly specific oscillation current traces. This method showed a great on-site detection potential and superior analytical performance owing to the combination of the specificity of antibodies, high CuAAC click reaction catalytic efficiency of clickase, ultrasensitivity of the nanopore, and high signal resolution of D-P@vancomycin. Moreover, the practical applicability of the established method was also verified, achieving a limit of detection (LOD) down to 200.9 ag/mL with a wide linear relationship under the optimized conditions. In conclusion, this method is promising for rapid, portable, ultrasensitive, and on-site food safety detection.

MNPs-aptazymes-PtNPs molecular motor biosensor mediated by circular cleavage reactions for the ultrasensitive detection of aflatoxin B1 in real samples

As a significant food safety risk factor linked to cancer, liver diseases, and kidney diseases, aflatoxin B1 (AFB1) necessitates rapid and ultrasensitive detection to mitigate its associated high morbidity and mortality rates. In this study, we developed an advanced biosensor for AFB1 detection by optimizing magnetic nanoparticles (MNPs), platinum nanoparticles (PtNPs), and aptazymes. The resulting MNPs-aptazymes-PtNPs molecular motor biosensor demonstrates promising capabilities for AFB1 detection. Initially, the specific binding between AFB1 and a split aptamer pair facilitates the conversion of intermolecular hybridization of DNAzyme strands into intramolecular hybridization on the MNPs surface. Then the catalytic strands of DNAzyme cleave substrate strands, resulting in PtNPs-containing fragments being released from the MNPs surface and enabling the molecular motor’s movement. The extensive cleavage of substrate strands by the long catalytic strands and the stepwise movement on MNPs surface are driven by the target-specific binding of AFB1. With high peroxidase-mimicking activity, the released PtNPs enable AFB1 detection after short incubation period. The MNPs-aptazymes-PtNPs molecular motor exhibits a sensitivity of 98.95 % and a specificity of 100 %, with a minimum detectable concentration of 300 fg/mL. This thermostabilized, cyclic, and enzyme-free nanomachine demonstrates broad applicability for the detection of various aflatoxins due to its target-empowered, sequence-independent mechanism, possesses excellent guarantee and supervision for enormous Ganoderma products in Shandong province, China.

Strong coupling induced ultrasensitive chiral detection by metal-dielectric hybrid metasurface

Circular dichroism (CD) spectroscopy struggles to detect weak signals from small, chiral molecules due to limitations in light absorption. This study introduces a method for significantly enhancing CD signals using a metal-dielectric hybrid metasurface. The metasurface creates a superchiral hotspot that amplifies the chirality of nearby molecules. Two techniques are proposed to overcome signal cancellation between the intrinsic and induced signals to achieve an overall enhancement of the CD signal by up to 23,630 times. This approach has the potential for ultrasensitive detection of chiral molecules at the nanoscale, with applications in pharmacology, toxicology, and life sciences.

CuO@3D graphene modified glassy carbon electrode towards the detection of Orange II and Rhodamine B

Synthetic dyes are illegally used in foodstuffs and cause serious health issues in humans due to their carcinogenic nature. To avoid serious health issues, it is compulsory to detect and remove even the minute quantities of these harmful dyes in foodstuffs. Electrochemical sensors are accredited as an efficient and promising platform for the robust and sensitive determination of food toxins in various foodstuffs. Therefore, an efficient, facile, and competent sensor is devised for the simultaneous detection of Orange II (OR II) and Rhodamine B (RhB) supported by rGO and CuO nanoparticles. The synergism between rGO’s immense surface area and the adsorption properties of CuO enhances selectivity and response time for the detection of OR II and RhB. This work elaborated the synthesis, characterization, and electrochemical behavior of CuO@3DGr electrode towards simultaneous sensing of OR II and RhB. Physicochemical techniques were utilized to validate the fabrication of targeted material. On the other hand, the electrochemical features of the developed sensor were characterized by cyclic voltammetry (CV) and electron impedance spectroscopy (EIS). Differential pulse voltammetry technique was employed to detect simultaneously Orange II and Rhodamine B on the surface of bare (GCE), GO/GCE, CuO/GCE, and CuO@3DGr/GCE. Multi-analyte detection is possible with DPV, a sensitive electrochemical method. Based on each toxin’s specific electrochemical signature, the sensor may generate separate peaks by delivering a sequence of potential pulses and detecting the ensuing current. The parameters which influence the performance of the modified sensor were carefully evaluated. Under ambient conditions, the developed sensor exhibited excellent electrocatalytic activity in oxidation at 0.67 V of OR II and 0.96 V RhB with a low limit of detection 08 nM for OR II and 4.5 nM for RhB in Britton- Robinson buffer (BRB pH:7). The described methodology allowed a robust and fast analysis of food toxins in different foodstuff establishing this sensor as a novel tool for detecting food toxins. Tap water was used to analyze the practical applicability of developed electrode material and suitable results were achieved. These results showed that the as-synthesized novel electrochemical sensor has the potential for ultrasensitive determination and detection of toxins in different foodstuffs.

Dual Recognition Strategy-Based Ratiometric Electrochemical Assay for Ultrasensitive and Accurate Detection of Specific Circulating Tumor Cells.

Sensitive, specific, and accurate detection of circulating tumor cells (CTCs) is of great importance in the diagnosis and prognosis of cancer. Herein, an ultrasensitive ratiometric electrochemical biosensor was designed with a dual recognition strategy for highly specific and accurate detection of circulating MCF-7 human breast cancer cells based on gold film-modified porous organic cages loaded with ferrocene (Au/Fc@POCs) as the substrate and methylene blue-encapsulated covalent organic frameworks (MB@COFs) as the label material, producing two independent electrochemical signals from the Fc and MB probes, respectively. As the concentration of MCF-7 cells increases, the electrochemical signal of MB enhances significantly while the oxidation signal of Fc decreases remarkably. Under optimal experimental conditions, the ratios (IMB/IFc) between the double signals showed a broad dynamic range of 10 to 1 × 107 cells/mL with an effectively lower detection limit of 1 cells/mL (S/N = 3). Furthermore, the biosensor was able to accurately enumerate MCF-7 cells in human serum samples with excellent results. In this work, the developed ratiometric electrochemical biosensor offers a reliable and sensitive strategy for the quantitative determination of circulating MCF-7 human breast cancer cells as well as an effective approach for the clinical detection of rare cancer cells, especially in early stage cancer diagnosis.

Ultrasensitive Single-Molecule Biosensor by Periodic Modulation of Magnetic Particle Motion.

Ultrasensitive detection of low-abundance biomarkers by modern single-molecule technologies is critical for better diagnosis of severe diseases, but inevitable nonspecific bindings often cause fluctuations in the single-molecule counting results. Here we present an approach to improve the specificity in a single-molecule immunoassay by translating molecular binding signals into periodic nanomotion of magnetic particles. The sandwiched immunoassay is modified by using a long linker to tether one antibody onto a gold-covered substrate and a magnetic particle with another antibody coated as the reporter. By actively oscillating the particles with alternating magnetic fields, we could reliably identify specific binding through intensity fluctuation in plasmonic images of single particles. As a proof of concept, we demonstrate the detection of IFN-γ at the femtomolar level by the digital counting of specifically bound molecules. This active strategy outperforms existing passive motion-based approaches in sensitivity and speed, paving the way for disease diagnosis with low-abundance biomarkers.

Preparation and application of a new ion-imprinted polymer for nanomolar detection of mercury(II) in environmental waters

This study introduces a novel ion-imprinted polymer for the ultrasensitive detection of mercury(II) in water. The ion-imprinted polymer was synthesized via a simple bulk polymerization process using methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, morpholine-4-carbodithioic acid phenyl ester as the chelating agent, and ammonium persulfate as the initiator. The electrochemical mercury(II) sensing capability of the ion-imprinted polymer was studied via the modification of a cost-effective carbon paste electrode. A stripping voltammetric technique was utilized to quantify the analyte ions following open-circuit enrichment. Critical experimental parameters, including the nature and concentration of the eluent, solution pH, preconcentration duration, ion-imprinted polymer dosage, sample solution volume and reduction potential, were systematically studied and optimized. Under optimal conditions, the sensor exhibited a linear response in the range of 1.0 to 240.0 nM, with a low detection limit of 0.2 nM. The sensor demonstrated remarkable selectivity against potential interfering ions, including lead(II), cadmium(II), copper(II), zinc(II), manganese(II), iron(II), magnesium(II), calcium(II), sodium(I) and cobalt(II). The practical applicability of the developed method was successfully validated through the analysis of real water samples, suggesting its potential for environmental monitoring applications.

Wheat Germ Agglutinin-Modified "Three-in-One" Multifunctional Probe Driven Broad-Spectrum and Flexible Immunochromatographic Diagnosis of viruses With High Sensitivity.

The conventional lateral flow assay (LFA) fails to the demands for the accurate screening of viruses as a result of its low sensitivity of colorimetric signal output and poor universality limited by antibody pairs. Here, a magnetically assisted dual-signal output LFA platform is developed for the ultrasensitive, universal, and flexible detection of viruses. A "three-in-one" multifunctional probe (MAuDQD) is prepared using a 180nm Fe3O4 core to load numerous Au nanoparticles (NPs) and two layers of QDs, which can substantially improve the sensitivity of LFA through coupling with the effects of magnetic enrichment and colorimetric/fluorescent enhancement. Wheat germ agglutinin (WGA)-modified MAuDQD attained the broad-spectrum capture viral membrane proteins and the colorimetric/fluorescent dual-mode detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and monkeypox virus (MPXV) on the LFA strip. In the colorimetric mode, the target viruses detected directly, with the visual sensitivity reaching 0.1-0.5ngmL-1 and the fluorescent mode supported quantitative analysis of SARS-CoV-2/MPXV with limits of detection decreasing to pgmL-1 level. Practicability of the MAuDQD@WGA-LFA is verified through the detection of 33 real clinical samples, showing the proposed assay has a great potential to become a sensitive, accurate, and universal tool for on-site monitoring of viral infections.

Ultrasensitive detection of hazardous gas at room temperature enabled by MOF@MXene 0D-2D heterostructure

Achieving high sensitivity in detecting trace concentrations of toxic gases, particularly under room temperature (RT) conditions, remains a significant challenge. Herein, a 0D-2D heterostructure that can detect ppb-level H2S at RT is proposed by self-assembling cobalt-based metal–organic framework (Co-MOF) on Ti3C2Tx MXene. Co-MOFs with high specific surface areas can capture and concentrate target gas molecules, enhancing host-guest interactions and thereby boosting the selectivity and sensitivity. MXene nanosheets with high conductivity enable rapid electron transport at heterointerface, hence efficiently accelerating the reaction kinetics. Thereby, the as-prepared chemiresistive gas sensor based on Co-MOF@MXene 0D–2D heterostructure possessed excellent sensitivity against interfering gases and delivered an excellent response value of 11.1 to 400 ppb H2S at RT. The judicious design of MOF@MXene heterostructure may spur advanced hybrid material systems for superior sensing applications.

Enzyme cascade signal amplification platform with immobilized xanthine oxidase on nanozymes exhibiting enhanced POD-like activity for ultrasensitive dual-mode detection of xanthine

Xanthine (XA) metabolic disorders cause many diseases, hence early and precise XA detection is essential. Herein, a dual-mode enzyme cascade nanosensing platform based on Au/FMZIF-rGO/PCN nanomaterial with dual-emissive and high peroxidase-like (POD-like) activity was devised. The rapid electron transfer between Fe, Mn and P elements and the formation of ZIF-rGO/PCN hybrid enhanced POD-like activity. Aggregation-induced emission (AIE) effect improved fluorescence intensity of AuNCs. Furthermore, utilizing the nanozyme to immobilize xanthine oxidase (XOD) also reduced intermediate product diffusion, improving cascade efficiency and platform detection·H2O2 was catalytically decomposed to generate •OH, lowering fluorescence intensity at 627 nm and oxidizing TMB to produce blue oxTMB. So, dual-mode nanosensing platform was constructed with linear ranges for ratio fluorescence and colorimetric detection of XA spanning 0.5–200 μM and 0.5–300 μM, respectively, and corresponding LODs of 0.11 and 0.24 μM. The nanoplatform suggested promising potential for practical clinical detection of XA and other biomarkers.

A novel double-door-opening sensor for visual determination of cardiac troponin I based on DNA hydrogel and bimetallic nanozyme

Cardiac troponin I (cTnI), as a cardiac biomarker, holds significant importance in the diagnosis of acute myocardial infarction. However, the current detection methods mostly require specialized personnel and large analytical instruments, making it difficult to achieve convenient and on-site testing. This situation leads to delayed disease diagnosis and treatment, that increases patient suffering, and reduces the cure rate. This strategy presents the development of a portable visual DNA hydrogel colorimetric sensing platform based on a smartphone. Utilizing dual-mode detection with ultraviolet signals and solution colorimetry, the platform achieves ultra-sensitive and real-time detection of cTnI. Furthermore, optimization of detection conditions, such as the amount of polyacrylamide, reaction time, aptamer concentration, encapsulation of the nanozyme, incubation time, and reaction temperature, were performed based on this platform. The proposed ultraviolet and visual detection platforms exhibited good linear relationships with the signal within the ranges of 0.003 ng mL−1 to 10.00 ng mL−1 and 0.01 ng mL−1 to 7.00 ng mL−1, with detection limits of 2.57 pg mL−1 and 0.013 pg mL−1, respectively. Additionally, utilizing 3D printing technology, a portable detection device was designed and employed for the detection of cTnI concentrations in human serum samples. Whatever in the initial and spiked samples, the results showed high sensitivities. The sensitivity and convenience of the sensor in detecting cTnI make it promising for home testing of patients, with broad market prospects.

Enhanced bipolar electrode electrochemiluminescence biosensor for ultrasensitive monitoring of alkaline phosphatase activity during osteoblast differentiation by integrating electrocatalytic and enzymatic strategies

Alkaline phosphatase (ALP) is an important biomarker that reflects osteoblast activity and bone growth. Accurately detecting ALP activity is of pivotal clinical significance for the diagnosis and differentiation of bone system diseases. In this work, an enhanced bipolar electrode electrochemiluminescence (BPE-ECL) biosensor based on enzyme catalysis and electrocatalysis was proposed for ultrasensitive detection of ALP in osteoblasts. Carbon nitride nanosheets (CNNS) were utilized as electrocatalysts to facilitate the electrochemical reaction of bipyridine ruthenium (Ru(bpy)32+) and tripropylamine (TPrA) in the reporting cell. Meanwhile, in the sensing cell, the target ALP catalyzed the conversion of p-aminophenyl phosphate monohydrate into p-aminophenol (p-AP). The p-AP was subsequently oxidized at the anode of the driving electrode, producing electrons and increasing the Faradaic current of BPE. The dual-signal amplification strategy, combining electrocatalysis and enzyme catalysis, resulted in a 10-fold enhancement of the ECL intensity of Ru(bpy)32+/TPrA. The BPE-ECL biosensor achieved ultrasensitive detection of ALP with a detection limit as low as 1.9×10−6 U/L, and was successfully applied to monitor ALP activity in osteoblast cells. Additionally, a portable smartphone imaging was developed for the visual detection of ALP. This research introduces an innovative BPE-ECL biosensor for the monitoring of ALP activity and point-of-care testing (POCT) in osteoblasts in clinical settings.

A sandwich-type electrochemical sensor based on RGO-CeO2-Au nanoparticles and double aptamers for ultrasensitive detection of glypican-3.

Asandwich-type electrochemical aptasensor for ultrasensitive detection ofglypican-3 (GPC3)was constructed using GPC3 aptamer (GPC3Apt) labelled reduced graphene oxide-cerium oxide-gold nanoparticles (RGO-CeO2-Au NPs) as the signal probe and the same GPC3Apt as the capture probe. The electrochemical redox properties of CeO2 (Ce3+/Ce4+) in the RGO-CeO2-Au NPs indicate the electrochemical signals. When the target GPC3 was present, an "aptamer-protein-aptamer" sandwich structure was formed on the sensing interface due to the specific binding between the protein and aptamers, resulting in an increased electrochemical redox signal detected by differential pulse voltammetry (DPV) technique. Under optimal conditions, the established aptasensor exhibited a logarithmic linear relationship between the current response and GPC3 concentration in the range 0.001-100.0ng/mL, with a minimum detection limit of 0.74pg/mL. Using the spike-recovery tests for measurement of the human serum samples, the recovery was from 99.26 to 114.01%, and the RSD range was 3.04 to 5.34%. Furthermore, the sandwich-type electrochemical aptasensor exhibited excellent performance characteristics such as good stability, high specificity, and high sensitivity, demonstrating effective detection of GPC3 in human serum samples and can be used as a clinical detection tool for GPC3.