In the realm of electrochemiluminescence (ECL), the issue of weak signal intensity and instability linked with pure graphitic carbon nitride (CN) is widely recognized. This study suggests a method to produce nitrogen-deficient (NC) porous ultrathin CN (UACN) using ammonium acetate and ultrasonication. The ultrathin porous nature of UACN provides numerous NC defects as catalytic sites, aiding in the decomposition of KSO, a conclusion supported by density functional theory (DFT).
View Article and Find Full Text PDFThe combination of the photothermal effect and immunoassay serves as a potent tool for crafting cost-effective and user-friendly biosensing systems. To ensure efficient light-to-heat conversion, we integrated three-dimensional-printed (3D printed) technology to devise a novel design. This design functions as the structural support for both the cell phone and laser probe, as well as a means for sample handling.
View Article and Find Full Text PDFPerylene diimide (PDI) is a readily reducible electron-deficient dye that exhibits strong photoluminescent properties, providing new opportunities for synthesizing novel electrochemiluminescence (ECL) emitters. In this study, ethylene glycol (EG) was used to induce the self-assembly of PDI supramolecules for the preparation of ultrathin EG-PDI nanosheets characterized by low crystallinity and weak stacking interaction. Notably, EG-PDI integrates luminescent and catalytic functions into one device, accelerating the interfacial electron transfer and the faster charge transfer kinetics of EG-PDI with KSO.
View Article and Find Full Text PDFIn recent years, carbon nitride (CN) has attracted substantial attention in the field of electrochemiluminescence (ECL) applications, owing to its outstanding optical and electronic properties. However, the passivation of CN during the ECL process has contributed to reduced stability and poor repeatability. While some studies have tried to boost ECL performance by altering CN through doping and vacancies, effectively suppressing CN passivation at high potentials continues to be challenge.
View Article and Find Full Text PDFLuminol has garnered significant attention from analysts as one of the most effective and commonly used electrochemiluminescence (ECL) reagents. However, the efficient luminescence of luminol anode is limited by the excitation of various reactive oxygen species (ROS). Typically, ROS are generated through co-reactive reagents and dissolved oxygen.
View Article and Find Full Text PDFBy combining two different materials, metal-organic frameworks (MOF) and β-cyclodextrins (β-CD), a signal amplification electrochemical luminescence (ECL) immunosensor was constructed to realize the sensitive detection of AFP. The indium-based metal-organic framework (In-MOF) was used as the carrier of Ru(bpy), and Ru(bpy) was immobilized by In-MOF through suitable pore size and electrostatic interaction. At the same time, using host-guest recognition, β-CD enriched TPA into the hydrophobic cavity for accelerating the electronic excitation of TPA, then, achieving the purpose of signal amplification.
View Article and Find Full Text PDFConventional luminol co-reactant electrochemiluminescence (ECL) systems suffer from low stability and accuracy due to factors such as the ease of decomposition of hydrogen peroxide and inefficient generation of reactive oxygen species (ROS) from dissolved oxygen. Inspired by the luminol ECL mechanism mediated by oxygen evolution reaction (OER), the nickel-cobalt layered double hydroxide (NiCo-LDH) hollow nanocages with hollow structure and defect state are used as co-reaction promoters to enhance the ECL emission from the luminol-H O system. Thanks to the hollow structure and defect state, NiCo-LDH hollow nanocages show excellent OER catalytic activity, which can stabilize and efficiently produce ROS and enhance the ECL emission.
View Article and Find Full Text PDFCompared with the accuracy of a single signal and the limitation of environmental applicability, the application value of dual-mode detection is gradually increasing. To this end, based on the photothermal effect of Ag/Co embedded N-rich mesoporous carbon nanomaterials (AgCo@NC NPs), we designed a dual-mode signal response system for the detection of α-fetoprotein (AFP). First, AgCo@NC NPs act as a photothermal immunoprobe that converts light energy into heat driven by a near-infrared (NIR) laser and obtains temperature changes corresponding to the analyte concentration on a hand-held thermal imager.
View Article and Find Full Text PDFTo sensitively monitor trace amounts of alternariol (AOH) in fruits, a dual-mode aptamer sensor utilizing the dual-function nanomaterial PoPD/Ru-Au was developed. This sensor provides both electrochemical (EC) and electrochemiluminescence (ECL) signals, which can greatly avoid the potential false positive of the traditional single signal, thus enhancing the accuracy and reliability of detection results. Polyo-phenylenediamine (PoPD), known for its favorable EC response, can also assist in enhancing the ECL behavior of Ru-Au.
View Article and Find Full Text PDFAlpha-fetoprotein (AFP) is the best diagnostic marker for hepatocellular carcinoma (HCC) and plays an important role in the general surveillance of the population. Therefore, the establishment of an ultra-sensitive AFP assay is essential for the early screening and clinical diagnosis of HCC. In this work, we designed a signal-off biosensor for ultra-sensitive detection of AFP based on an electrochemiluminescent resonance energy transfer (ECL-RET) strategy using luminol intercalated layered bimetallic hydroxide (Luminol-LDH) as an ECL donor and Pt nanoparticles-grown on copper sulfide nanospheres (CuS@Pt) as ECL acceptor.
View Article and Find Full Text PDFThe improvement of electrochemiluminescence (ECL) intensity in luminol, a classic electrochemiluminescent material, remains a controversial topic. In this study, synthesis of acetylene black oxide (ACETO) through simple air annealing was successful in introducing oxygen-containing groups and defects, which can act as active sites for the oxygen reduction reaction (ORR) and exhibit excellent catalytic activity. By introducing the two-electron (2e) ORR into the cathode ECL system of luminol, integration of ACETO and luminol allows for in situ generation of dissolved oxygen into reactive oxygen species (ROS), thereby enhancing the ECL intensity of luminol.
View Article and Find Full Text PDFIn this paper, a novel donor-acceptor pair was creatively proposed based on the principle of electrochemiluminescence resonance energy transfer (ECL-RET): luminol immobilized on polyethyleneimine (PEI)-functionalized manganese-based single-atom nanozymes (Mn SANE/PEI-luminol, donor) and a PtCu-grafted hollow metal polydopamine framework (PtCu/h-MPF, acceptor). A quenched ECL immunosensor was constructed for the ultrasensitive analysis of carcinoembryonic antigen (CEA). Mn SANE, as an efficient novel coreaction accelerator with the outstanding performance of significantly activating HO to produce large amounts of ROS, was further modified by the coreactant PEI, which efficiently immobilized luminol to form a self-enhanced emitter.
View Article and Find Full Text PDFEffective signal amplification is a prerequisite for ultrasensitive detection by electrochemical immunosensors. For quantitative and ultrasensitive detection of alpha-fetoprotein (AFP), we designed a competitive electrochemical immunosensor and transferred the immunoreactivity from the electrode surface to the cuvette. AFP antigen was captured using AFP primary antibody (Ab) immobilized on magnetic nanobeads (MBs), and ZIF-8 nanomaterials attached to secondary antibody (Ab) were used as probes.
View Article and Find Full Text PDFIn electrochemical immunoassays, great breakthroughs have been made in ultrasensitive detection of tumor markers by amplifying signals with coreaction accelerators. Herein, carbon nitrides with nitrogen vacancies (CNNVs) are proposed as emitter, due to the introduction of nitrogen vacancies this emitter has better ECL efficiency, the phenomena of interface electron transfer and electrode passivation are improved. At the same time, it can also promote the electrochemical reduction of coreactant, making it an attractive and potential emitter.
View Article and Find Full Text PDFEffective signal amplification is a prerequisite for electrochemical immunosensors to achieve ultra-sensitive detection. In this work, we prepared a sandwich-type electrochemical immunosensor for the quantitative detection of carcinoembryonic antigen (CEA). As a base platform, Ag NPs modified aminated two-dimensional nitrogen carbide nanosheets (Ag/g-CN) have good biocompatibility and conductivity.
View Article and Find Full Text PDFThe morphology effect of cerium oxide (CeO) has always been the focus of catalysis research. Few people have reported the relationship between the morphology of CeO and electrochemical performance in sensors. In this paper, a polyaniline (PANI) matrix is used as the dispersant and stabilizer, ultrafine Au nanoparticles (NPs) (Au@PANI) are uniformly embedded in the PANI matrix, and Au NPs@PANI is fixed on the surface of CeO with different morphologies and sizes (Spindle CeO:(SCe), octahedron CeO (OCe)).
View Article and Find Full Text PDFIn this study, a novel signal-amplified immunosensor was designed by using a microwave-assisted self-assembly method to synthesize ZnFeO-Ag/rGO nanocomposites. The conductivity of ZnFeO-rGO nanocomposites was significantly improved due to the effective inhibition of rGO accumulation by the insertion of ZnFeO and Ag nanoparticles (NPs) into graphene sheets. Excellent sensitivity and reproducibility were achieved through the microwave-assisted preparation of ZnFeO-Ag/rGO nanocomposites as a substrate, with the Ag NPs enhancing the signal because of the effective conductive matrix.
View Article and Find Full Text PDFEffective treatment of cancer depends on early detection of tumor markers. In this paper, an effective template-free method was used to prepare CoS@C three-dimensional hollow sheet nanotubes as the matrix of the immunosensor. The unique three-dimensional hybrid hollow tubular nanostructure provides greater contact area and enhanced detection limit.
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