Novel inner filter effect-based near-infrared electrochemiluminescence sensor mediated by well-matched AgBr-nitrogen-doped Ti3C2 MXene and nonmetallic plasmon WO3•H2O

2D Zn-based metal-organic framework as an efficient electrochemiluminescence emitter: A novel inner filter effect-based ECL biosensor for trace detection of bisphenol A

The potential hazards of bisphenol A (BPA) to the environment have become a global concern. Herein, 2D Zn-based metal-organic framework nanosheet (2D Zn-MOF) and MnCO3 nanocomposite (Zn-MOF-MnCO3), an efficient electrochemiluminescence (ECL) probe was first synthesized and constructed for trace detection of BPA. Owing to the elimination of the aggregation-induced quenching (ACQ) effect of polycyclic aromatic hydrocarbons (PAHs), the leaf-like Zn-MOF exhibited a satisfactory ECL signal. The MnCO3, which has excellent biocompatibility, showed excellent ECL efficiency in the presence of K2S2O8. With the covalent binding of Zn-MOF and MnCO3, we demonstrated that the ECL intensity and stability of Zn-MOF-MnCO3 improved significantly. In addition, the inner filter effect (IFE) of Fe3O4-NH2 NPs toward Zn-MOF-MnCO3 had been confirmed to be the ECL quenching mechanism. Based on above strategies, the proposed ECL-IFE biosensor exhibited a trace detection ability of BPA in a wide linear range (10 fM ∼ 10 μM) with a low detection limit (4.2 fM). Further in-depth study confirmed the excellent repeatability, selectivity, and stability of sensors, which provided a fresh sensing platform for trace detection of BPA in the environment.

Emerging trends and recent advances in MXene/MXene-based nanocomposites toward electrochemiluminescence sensing and biosensing

Electrochemiluminescence (ECL) sensing systems have surged in popularity in recent years, making significant strides in sensing and biosensing applications. The realization of high-throughput ECL sensors hinges on the implementation of novel signal amplification strategies, propelling the field toward a new era of ultrasensitive analysis. A key strategy for developing advanced ECL sensors and biosensors involves utilizing novel structures with remarkable properties. The past few years have witnessed the emergence of MXenes as a captivating class of 2D materials, with their unique properties leading to exploitation in diverse applications. This review provides a comprehensive summary of the latest advancements in MXene-modified materials specifically engineered for ECL sensing and biosensing applications. We thoroughly analyze the structure, surface functionalization, and intrinsic properties of MXenes that render them exceptionally suitable candidates for the development of highly sensitive ECL sensors and biosensors. Furthermore, this study explores the broad spectrum of applications of MXenes in ECL sensing, detailing their multifaceted roles in enhancing the performance and sensitivity of ECL (bio)sensors. By providing a comprehensive overview, this review is expected to promote progress in related areas.

Novel immunosensor based on electrochemiluminescence inner filter effect and static quenching between fibrillary Ag-MOGs and SiO2@PANI@AuNPs for enabling the sensitive detection of neuron-specific enolase

Metal-organic gels (MOGs) are unique supramolecular gels that are convenient to synthesize. In this work, a cathodic electrochemiluminescence (ECL) system based on Ag-MOGs as a luminophore and K2S2O8 as a co-reactor was developed. The ECL spectrum of the Ag-MOGs overlapped significantly with the strong UV-Vis spectrum of the SiO2@PANI@AuNPs, which effectively quenched the ECL luminescence of the Ag-MOGs. Relying on the inner filter effect between Ag-MOGs and SiO2@PANI@AuNPs, a novel ECL-IFE immunosensor was developed for the detection of neuron-specific enolase (NSE). Under optimal conditions, the ECL signal of the immunosensor displayed excellent linearity over the NSE concentration range of 10 fg/mL-100 ng/mL. The limit of detection (LOD) was 2.6 fg/mL (S/N = 3) with a correlation coefficient R2 of 0.9975. The ECL immunosensor also exhibited excellent stability and reproducibility for the detection of NSE. The results reported provide a feasible concept for the development analytical methods for the detection of other clinically relevant biomarkers.