Highly responsive signal-on biosensor based on autocatalytic and antifouling cell membrane gel interface for ultrasensitive immunoassay.

Cascade-driven dual-signal attenuation antifouling immunosensor for femtogram-level sensing for SCCA.

A cascade-driven dual-signal attenuation strategy that holds great promise for high‑performance electrochemical biosensing in complex biological samples.

Electronic Manipulation-Controlled Release Strategy-Driven Signal Off-On Mode for Ultrasensitive Detection of Environmental Pollutants.

Utilizing the extrinsic electronic properties of materials can trigger ECL signal response more efficiently than structural and energy level modulation. Microcystin-LR (MC-LR) is one of the most prevalent toxins in freshwater. Herein, a highly sensitive sensor was fabricated for MC-LR detection by integrating electronic regulation and controlled release strategies. For the controlled release strategy, mesoporous silica nanoparticles (MSNs) were employed as carriers to load glutathione (GSH), with their surfaces capped by DNA strands and covalently conjugated to target antigens. Upon specific binding between the antigen and its corresponding antibody, the double-stranded DNA structure was cut by the restriction enzyme DPN1 on the antibody, triggering the controlled release of GSH. The sensor substrate was composed of a MnO2 QDs-CBMAA (M-CB) hydrogel, which possessed dual functions: antifouling capability to mitigate non-specific adsorption of irrelevant proteins and quenching the EuCu NC signal by resonance energy transfer (RET). For the electronic manipulation strategy, the released GSH reacted with MnO2 QDs in the M-CB hydrogel, reducing them to Mn2+ without a quenching effect and thereby achieving efficient signal recovery. Consequently, the sensor achieved a low limit of detection (8.56 fg/mL) and a broad detection range from 10 fg/mL to 100 ng/mL. This novel electronic manipulation strategy endowed the sensor with rapid and highly efficient signal response performance, providing a feasible method for the sensitive trace detection of pollutants.

Super-antifouling electrochemical biosensor based on a biomimetic gemini zwitterionic interface for sensitive detection of therapeutic antibodies.

Biofouling, arising from the nonspecific adsorption of proteins, cells, and other biomolecules, remains a major challenge that compromises the stability and reliability of diagnostic and therapeutic platforms. To address this issue, a super-antifouling electrochemical aptasensor was developed by integrating a biomimetic "gemini" zwitterionic monomer (BSMMP) with polydopamine (PDA). The covalent assembly of BSMMP and PDA forms a multi-site anchoring layer that enables the stable functionalization of the affinity aptamer GC20. Owing to its dense hydration shell, the PDA-BSMMP hybrid interface acts as a physical barrier against nonspecific adsorption, maintaining electron-transfer stability in undiluted human serum. Differential pulse voltammetry confirmed that this interface markedly reduced biofouling-induced signal loss, limiting attenuation to less than 15%, nearly fourfold lower than that of the unmodified surface. The platform achieved a low limit of detection of 0.97 ng/mL, a broad linear range from 1 ng/mL to 100 μg/mL, and high selectivity for trastuzumab in a label-free format without secondary antibodies or additional signal amplification. Finally, this platform successfully quantified trastuzumab in serum from breast cancer patients, with results consistent with commercial ELISA kits. Overall, this super-antifouling aptasensor offers great potential for therapeutic drug monitoring, advancing zwitterionic interface-based biosensing strategies for point-of-care diagnostics.

A highly sensitive electrochemical immunosensor based on a g-C₃N₄/MgO nanocomposite for ultrasensitive detection of CYFRA21-1

A sensitive and label-free electrochemical immunosensor based on a g-C₃N₄/MgO nanocomposite-modified electrode for the selective detection of CYFRA21-1 has great promise for clinical diagnosis and point-of-care detection of lung cancer biomarkers because of its affordability, simplicity, and sensitivity.

Dual-Component Surface-Enhanced Raman Scattering Detection of Tetracycline Based on Aptamer-Regulated Catalytic Switch.

This paper presents a surface-enhanced Raman scattering sensing platform for sensitive detection of tetracycline (TTC) in food samples, in which dual-component signal enhancement is achieved by combining an aptamer-regulated catalytic switch with a structurally optimized substrate. The substrate consists of an ordered gold nanoparticle (AuNP) array conformally coated with a continuous MXene film via liquid-liquid interfacial assembly. A TTC-specific aptamer and catalytic nitrogen/silver co-doped carbon dots (CDN/Ag) are further integrated through controlled in-situ formation of AuNPs, enabling synergistic electromagnetic and chemical signal enhancement. The platform exhibits a wide linear range from 10-5 M to 10-12 M for TTC, with a limit of detection of 5.3 × 10-12 M, high selectivity, and robust performance in complex samples. Spike-recovery tests in milk yielded recoveries of 95.6%-126%, with relative standard deviations of 1.6%-5.1%, demonstrating the reliability and practical applicability of the sensor for food safety monitoring.

A Bifunctional CoFcMOF Nanozyme Enables Dual-Mode PEC-Colorimetric Immunosensing of C-Reactive Protein with Built-In Cross-Validation.