Versatile Electrochemiluminescence Biosensing Platform Based on DNA Nanostructures and Catalytic Hairpin Assembly Signal Amplification

Achieving rapid and highly sensitive detection of biomarkers is crucial for disease diagnosis and treatment. Here, a highly sensitive and versatile dual-amplification electrochemiluminescence (ECL) biosensing platform was constructed for target detection based on DNA nanostructures and catalyzed hairpin assembly (CHA). Specifically, when the target DNA was present, it would hybridize with the auxiliary strands (D1 and D2) to form an I-shaped nanostructure, which in turn triggered the subsequent catalytic hairpin assembly reaction to generate plenty of double-stranded DNA complexes (H1-H2). The resulting double-stranded complex could be trapped on the electrode surface and adsorbed the ECL signal probe Ru(phen)(3)(2+).We found that the I-shaped nanostructure-triggered CHA reaction had higher amplification efficiency compared with traditional CHA amplification. Thus, a sensitive signal-on ECL biosensor was constructed for target DNA detection with a detection limit of 1.09 fM. Additionally, by combining the binding properties of C-Ag+-C with an elaborately designed Ag+-helper probe, the proposed strategy could be immediately utilized for the highly sensitive and selective detection of silver ions, demonstrating the versatility of the developed biosensing platform. This strategy provided a new approach with potential applications in disease diagnosis and environmental monitoring.

Automated summary

A highly sensitive and versatile dual-amplification electrochemiluminescence (ECL) biosensing platform was developed for rapid and sensitive detection of biomarkers. The platform utilized DNA nanostructures and catalyzed hairpin assembly (CHA) to achieve high amplification efficiency. The biosensor demonstrated a detection limit of 1.09 fM for target DNA and showed selective detection of silver ions. The proposed strategy has potential applications in disease diagnosis and environmental monitoring.