Self-assembly of DNA-Tb(Ⅲ) nanoparticles for label-free lactate aptasensing

Lactate, a critical biomarker for various physiological and pathological conditions, necessitates precise quantification methods for effective disease diagnostics and monitoring. Traditional detection techniques, though effective, are often hampered by the need for complex instrumentation and procedures. Here, this study introduces a highly sensitive and selective electrochemiluminescence (ECL) aptasensor for the detection of lactate, leveraging the unique properties of DNA-terbium (Tb) nanoparticles (NPs) and aptamer technology. Specifically, in this label-free ECL sensor, DNA-Tb NPs were utilized as both ECL probes and recognition unit, which were synthesized by a simple coordination driven self-assembly of lactate aptamer ligand with terbium ions metal center. The biosensor exhibits a remarkable limit of detection (LOD) of 2.9 μ M across a linear range of 0.01 to 10 mM, demonstrating high selectivity, stability, reproducibility, and practical application potential. The work not only underscores the efficacy of DNA-Tb NPs in enhancing ECL signals but also showcases the aptamer’s role in achieving high specificity towards lactate detection. The optimization of assay conditions further elevates the biosensor’s performance, establishing it as a promising tool for the rapid, simple, and sensitive detection of lactate in various settings.