Aptamer Nanomesh-Driven Probabilistic Evaluation of Biomarker Interactions Enabling Ultrasensitive Protein Detection

Detection of disease biomarkers at ultratrace concentrations remains a major bottleneck in molecular diagnostics, restricted by the intrinsic limitations of aptamer affinity, the scarcity of analyte molecules, and insufficient signal amplification strategies. In this work, we report a surface-enhanced Raman scattering (SERS) sandwich assay supported by theoretical basis that addresses these challenges by integrating aptamers, nanomeshes, and reporter nanoprobes. The resulting platform enables reliable detection of biomarkers in the attomolar range, representing a significant advance in sensitivity compared to conventional aptamer-SERS assays. The aptamer-nanomesh design demonstrated robust performance in detecting rotein biomarkers in human serum, maintaining high recovery rates even in the presence of complex matrix interferences that typically hinder ultrasensitive measurements. Beyond a single target, the approach was extended to multiple protein targets, where each analyte produced distinct and quantifiable Raman signatures, underscoring the assay’s versatility and potential for multiplexing applications. By addressing the fundamental limitations of natural aptamer-target interactions and enhancing molecular signal readouts, this study advances aptamer-SERS biosensing toward practical translational applications.