Dual‐Validation Single‐Molecule Detection of Tau Oligomers in Solid‐State Nanonet

ABSTRACT The abnormal aggregation of tau into soluble oligomers is a key pathological event in tauopathies including Alzheimer's disease. Detection of tau oligomers remains challenging due to their dynamic and heterogeneous nature, as well as the lack of reliable strategies for validating aggregation‐active species. In this study, we construct a stable functionalized solid‐state nanonet detection platform to achieve in situ monitoring of the heparin‐induced stepwise growth aggregation of tau oligomers and the verification of drug‐induced growth inhibition. Based on this platform, we propose a “recognition‐verification” dual‐confirmation strategy for high‐specificity single‐molecule detection of tau oligomers. Surface‐immobilized antibodies achieve primary target capture, while the intrinsic aggregation behavior of captured molecules serves as secondary verification to reduce false positives arising from nontarget capture or nonspecific adsorption. Furthermore, by converting the electrochemical sensing to an optical readout, we demonstrate the potential applicability of this strategy in practical detection. This dual‐confirmation strategy helps address false‐positive signals associated with nonspecific molecular interactions, enabling real‐time analysis of protein aggregation and holding promise for early diagnosis and drug screening of tau‐related neurodegenerative diseases.