A Robust Biosensor Based on the Pd−S Bond-Immobilized Peptide toward Antifouling Electrochemical Detection of an Alzheimer’s Disease Biomarker in Serum

. Moreover, the antifouling biosensor maintained consistent performance in buffer and serum, and clinical validation using human serum samples showed excellent agreement with the commercial ELISA kits, underscoring its accuracy and potential for real sample diagnostics. This work not only establishes a generalizable strategy for constructing stable and antifouling biosensing interfaces but also highlights the promise of Pd-S chemistry in biomolecule immobilization.