One-Step Immunoassay of Alpha-Fetoprotein Constructed by Silicon-Quantum-Dot-Loaded Porous Gold Nanoshells

Alpha-fetoprotein (AFP) is widely utilized for auxiliary diagnosis of primary hepatocellular carcinoma. Therefore, the development of a facile immunosensor is essential for clinical applications. This study aims to develop a simple immunoassay for AFP detection. By incorporating silicon quantum dots (SiQDs) into etching hollow gold nanoshells (EHGNs) via precise nanomanipulation, we designed molecular probes based on SiQDs@EHGNs complex immobilized capture antibodies, which can convert the antigen/antibody binding process into fluorescent divergence signals for AFP measurement. This strategy enabled one-step fluorescence sensing for AFP detection with a linear range of 3.125-200.0 ng/mL and LOD of 0.234 ng/mL. The detection results of 15 clinical serum real samples demonstrated a 93.7% correlation with the market-accepted ECLIA method. The proposed method take advantages of simplicity and rapid response, offering a novel approach for tumor marker analysis with significant potential.