Dual-Enhanced Lateral Flow Immunoassay: Synergizing Oriented Antibody Anchoring and Nanozyme Catalytic Amplification for Ultrasensitive Cancer Detection
Qing Yang, Wanchao Zuo, Jiaren Song, Siqi Zeng, Xiangming Meng, Zhipeng Ding, Qian‐Nan Hu, Xuhui Tan, Donghui Zhang, Jianjun Dai, Yanmin Ju
Abstract
Conventional lateral flow immunoassays (LFIAs) suffer from limited sensitivity in detecting low-abundance tumor biomarkers, primarily attributed to inefficient antibody utilization and insufficient signal intensity of nano-immunoprobes. Here, we propose a dual-enhanced LFIA integrating oriented antibody anchoring and nanozyme catalytic amplification for ultrasensitive visual detection of tumor biomarkers, denoted as DEOAN-LFIA. Bimetallic catalyst gold-platinum nanoparticles (Au@Pt NPs) were functionalized with phenylboronic acid to selectively orient antibodies via fragment crystallizable (Fc) glycans for improving antibody utilization efficiency, thereby enriching target-probe complexes on the test line (T line), realizing the first-step signal amplification. Subsequently, the elevated local concentration of Au@Pt NPs efficiently catalyzed the conversion of chromogenic substrates into colored products, further amplifying the signal from enriched probes on the T line for the second-step signal amplification. Using common tumor markers alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) as model targets, DEOAN-LFIA achieved ultrasensitive detection of picogram-level targets (50 pg/mL for AFP and 10 pg/mL for CEA) with rapid analysis within 25 min. Clinical validation with 36 human serum samples demonstrated favorable concordance with the standard clinical assay. This DEOAN-LFIA platform provides a robust ultrasensitive point-of-care tool for the early diagnosis of malignant diseases.