Development of lectin‐based lateral flow assay for fucosylated alpha‐fetoprotein

Abstract

AbstractFucosylated alpha‐fetoprotein (AFP‐L3) is a more specific and sensitive biomarker for early diagnosis of hepatocellular carcinoma (HCC) than only the alpha‐fetoprotein (AFP) level. Rapid and simple detection of AFP‐L3 level greatly facilitates the early detection as well as the treatment of HCC, resulting in the reduction of mortality. Here, we developed a rapid and sensitive lateral flow assay (LFA) using lectin Lens culinaris agglutinin (LCA), which has a specific affinity to AFP‐L3 fraction of AFP, as a biorecognition element for determination of the fucosylation of AFP. The assay is based on a sandwich format performed on a lateral flow test strip. LCA was immobilized on the membrane as a test line (T). Quantitative detection of AFP‐L3 was achieved by measuring the green color intensity of captured gold nanoparticle conjugates on the T and control line (C) utilizing an in‐house test strip reader. The calculated absorbance obtained by the green color intensity signals proportionally increased with AFP concentrations. The developed lectin‐based LFA provided a detection limit of 0.8 ng/mL for AFP with a linear range between 1.5 and 160.0 ng/mL within an assay time of 10 min. Recoveries between 74.5% and 113.2% with relative standard deviations of 5.2%–8.7% for measuring spiked human serum were also achieved. The results reveal that the proposed assay offers a rapid, sensitive, and specific method, which is useful for development in point‐of‐care testing for early detection and treatment of HCC.