Gold Nanorods-based Immunochromatographic Strip for Rapid and Quantitative Detection of Prostate Specific Antigen

A gold nanorod (GNR)-based immunochromatographic strip was developed for rapid and quantitative detection of prostate specific antigen (PSA). GNR was used as the labeled probe and coated with sodium polyacrylate. Then the anti-PSA monoclonal antibody (dAb) was immobilized on the surface of GNR through covalent attachment to form the GNR-dAb conjugates. The mouse anti-PSA monoclonal antibody and the goat anti-mouse IgG were sprayed onto the nitrocellulose membrane as test line and control line , respectively. The resultant GNR-dAb conjugates were introduced to construct the immunochromatographic strip for the quantitative detection of PSA by a sandwich method. The proposed GNR-based immunochromatographic strip exhibited good specificity , high stability and high sensitivity. The experimental results indicated that GNR-based immunochromatographic strip showed a good linear range from 0. 1 ng/mL to 50 ng/mL with a limit of detection of 0. 1 ng/mL, and the relative standard deviation was less than 10%. The established assay could be successfully applied for PSA detection in serum, which was beneficial for early diagnosis, treatment and prognosis of prostate cancer.