Enhancement of labeled alpha-fetoprotein antibodies and antigen-antibody complexes fluorescence with silver nanocolloids

• Main Authors: Vaschenko, Svetlana, Ramanenka, Andrey, Kulakovich, Olga, Muravitskaya, Alina, Guzatov, Dmitry, Lunevich, Anatoly, Glukhov, Yuri, Gaponenko, Sergey
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2018
• Subjects: Silver Nanoparticles; DRNTU::Engineering::Electrical and electronic engineering; Pasmon-enhanced Fluorescence
• Online Access: https://hdl.handle.net/10356/89233; http://hdl.handle.net/10220/46198
• Institution: Nanyang Technological University

A model immunoassay test system is proposed based on metal enhanced photoluminescence to analyze low concentrations of alpha-fetoprotein, a tumor marker. Antigen-antibody reaction was performed on polystyrene plates coated with silver nanoparticles to increase sensitivity of fluorescent immunoassay and signal-to-noise ratio as compared to silver-free system. The proposed test system model uses layer-by-layer assembly approach, LED excitation and nanowatt photodetection set-up, so it is characterized by smaller probe volume, fast analysis and simplicity. The proposed model system offers alpha-fetoprotein detection at concentrations used in clinical practice. Photostability and photoluminescence enhancement for labeled alpha-fetoprotein antibodies on a silver substrate were found to depend on antibodies concentration. Labeled antibodies photostability on substrates was found to deviate within 20% as compared to silver-free samples whereas photoluminescence intensity enhancement is typically in the range of 6-8 times.