Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
853455 | Procedia Engineering | 2016 | 10 Pages |
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.