Fluorescent immunoassay system

We report a fluorescent immunoassay system using inexpensive disposable capillaries for medical diagnostics. The system includes a glass capillary tube. The inner wall of the tube is coated with Zinc oxide (ZnO) nanorods for capturing antibodies in sample. The ZnO nanorods not only provide large surface areas for capturing more antibodies but also enhance fluorescent intensity improving the sensitivity of immunoassay significantly. The tube works as a reaction chamber, coupling with micro-pump system and a fluorescence detecting module, the immunoassay system enables quantitative detection biomarkers in 30 min with detection limits of 1 ng/mL and dynamic ranges 1-1000ng/ml for prostate specific antigen (PSA) in serum. The new conceptual fluorescent immunoassay system does not use the micro-chip fabricated by expensive microfabrication process but offering an inexpensive disposable tube-chamber for biomarkers detection onsite in clinic diagnostics.