Single-Molecule Sandwich Immunoassay for Quantification of Alpha-Fetoprotein Based on Evanescent Field-Enhanced Fluorescence Imaging

Figure 1

(a) DIC image of gold nanopatterned AFP chip with a spot diameter of 100 nm and (inner) SEM image of individual gold spots. (b) Schematic diagram of the AFP sandwich fluorescence immunoassay. (c) Schematic diagram showing the TIRFM detection system. L: laser; HL: halogen lamp; P: transmitted all-side polished dove-type prism; GNC: gold nanopatterned chip; OL: objective lens; BF: band-pass filter; C: charge-coupled device.

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