Metal-Enhanced Immunofluorescence Assays For Detection Of Carcinoembryonic Antigen

Carcinoembryonic antigen (CEA) is a glycosylphosphatidylinositol cell surface anchored glycoprotein that is a well-known, broad spectrum biomarker related to various cancers and it is also an indicator of disease recurrence. In this work, metal-enhanced fluorescence (MEF) is utilized to lower the detection limit of CEA in immunofluorescence assays. Silver nanocubes (AgNCs) of 50 nm edge-length were incubated to plasmonically enhance fluorescence intensity. This increased sensor sensitivity by a factor of 6 and lowered the limit of detection to below 1 ng/mL in fluorescence detection of the antigen.