Determination of Carcinoembryonic Antigen by Surface-Enhanced Raman Spectroscopy Using Gold Nanobowl Arrays.

Surface-enhanced Raman scattering (SERS) based on the doubleantibody sandwich format is reported for the determination of carcinoembryonic antigen. Ordered gold nanobowl arrays were fabricated and conjugated with anticarcinoembryonic as capturing substrates, and gold nanoshells, adsorbed with 4-mercaptobenzonic acid, were modified with anticarcinoembryonic antigen as labeling tags. After the carcinoembryonic antigen was captured on ordered gold nanobowl arrays, the labeling tags were bonded to the captured carcinoembryonic antigen. The interaction of SERS substrates (ordered gold nanobowl arrays) and SERS labels (gold nanoshells) showed high sensitivity and a low detection limit for carcinoembryonic antigen. The linear dynamic range of SERS for carcinoembryonic antigen was from 5 pg/mL to 100 ng/mL with a linear relationship between carcinoembryonic antigen concentration and SERS intensity. The detection limit was 1.73 pg/mL. SERS detection may be used for other cancer biomarkers and provides potential for the clinical diagnosis of cancer biomarkers. [ABSTRACT FROM AUTHOR]