Detection of microspotted carcinoembryonic antigen on a glass substrate by scanning electrochemical microscopy

Abstract

Microspots of carbinoembryonic antigen (CEA) on glass substrates were characterized by scanning electrochemical microscopy (SECM). CEA was immobilized via a sandiwch method using horseradish peroxidase (HRP)-labeled anti-CEA. The reduction current of the oxidized form of ferrocenylmethanol generated by the HRP reaction was monitored to view SECM images. This method detects as low as ∼104 CEA molecules in a single 20-μm-radius spot. © 1996 American Chemical Society.