Y: Magnetic control of an electrochemical microfluidic device with an arrayed immunosensor for simultaneous multiple immunoassays. Clin Chem 2007

Background: Methods based on magnetic bead probes have been developed for immunoassay, but most in-volve complicated labeling or stripping procedures and are unsuitable for routine use. Methods: We synthesized magnet core/shell NiFe2O4/ SiO2 nanoparticles and fabricated an electrochemical magnetic controlled microfluidic device for the detec-tion of 4 tumor markers. The immunoassay system consisted of 5 working electrodes and an Ag/AgCl reference electrode integrated on a glass substrate. Each working electrode contained a different antibody im-mobilized on the NiFe2O4/SiO2 nanoparticle surface and was capable of measuring a specific tumor marker using noncompetitive electrochemical immunoassay. Results: Under optimal conditions, the multiplex im