Advancements toward magneto immunoassays

Recently, a magneto binding assay was conducted. The operational principle is based on a 'sandwich' mode of detection, where the target analyte (Concanavalin A) becomes bound nonselectively by protein adsorption between the solid support (silica carrier particles) and the ferromagnetic label (magneto markers). A magnetic transducer was employed for the detection. The binding assay gave a linear response in the dynamic range of 0-1.9 mu M and proved to be sensitive by having a limit of detection at 250 nM. Furthermore, the relative standard deviation observed was 6.2% (n = 3). The demonstration of the 'sandwich' approach is a step towards achieving magneto immunoassays (MIA). (C) 1998 Elsevier Science S.A. All rights reserved.