Scaling Characteristics of the Magnetization Increments of Functionalized Nanoparticles Determined Using a Vibrating Sample Magnetometer for Liquid Magnetic Immunoassays

摘要

Here, scaling the normalized increment of dc magnetic susceptibility (Delta chi/chi) to a characteristic logistic function provides a foundation for characterizing unknown quantities of biomarkers. We report the scaling behavior of magnetization increments in reagents composed of biofunctionalized magnetic nanoparticles (BMNs) conjugated with biotargets for liquid magnetic immunoassays. We measured hysteresis loops and obtained the increment of magnetization (Delta M) after binding the C-reactive protein (CRP) to Fe3O4-anti-CRP. The results show that Delta M increased when the concentration of CRP increased. There was enhanced Delta M generated from magnetic clusters composed of Fe3O4-anti-CRP-CRP. The present platform is robust, easy to use, and can be applied to assays for various biomolecules for tumor markers, viruses, and proteins.