A linear slope analyzing strategy of GMR sensor transfer curve for the detection of superparamagnetic nanoparticles

摘要

Superparamagnetic nanoparticles are popular magnetic label materials for the magnetic biodetection technologies. The accurate detection of superparamagnetic nanoparticles is one of the key aspects for high performance magnetic biodetection platform. An improved detection protocol of superparamagnetic nanoparticles using giant magnetoresistance (GMR) sensors were studied in this paper. In this study, the as-synthesized iron oxide nanoparticles (IONPs) with superparamagnetic behavior were detected by GMR sensors (GF708, Sensitec GmbH). The sensor transfer curves were measured before and after depositing IONPs onto sensor surfaces. The linear range of the transfer curves were analyzed, and the change of the slope indicated the quantity of IONPs on sensor surfaces.