Magnetorelaxometry using Improved Giant MagnetoResistance Magnetometer

Magnetorelaxometry measurements on immobilized superparamagnetic magnetite (Fe3O4) nanoparticles in freeze-dried samples using a low-cost Improved Giant MagnetoResistance Magnetometer (IGMRM) are presented. Fits to relaxation phenomenological model based on Moment Superposition Model (MSM) are used to extract the characteristic values. Concentrations of iron down to 3.85 mu mol are identified in a 150 mu l volume from experimental measurements. Also, the extracted amplitude characteristic value confidence intervals associated to measurements and detection performances are given. (C) 2010 Elsevier B.V. All rights reserved.