Estimation of Density of Low-Concentration Magnetic Fluid by a Needle-Type GMR Sensor for Medical Applications

The size, shape and composition of magnetic nanoparticles make it an attractive tool in medical applications. Low concentration Dextran Magnetite (DM)® or magnetic fluid is widely used for biomedical applications. This paper reports experimental apparatus designed for testing low concentration magnetic fluid, results obtained by experimentation utilizing a simple, novel and low invasive needle-type spin-valve giant magnetoresistance (SV-GMR) sensor and numerical analysis for comparison with the experimental results obtained. Low concentration magnetic fluid weight density is estimated by the difference between the magnetic flux density inside and outside a magnetic fluid filled cavity. The results show that the proposed technique employing the needle sensor has a good potential to be used in biomedical applications such as hyperthermia therapy in cancer treatment and targeted drug delivery, for low concentration magnetic fluid weight density measurements in-vivo.