Nanostructured Biosensor of Cobalt Line Array on Permalloy Film

We fabricated bio-sensing devices based on two different stacking configurations-Co line array and Permalloy film (Ni₈₁Fe₁₉)/Co line array. Magnetic hysteresis loops were measured via vibrating sample magnetometer, the presence of the stray field induced from the magnetic particle within the cell would hinder the magnetization switching process, by analyzing the shift in switching field we can determine the presence of magnetically labeled cells. Our results showed that the presence of magnetic cell would increase the magnitude of switching field, and structure with Py film/Co line array yields a much higher change in switching field than Co line array.