Towards a Magnetic Microarray for Sensitive Diagnostics

We present proof-of-concept experiments and modeling towards a high-sensitivity magnetic microarray which “tags” a DNA fragment (or other biological samples) with a high-moment magnetic nanoparticle (NanoTag), which is in turn detected by a high-sensitivity spin valve (SV) or magnetic tunnel junction (MTJ) detector array. The detector can count the number of magnetic tags with a resolution of 1–20 magnetic NanoTags, potentially counting individual biomolecules.