As embodiment of the invention relates to a device for performing NMR or ESR analysis. The device comprises a detection unit, a magnet, and a disk having a magnetic pattern. The detection unit comprises a sample holding space for holding a sample and a microcoil for detecting NMR or ESR signals generated within the sample. The magnet generates a static magnetic field within the sample. The disk and magnetic pattern, when rotating, generate an excitation magnetic field, which, together with the static magnetic field, creates an NMR or ESR within the sample. Other embodiments of the invention encompass methods for performing NMR or ESR analysis using the device and methods of making such devices.