METHOD FOR MEASURING MAGNETIC INFORMATION, IN PARTICULAR MAGNETIC AC SUSCEPTIBILITY, OF MAGNETIC NANOPARTICLES (MARKERS)

摘要

The invention relates to a method using an atomic force microscope for spatially determining nanoparticles in the region of the surface of a sample and measuring the magnetic information of said nanoparticles, in particular the magnetic AC susceptibility, wherein the greatest size of the nanoparticles lies between 1 nm and 100 nm and said nanoparticles have a magnetic moment. According to the invention, the aim is achieved in that the sample and the nanoparticles are excited with an alternating magnetic field. The alternating magnetic field has a frequency corresponding to one of the resonance frequencies of a magnetic tip of the atomic force microscope ranging from 1 kHz to 100 MHz and has a field strength of 50 A/m to 100 kA/m so that the total magnetic flux density in the region of the nanoparticles is changed, and the total magnetic flux density under the influence of the alternating magnetic field on the sample is determined using the magnetic tip of the atomic force microscope, wherein the vertical deflection of the magnetic tip is measured.