SQUID gradiometer measurement system for magnetorelaxometry in a disturbed environment

A SQUID measurement system for magneto-relaxometry (MRX) in disturbed environment is presented. It was developed for the determination of the distribution of magnetic nanoparticles in large objects like animals. The system is based on a thin film LTS SQUID gradiometer with a baseline of 5 mm and a field gradient sensitivity of about 30 fT/cmHz/sup 1/2/. The entire system is PC-controlled and includes a nonmagnetic x-y stage. A Helmholtz coil of 80 cm diameter allows the magnetization of the samples with fields up to 7 mT. First measurements in a disturbed environment are presented.