Actively shielded 8 tesla magnet for FT-ICR Mass Spectrometry

Intermagnetics successfully delivered an 8 tesla magnet for Fourier Transfo rm Ion Cyclotron Resonance Mass Spectrometry (FT-ICR). This high field magn et is used by Lilly Research Laboratories for routine high-resolution and e xact mass analysis of higher molecular weight biopharmaceutical and biotech nology products such as proteins, DNA, etc. The system includes a NbTi magn et with high homogeneity and persistence, and a cryocooler refrigerated cry ostat with a low He boil off and a long refill interval. The magnet system incorporates many of the user-friendly features of Intermagnetics' line of Magnet Resonance Imaging (MRI) magnets including a compact self-shielded co nfiguration, high uniformity, nitrogen-free cryogenic technology, cold-ship pable for fast setup on site, and other features. The 100 cm long magnet ha s a 152 mm diameter horizontal room temperature bore. The achieved uniformi ty is better than 6 ppm peak-to-peak in a 50 mm diameter, 50 mm long cylind er. The guaranteed magnet persistence is better than 50 ppb/hour. The 5 gau ss line is located 1.4 m radially and 2.4 m axially from the magnet iso-cen ter, resulting in a stray field that is even closer to the cryostat than in lower field unshielded FT-ICR magnets. Liquid helium refill interval is 6 months or longer. Due to the reduced stray field, compactness and relativel y lightweight design, this magnet may be used to replace lower field, unshi elded magnets in mass spectrometry facilities.