DESCRIPTION (provided by applicant): The purpose of this proposal is to develop a novel tandem mass spectrometry (or MS/MS) technology for mass and structural analysis of biomolecules that could combine excellent ion isolation and fragmentation capabilities of a quadrupole ion trap (QIT) and high resolution and mass accuracy of Fourier transform (FT) ion cyclotron resonance (ICR) mass spectrometry (MS). The main feature of this technology is the use of a permanent magnet for generation of magnetic field in ICR part of the proposed instrument that will make it cost-efficient, compact in size, and affordable for many applications. The major emphasis is made on producing a homogeneous magnetic field in a maximum space volume that to a certain extent can compensate limitations imposed by the use of a lower magnetic field generated by a permanent magnet in the ICR cell (about 0.6 Tesla compared to 7-12 Tesla generated by superconductive magnets). A new permanent magnet design is suggested to achieve this goal. The new instrument is expected to have size, cost and MS/MS capabilities of commercial QIT-MS systems and the resolving power and mass accuracy exceeding that of a popular hybrid quadrupole/time-of-flight (QqTOF) MS.