A Multimodal SIMS/MALDI Mass Spectrometry Imaging Source with Secondary Electron Imaging Capabilities for Use with timsTOF Instruments.

Mass spectrometry imaging (MSI) is a surface analysis technique that produces chemical images and is commonly used for biological and biomedical research. Multimodal imaging combines multiple imaging modes in order to get a more comprehensive view of a sample. Multimodal MSI images are often acquired using multiple MSI instruments, which leads to issues regarding image registration and increases the chance of sample damage or degradation during sample transfer. These problems can be solved by using a single instrument that can image in multiple modes. In order to improve the efficiency of multimodal imaging and investigate complementary modes of MSI, we have modified a prototype Bruker timsTOF fleX by adding secondary ion mass spectrometry (SIMS) and secondary electron (SE) imaging capabilities while preserving the ability to perform matrix-assisted laser desorption/ionization (MALDI). We show multimodal images collected on this instrument that required only trivial registration and were acquired without sample transfer between imaging trials. Furthermore, we characterize the performance of SIMS, SE, and MALDI imaging and compare the performance of the modified instrument to a commercial timsTOF fleX.

Twin trap or hyphenation of a 3D Paul- and a Cassinian ion trap.

A new, generalized form of electrostatic, harmonic ion trap mass analyzer, referred to as a Cassinian trap, was introduced in 2009. The present work couples a second order Cassinian trap with a 3D Paul trap in an effort to produce an instrument having the advantages of both (i.e., MS(n) and high mass resolution and accuracy). The present study demonstrates the trapping of ions in the 3D Paul trap and their subsequent transfer to the Cassinian trap. The simultaneous transfer of ions over a broad (factor of 13) mass range is shown. Once in the Cassinian trap, ions can be mass analyzed by Fourier transform means, producing resolving powers as high as 53,000 for the fundamental FID and 140,000 for the third harmonic in 1 s.