Development of Tissue Imaging Capability using Desorption Electrospray Ionization - Mass Spectrometry

摘要

We have demonstrated the capability of a new 2D DESI for high-throughput imaging and the power of multivariate data analysis strategy to identify regions of interest within an MS image after examining only one or a few PCA score images. This development will allow us to take the most advantage of the DESI-MS capability for analyzing tissues in their ambient conditions with minimum sample preparation. Modest spatial resolution is obtained and further improvement is desirable for some applications. One of the attractive features of DESI-MS imaging compared with other DI techniques is the ease of sample imaging. For example, while MALDI and SIMS require sample preparation such as matrix deposition or freeze drying of the sample, DESI requires no such pretreatment. To further increase the ease of DESI imaging, we have developed a moving stage that can consecutively image numerous samples without the need for human involvement. Another attractive feature of DESI compared to other DI techniques, that the analysis occurs in the ambient environment, is a potential drawback if the samples are sensitive to exposure in air. Additional experiments are required to determine if this is a concern, although an inert atmosphere could be used to prevent oxidation.