Deblurring molecular images using desorption electrospray ionization mass spectrometry

Abstract

Traditional imaging techniques for studying the spatial distribution of biological molecules such as proteins, metabolites, and lipids, require the a priori selection of a handful of target molecules. Imaging mass spectrometry provides a means to analyze thousands of molecules at a time within a tissue sample, adding spatial detail to proteomic, metabolomic, and lipidomic studies. Compared to traditional microscopic images, mass spectrometric images have reduced spatial resolution and require a destructive acquisition process. In order to increase spatial detail, we propose a constrained acquisition path and signal degradation model enabling the use of a general image deblurring algorithm. Our analysis shows the potential of this approach and supports prior observations that the effect of the sprayer focuses on a central region much smaller than the extent of the spray.

Fig. 1

Original (blurred) DESI-MS image of an artesunate antimalarial drug tablet using m/z 791.

Fig. 2

Deblurred DESI-MS image using m/z 791. The peaks and valleys are sharper.

Fig. 3

Combined degradation/detection kernel P = PSF * Dtot for m/z 791.

Fig. 4

Original (blurred) DESI-MS image of an artesunate antimalarial drug tablet for m/z 407.

Fig. 5

Deblurred DESI-MS image for m/z 407.

Fig. 6

Combined degradation/detection kernel P = PSF * Dtot for m/z 407.