Modeling Approach to Optimize Chemical Imaging using a Continuously Moving Proximal Probe in Thermal Desorption/Secondary Ionization Mass Spectrometry

摘要

Modeled the effect of several experimental parameters including: (1) probe parameters (size, shape and desorption/extraction efficiency distribution); (2) scanning parameters (scan speed); (3) analyte-surface interactions (analyte desorption rate and signal-to-noise level). on the chemical imaging resolution accomplished by a CS-SSP. The software tool developed simulated chemical images from model optical images (320 pixel X 240 pixel greyscale bitmap files) where pixel brightness represented the surface concentration of the analyte at that coordinate. As all CS-SSPs inherently employ oversampling, analyte desorption rate must be maximized to minimize carryover between surface features in close proximity. Simulation showed that allowing only the central portion of CS-SSP (by masking the outer area of that off) to interrogate the surface results in higher chemical image resolution.