posted on 2015-12-17, 05:01authored byMelissa K. Passarelli, Jun Wang, Amir Saeid Mohammadi, Raphaël Trouillon, Ian Gilmore, Andrew G. Ewing
An organic lateral resolution test
device has been developed to
measure the performance of imaging mass spectrometry (IMS) systems.
The device contains periodic gratings of polyethylene glycol (PEG)
and lipid bars covering a wide range of spatial frequencies. Microfabrication
technologies were employed to produce well-defined chemical interfaces,
which allow lateral resolution to be assessed using the edge-spread
function (ESF). In addition, the design of the device allows for the
direct measurement of the modulation transfer function (MTF) to assess
image quality. Scanning electron microscopy (SEM) and time-of-flight
secondary ion mass spectrometry (TOF-SIMS) were used to characterize
the device. TOF-SIMS imaging was used to measure the chemical displacement
of biomolecules in matrix-assisted laser desorption/ionization (MALDI)
matrix crystals. In a proof-of-concept experiment, the platform was
also used to evaluate MALDI matrix application methods, specifically
aerosol spray and sublimation methods.