5. Setting up Ultraflextreme MALDI-ToF-MS

Note: never edit the xeo file manually

• Mount ITO glass to Bruker MALDI adapter. 75mm X 50mm ITO glass mounts onto Bruker TLC plate and 100mmX75mm ITO glass mounts onto PAC adapter. Using single-sided copper tape, mount the ITO glass onto PAC adapter.

• Spot mass calibrant at the top right corner of the ITO glass and dry it, if MALDI matrix is not used as mass calibrant.

• Load the MALDI adapter with sample ITO glass into the instrument

• Start docking by pressing the Load/Eject button

• Geometry-> Choose the geometry file downloaded from macroMS. The geometry file should be in the geometry file folder used by FlexControl. (i.e. D:\Methods\GeometryFiles)

• On the Sample carrier tab -> Click Teach

• Click on the drop-down list to find the fiducial points that are named such as 'fiducial_top_right_null'. ' top right' is added automatically by macroMS and it means the fiducial is near the top right corner of the plate. For an array sample, fiducials are at the bottom of the drop down list. Choose one fiducial and press go. Using the video feed, navigate to the fiducial point by clicking on video feed window. When the fiducial mark is at the center of the target mark, press Reached. Example shown below.

  • Note that if there is any fiducial point within any target box, the fiducial points will appear at the last in the dropdown list for Teach Positions window.

• Do the same for the second and third position

• Press OK

• Click random points in the geometry map, and see if the center of the target mark does go to the individual targets

• Set up the AutoXecute method, including random walk, laser shots, etc. Note that the data analysis functionality of macroMS allows m/z range of 1000 for all of the mass spectra.

• Perform mass calibration

• AutoXecute tab-> Run->New-> Choose the current geometry file-> Next->Next->Drag&drop to create a box selecting the sample positions ->Next-> Choose the right AutoXecute method, output file folder, and Sample name ->Next->Finish.

• NOTE: At the stage for selecting target samples while setting up a new run, it easy to omit targets at one edge of the window. For example, if the area highlighted by blue rectangle is selected by mouse dragging from left to right, the samples at left the edge (in the red box) may not have been included. Add a new rectangle by pressing the Ctrl key followed by mouse click+drag to add the missed samples at the red edge. In the summary panel at the later stage, make sure if the number of the added samples equals to the expected. This step is especially important when the four corner spots of a rectangular droplet array are used as fiducials.

• Inspect the resulting window->OK->Set sequence name and save. AutoXecute tab-> Start automatic Run