Thursday, July 30, 2020
By:
Another late entry! I have spent my week going to the lab at my campus, it is has finally paid off. To recap, the goal for me was to analyze methods of depositing solvents for use with LDI mass spectrometry. I wanted to get a homogeneous distribution of solute, and also wanted to minimize the spot size. With a dropper, you can make droplets on the surface but when they dry, they leave behind uneven rings. This week, I finally found a way to do this. The formula is:
- Airbrush instead of micropipette
- Use a stencil
- Raise the stencil 1.75 mm above the target plate
- Place the target plate on a hot plate heated to 150 degrees Celcius
- Use isopropyl alcohol as a solvent instead of water
- Hold the airbrush 4 cm above the stencil
When following these steps, it is possible to drastically improve spacial homogeneity and decrease spot size. The smallest size with the dropper was only about 3 mm, whereas I was able to get a diameter of 0.3 mm with the stencil. I went ahead and uploaded a side-by-side comparison between the dried-droplet method and the airbrush.
Overall, I've had a great week with my experiments and look forward to continue the research!
Alex Mikulich