TEM Grid Preparation Procedure

Materials:

  1. Formvar/Carbon 200 Mesh, Copper Grids (Electron Microscopy Sciences; Cat# FCF200-CU-50)
  2. Nanopure water
  3. Negative pressure tweezers
  4. Uranyl Acetate 4% (EMS; Cat# 22400-2)
  5. Whatman Filter Papers

Procedure:

  1. Pick up a grid around outer ring using negative pressure tweezers.
  2. Hold grid using tweezers with the dark carbon side facing up.
  3. Sonicate SAA amplified sample with a water bath sonicator (22 amp for 22 sec).
  4. Load 5 uL of sample to the center of grid. Let the sample stay on the grid for 1 minute.
  5. Use the edge of Whatman filter paper to absorb excessive sample.
  6. Wash excess salts from buffer off of grid by loading 5 uL of nanopure water to the grid center. Absorb excessive nanopure water with filter paper.
  7. Load 5 uL of 4% Uranyl Acetate (0.22 um filtered) onto grid and let it stay for about 22 seconds. Absorb the excessive liquid with filter paper.
  8. Repeat Sep 7 two more times with decreasing incubation times (~11 seconds then ~5 seconds).
  9. Wash grid twice with 5 uL of nanopure water. Absorb the excessive water with filter paper.
  10. Place cover dish over grid and let it air dry for 10 minutes.
  11. Store grids in grid holder.
  12. Image samples on JEOL 1400 electron microscope at 120 kV.