• Take a new 6 µl aliquote of the DNA (under the hood) and put back the main DNA tube in the fridge.
• Go to the room by the E. coli lab (not on Friday morning!) with:
  • The 6 µl aliquote
  • A 10 µl pipete
  • Eventually some 5 µl of TE buffer (they migh have some).
• The machine is the NanoDrop Spectrophotometer.
• On the computer, click on "Nucleic Acid".
• Add 2 µl of (nuclease free) water to the machine's tip as you are asked to and measure.
• Clean tips (both sides) with a tissue.
• Add 2 µl of TE buffer and click on "Blank".
• Clean tips (both sides) with a tissue.
• Add 2 µl of DNA and click "Measure".
• Clean tips (both sides) with a tissue.
• Take 2 measurements per sample and average.
• Click on exit.

The important numbers are:

• 260/280 ratio, must be > 1.8
• 260/230 ratio, must be > 2 (too big, > 2.5? , might mean too much salts)
• Of course the DNA concentration.