5.4.1.3. Clean up peptides

  1. Adjust pH of overnight digestion to ~2 using 10 % acetic acid.
  2. For each sample, prepare a STAGE tip (Rappsilber et al., 2007) by pushing 20 µl methanol through, followed by 20 µl 0.5 % acetic acid.
  3. Push 10 µg total peptide mass (based on original 50 µg input) through the STAGE tip.
  4. Wash each tip with 20 µl 0.5 % acetic acid.
  5. Elute the peptides from each tip into a clean microfuge tube with 10 µl 80 % acetonitrile, 0.5 % acetic acid.
  6. Evaporate the solvent from each sample in a vacuum centrifuge.