Storage of tryptic peptides

[csang]

Hi all,

Does anyone know the best method to store tryptic peptides? My tryptic peptides were resuspended from an SPE clean-up step in 0.1% TFA.

Prior to storage, I have filtered them through a 0.22um filter and kept them at -20oC. However 2 days later, I discovered there are particles (powdery stuffs) floating in the solution after thawing them at room temperature.


Thanks!!!

[Kostas Petritis]

I do not think is necessary to pass them through filter after you do SPE clean up. In general after SPE we bring them almost in dryness and store them to -20 C for short term (up to 15 days) or -80 C for longer periods.