[Babcock_Hall]

Our interest is in LC/MS of the peptides, and we plan to work in water/acetonitrile/formic acid.  We found a number of protocols for Zip Tips (ours have C-18 packing) on-line, and we are focusing on those protocols that specify formic acid (not TFA).  I can post links to anything that we found.  (1) Are Zip Tips necessary?  (2) Given their capacity, does one obtain enough for material for one or for several LC/MS runs?  (3) Are Zip Tips reusable? (4) Does anyone have a particular paper or protocol that is particularly informative?  Thank you very much.