Can anyone provide me the proper program for LC/ESI/MS for tryptic digest in solution. I have literature surveyed and found different suggestions. In some cases, 100 % acetonitrile 0-40 % for 50-60 min was run and in some cases, 100 % acetonitrile was run with a gradient of 0-40 % for 40 min and then with 60 % from 40- 50 min. What is the standard program to follow the tryptic digest in solution?