DESCRIPTION
The MassPREP on-line desalting column can effectively desalt proteins prior to LC-MS analyses. Because non-volatile salts (e.g., NaCl) cansuppress ionization of intact proteins leading to poor detection sensitivity, it is important to remove or significantly minimize the introduction ofthese compounds into the mass analyzer. The reversed-phase phenyl material contained in MassPREP on-line column successfully “traps” proteins,allowing the salts to be washed to waste prior to protein elution into the mass spectrometer. With an optimized LC-MS method, cycle times as lowas 4 minutes (for intact antibody) and 10 minutes (for reduced antibody) are achievable.