Investigation of newly synthesized peptides by capillary zone electrophoresis/electrospray mass spectrometry.

A series of newly synthesized peptides (M(r) = 1600-2250 Da), corresponding to portions of the extracellular domain of human granulocyte-macrophage colony stimulating factor receptor alpha subunit have been examined by capillary zone electrophoresis/electrospray-mass spectrometry (CZE/ES-MS). The separation efficiency of CZE combined with the specificity of mass spectrometry allowed rapid and reliable identification of the target peptides and a number of associated side products. In solid-phase synthesis of peptides and small proteins such side products are inevitable, therefore the use of CZE and/or high-performance liquid chromatography combined with mass spectrometry is gaining a central role in such synthesis procedures.