Capillary electrophoresis using a surfactant-treated capillary coupled with offline matrix-assisted laser desorption ionization mass spectrometry for high efficiency and sensitivity detection of proteins.

摘要: Abstract A method of combining capillary electrophoresis (CE) using a surfactant-modified with matrix-assisted laser desorption ionization (MALDI) mass spectrometry (MS) is described for protein analysis. The CE–MALDI-MS coupling based on CE fraction collection nanoliter volume samples in less than 5 μl dilute acid. This offline does not require any special instrumentation and can be readily performed commercial instruments. Protein adsorption during separation prevented by coating the surfactant didodecyldimethylammonium bromide. binds strongly wall, hence it desorb significantly to interfere subsequent MALDI-MS It shown that use acid advantageous lowering detection limit compared an electrophoretic buffer. proteins such as cytochrome c 23 fmol injected CE, or 1.2 spotted MALDI-MS. sensitivity comparable alternative techniques direct sample deposition MALDI target. In addition, approach has advantage allowing multiple reactions carried out fractioned sample. These are very important identification structure