Interactions between sodium dodecyl sulfate micelles and peptides during matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of proteolytic digests

摘要: Although sodium dodecyl sulfate (SDS) is routinely used as a denaturing agent for proteins, its presence highly detrimental on the analysis of peptides and proteins by mass spectrometry. It has been found, however, that when SDS present in concentrations near to or above critical micelle concentration (CMC), improvements matrix-assisted laser desorption/ionization spectrometry (MALDI-MS) peptide mixtures hydrophobic are obtained. To elucidate possible explanations such improvements, here we have undertaken study examining effect micelles mixtures. Fluorescently labeled were probes determine whether hydrophilic interact exclusively with micelles. In addition, four globular digested trypsin then various amounts added before MALDI examine role mixture complexity spectral results, tryptic digest bovine serum albumin was also fractionated according hydrophobicity treatment. Results from these experiments suggest micelle-peptide interactions increase peptide-matrix cocrystallization irrespective analyte hydrophobicity. As studies performed using dried-droplet method sample spotting, hypothesized reduce Marangoni effects during crystallization process.