Simulation and optimization of peptide separation by capillary electrophoresis-mass spectrometry

Abstract

The potential of capillary electrophoresis (CE) for the separation of peptides has been extensively demonstrated in the last decade. Their correct characterization and sequenciation is a difficult task that can be accomplished using CE-mass spectrometry (CE-MS). An important limitation of CE-MS is the buffer choice since it should provide an adequate CE separation without ruining the MS signal. In this work, a new strategy is used to help to solve this limitation based on the combination of two different methodologies. Namely, an ab initio semiempirical model that relates electrophoretic behavior of peptides to their sequence is first used to obtain in a fast and easy way adequate CE buffers compatible with MS analysis. Next, CE-MS is used to separate and characterize peptides via the determination of their relative molecular masses. The usefulness of this procedure is demonstrated analyzing in a single CE-MS run a group of 10 standard peptides of very different nature (i.e., relative molecular masses ranging from 132 to 1037 and isoelectric points ranging from 5.69 to 10.62). It is concluded that the use of this strategy can help to overcome the buffer limitation in CE-MS.

Capillary electrophoresis – mass spectrometry: 15 years of developments and applications

“…Magnetic sector Sheathless [164] Sequence analysis of peptides MPC-CZE Magnetic sector Sheath liquid [165] Peptide standards SPE-CZE Ion trap Sheathless [166] Proteins and proteomes SPE-CZE Sheathless [167] Proteolytic digests CZE Triple quadrupole, QqTOF Sheath liquid [168] Neurotransmitters and neuropeptides CZE Triple quadrupole Sheath liquid [169] Metallothioneins CZE Triple quadrupole Sheathless [170] Protein standards CZE Single quadrupole Sheath liquid [171] Analysis of proteins from SDS-PAGE gels CZE IT-reTOF-MS Sheathless [172] Neuropeptide Y, its fragments and two of their degradation products CZE Sheath liquid [173] Proteins in complexes, proteolytic digests CZE/micro-SPE Ion trap Liquid junction [174] Phosphopeptides IMAC-CZE c) Ion trap In-column electrode [175] Reduced and oxidized forms of cytochrome c [176] Phospholipase glycosylation patterns of bee venoms CD-CZE Ion trap Sheath liquid, sheathless [177] Gel-isolated membrane proteins CZE Triple quadrupole, QqTOF Sheathless [178] Peptide standards CZE TOF Sheathless [179] 20 natural amino acids in children's blood CZE Tandem quadrupole Sheath liquid [180] Evaluation of immobilized trypsin beds for on-line digestion of proteins CZE Single quadrupole Sheathless [181] Protein profiles of Siberian permafrost bacteria CZE IT-reTOF [182] Phosphorylation sites of proteins IMAC-CZE Ion trap [183] Protein standards TITP Single quadrupole Sheath liquid [183] Cytochrome c digests and a peptidomimetic direct thrombin inhibitor TITP Single quadrupole Sheath liquid [184] Bacterial proteomes CIEF FTICR Sheath liquid [185] Histones CZE Sheath liquid [186] Metal displacement of a mouse liver metallothionein CZE Triple quadrupole Sheath liquid [187] Protein standards in PEG-containing samples CZE Triple quadrupole Sheath liquid [188] Amyloid-b peptide CZE Single quadrupole Sheath liquid [189] Protein standards CZE Ion trap Sheath liquid [190] Peptide standards CZE Ion trap Sheath liquid …”

Capillary electrophoresis‐mass spectrometry: Recent advances to the analysis of small achiral and chiral solutes

“…The potential of CZE-MS has been successfully applied for the analysis of amino acids and peptides in the last decade. An ab initio model that generates a simulated electropherogram for the prediction of peptide migration in CE was used to optimize a migration pattern of ten peptides [48]. Since the method development of CE-ESI-MS for peptide separation is very time-consuming (due to the optimization of different pH and buffer concentrations), the simulated electropherograms can be used to reduce the number of experiments during separation optimization.…”

Recent advances in the application of capillary electromigration methods for food analysis

“…Two novel procedures aimed at determining the amino acid sequence of peptides of interest for the food industry have recently been published. Thus, Simó et al [41] combined the use of a theoretical model that correlates electrophoretic behavior of peptides to their sequence together with CE-MS [44,45] for the study of the cleavage activity of a recombinant pepsin versus its corresponding natural variety using cytochrome C (CytC) as a substrate. To do this, hydrolysates were first analyzed by CE coupled to electrospray ionization mass spectrometry (ESI-MS).…”