Capillary electrophoretic and mass spectrometric analysis of a polydisperse fluorosurfactant

Capillary electrophoretic separation and fractionation of hydrophobic peptides onto a pre-structured matrix assisted laser desorption/ ionization target for mass spectrometric analysis

A CE separation of hydrophobic peptides followed by fractionation onto a prestructured MALDI target and off-line MS analysis was performed. An improved and partially automated manufacturing procedure of the previously described MALDI target is presented. This target is structurally coated with silicone and especially developed for hydrophobic peptides and proteins. Here, the target plate was designed specifically for the CE fraction collection. Different solvents were evaluated to meet the requirements of peptide solubility and compatibility to both the CE and MALDI methods and to the fractionation procedure. CE-MALDI-MS analysis of nine highly hydrophobic peptides from cyanogen bromide-digested bacteriorhodopsin is demonstrated.

Lack of association between a cationic protein and a cationic fluorosurfactant

Surface tension, 19F and 1H NMR spectroscopy, and cryotransmission electron microscopy are used to characterize the state of association in aqueous solutions of a fluorosurfactant CF3(CF2)nSO2NH(CH2)3-4N(CH3)3+ I- (n = 8, 6) with and without lysozyme added. In the absence of lysozyme, we find monomers, small aggregates, and large vesicles to coexist, with the individual fluorosurfactant molecules exchanging slowly (>1 ms) among those states. When both lysozyme and fluorosurfactant are present in the solution, they have no measurable influence on the physical state of the other. In contrast, a hydrogenated cationic surfactant with the same headgroup, hexadecyltrimethylammonium bromide, is shown to associate to lysozyme.

Progress in capillary electrophoresis coupled to matrix-assisted laser desorption/ionization - time of flight mass spectrometry

In this review the most important techniques developed to hyphenate CE to MALDI-TOF-MS are summarized. The principles of the different interfaces and ways to solve the hyphenation problem are explained and discussed in detail. The most important applications especially in the proteomic field are reviewed, and the advantages of CE-MALDI-TOF-MS for the analysis of these compounds compared to other techniques such as ESI-MS are exhaustingly discussed from a critical point of view. CE coupled to MALDI-TOF-MS has started to overpass traditionally used CE-coupling techniques, especially CE-ESI-MS, offering the possibility to analyze samples of interest even weeks after CE analysis and using multiplexing systems for high-sample throughput.