Nano liquid chromatography-electrospray

Ficarro, S. B., Salomon, A. R., BriU, L. M., Mason, D. E., Stettler-GiU, M., Brock, A., and Peters, E. C., Automated immobilized metal affinity chromatography/nano-liquid chromatography/electrospray ionization mass spectrometry platform for profiling protein phosphorylation sites, Rapid Communications in Mass Spectrometry 19(1), 57-71, 2005. 

Reverse-phase columns with a gradient elution in combination with UV-Vis spectrophotometers using photodiode-array (PDA) (Fig. 1.6) and spectrofiuorimeters are common devices employed in this technique. In a lesser extent, MS, tandem mass spectrometry (MS-MS), and nano liquid chromatography-electrospray ionization-quadrupole time-of-flight tandem mass spectrometry (nanoLC-nanoESI-Q-qTOF-MS-MS) has been used as detection system. This instrumentation has been mainly used in the analysis of dyes and proteinaceous media, and in some extent, in the analysis of drying oils and terpenoid varnishes [47,48],... 

This protocol describes a procedure for the identification of PTM by HNE to reveal protein targets and specific sites of covalent attachment. Identification is performed by combining proteolytic digestion followed by SPH enrichment and nanoscale liquid chromatography-electrospray ionization tandem mass spectrometry (nano-LC-ESI-MS/MS).The modified proteins are subjected to reduction, alkylation, and subsequent digestion by a proteolytic enzyme. The peptides thus obtained are desalted and the substoichiometric quantities of HNE-modified peptides are fractionated from unmodified species using hydrazide-coated glass beads-based enrichment technique that selectively captures peptide carbonyls (as hydrazones) that are subsequently... 

Bile acids, alcohols, and side-chain-shortened steroids have been extensively analyzed by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) [1-3].The mobile phase usually features water/ methanol or water/acetonitrile containing an organic acid or buffer. As ESI is a concentration-dependent process, maximum sensitivity is obtained with high-concentration, low-volume samples run at low flow rate [26,27]. We have extensively used low-flow-rate LC-ESI-MS to achieve maximum sensitivity for steroid analysis [26], and with the advent of reliable nanoscale liquid chromatography (nano-LC) equipment, this form... 

Alexander, J. N., Schultz, G. A., and Polll, J. B. (1998). Development of a nano-electrospray mass spectrometry source for nanoscale liquid chromatography and sheathless capillary electrophoresis. Rapid Commun. Mass Spectrom. 12, 1187—1191. 

Recently, the word nano has become a trend in science and technology and some of us think that it is the new generation but, as mentioned above, its root is about 22 years old. NLC and NCE are gaining importance day by day. They are very useful and effective tools for samples of low quantities or having low concentrations of the analytes. Columns of low internal diameter are ideal for use in NLC and NCE, especially with detectors requiring very low flow rates, such as electrospray liquid chromatography/mass spectroscopy (LC/MS). Besides, these columns offer high sensitivity due to their low... 

As a rule, a separation method should be used for both purification and concentration of the sample. The classic method for peptides and proteins is a reverse-phase liquid chromatography preparation of the sample, followed by a concentration step (often lyophiliza-tion) of the fraction of interest. During those steps performed on very small quantities of sample, loss on the sample can occur if care is not taken to avoid it. Lyophilization, for instance, can lead to the loss of the sample absorbed on the walls of the vial. The use of separation methods on-line with the mass spectrometer often are preferred. Micro- or nano-HPLC [32,33] and capillary electrophoresis [34], both coupled mainly to electrospray ionization/mass spectrometry (ESI-MS), are used more and more. 

Creaser, C.S., Lill, J.R., Bonner, P.L., Hill, S.C., and Rees, R.C., 2000, Nano-electrospray and microbore liquid chromatography-ion trap mass spectrometry studies of copper complexation with MHC restricted peptides. Analyst 125 599-603. 

Budimir N, Weston DJ, Creaser CS et al. (2007) Analysis of pharmaceutical formulations using atmospheric pressure ion mobdity spectrometry combined with liquid chromatography and nano-electrospray ionization. Analyst. 132 34-40. 

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