Nano ESI

Volume Gas phase, LVI, LV HSI, LVS, PLC Liquid/solid phase, CIS, CT, SPME, nano-ESI... 

Applied Biosystems Q q TOF analyser equipped with a nanoelectrospray ion source for nano ESI MS and nano ESI MS/ MS analysis... 

Y. An, J. W. Cooper, B. M. Balgley, and C. S. Lee. Selective Enrichment and Ultrasensitive Identification of Trace Peptides in Proteome Analysis Using Transient Capillary Isotachophoresis/Zone Electrophoresis Coupled with Nano-ESI-MS. Electrophoresis, 27(2006) 3599-3608. 

Mirabaud, S., Rolando, C. and Regert, M. (2007). Molecular criteria for discriminating adipose fat and milk from different species by nano ESI MS and MS/MS of their triacylglycerols application to archaeological remains. Analytical Chemistry 79 6182-6192. 

Karas, M. Bahr, U. Dtilcks, T. Nano-ESI-MS Addressing Analytical Problems Beyond Routine. Fresenius J. Anal. Chem. 2001, 366,669-676. 

Furthermore, if the affinity is to be measured in water, then ESI must be done with solutions that have high contents of water, which is difficult or impossible. Another problem is that different source configurations (e.g. normal vs nano ESI), desolvation conditions, and instruments may give different results in affinity determinations [95]. 

In 1974, Comarisov and Marshall60 developed Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). This technique allows mass spectrometric measurements at ultrahigh mass resolution (R = 100000-1000000), which is higher than that of any other type of mass spectrometer and has the highest mass accuracy at attomole detection limits. FTICR-MS is applied today together with soft ionization techniques, such as nano ESI (electrospray ionization) or MALDI (matrix assisted laser/desorption ionization) sources. 

Schmidt, A., Karas, M., and Dulcks, T. (2003). Effect of different solution flow rates on analyte ion signals in nano-ESI MS, or when does ESI turn into nano-ESI J. Am. Soc. Mass Spectrom. 14 492-500. 

For nano-ESI-MS MS , the sample is loaded either in a previously rinsed gold/palladium-coated nanospray capillary (Promega) or in a PicoTip emitter (New Objective) and analyzed in a nanospray source. 

The online or offline LC-ESI analysis also generated a list of peptide masses which were usually complementary to the MALDI peaklist. The few microliters left from the collected fractions after MALDI-MS analysis can be used, when necessary, for complementary analysis (MALDI-MS-MS or nano-ESI-MSn). 

The dynamic development of mass spectrometry has had a huge impact on lipid analysis. Currently, a variety of suitable mass spectrometers is available. In principal, a mass spectrometer consists of an ion source, a mass analyzer, and an ion detector. The typical features of each instrument (Fig. 2) result mostly from the types of ion source and mass analyzer. To date, the ionization techniques apphed to lipid analysis include Electrospray Ionization (ESI or nano-ESI), Atmospheric Pressure Chemical Ionization (APCI), Matrix-Assisted Laser Desorption/Ionization... 

MALDI), and, more recently, Atmospheric Pressure Photo Ionization (APPI) and Desorption Electrospray Ionization (DESI). For the majority of analytical tasks in hpidomics, ESI and nano-ESI are the most common choices. 

Farwanah H, Pierstorff B, Schmelzer CEH, Raith K, Neu-bert RHH, Kolter T, Sandhoff K. Separation and mass spec-trometric characterization of covalently bound skin ceramides using LC/APCI-MS and nano-ESI-MS/MS. J. Chromatogr. B. 2007 852 562-570. 

A. Shevchenko, 1. Chemushevich, W. Ens, K.G. Standing, B. Thomson, M. Wilm, M. Maim, Rapid de novo peptide sequencing by a combination of nano-ESI, isotopic labeling and a Q-TOF-MS,RjapiAComnam. Mass Spectrom., 11 (1997) 1015. 

The specific design of the various sample introduction devices or spray probes depends to a large extent on the technique applied, i.e., ESI, APCI, or other. With respect to ESI, systems have been described for conventional pure ESI, pneumatically-assisted ESI or ionspray, ultrasonically-assisted ESI, thermally-assisted ESI, and micro- and nano-ESI (Ch. 5.5). The heated-nebulizer system (Ch. 5.6.2) is used in APCI and atmospheric-pressure photoionization (APPI). 

Vanhoutte et al. [81] compared various nano-ESI tips. With the uncoated non-tapered 20-pm-lD fused-silica tips, delivered with the Mcromass NanoFlow probe, the sensitivity was dependent of the mobile-phase compositiom Replacing these tips by uncoated tapered ones (20 9 pm ID) showed some improvement, while the best results, especially at low percentages of methanol in the mobile phase, were achieved with gold-coated tapered fused-silica tips. 

Nano-ESI devices and needles are commercially available from Proxeon Biosystems (formerly Protana, Odense, Danmark), New Objective Inc. (Cambridge, MA), and NanoSeparations (Nieuwkoop, the Netherlands). Nano-ESI devices are also available from the instrument manufacturers. 

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