Capillary interface

Figure 9.12 Schematic diagram of the silica sheath electrospray needle used to interface capillary zone electi ophoresis with a mass spectrometer.

Pankow JR, Isabelle LM, Kristensen TJ. 1982. Tenax-GC cartridge for interfacing capillary column gas chromatography with adsorption/thermal desorption for determination of trace organics. Anal Chem 54 1815-1819. 

Sutton, K. L., and Caruso, J. A. (1999). Interfacing capillary electrophoresis with inductively coupled plasma mass spectrometry. LC-GC 17, 36—44. 

The rapid separation capability of CZE for ions in solution and its low sample volumes and flow rates mean it is excellent for speciation studies, and Dabek-Zlotorzynaska et al (1998) have written a comprehensive review of the field. Hybrid techniques with CZE are still novel and work is concentrating on perfecting the interfaces which must be able to cope with rapid separations and very low sample volumes. A helium MIP with atomic emission detection has been coupled to CZE an ion-exchange membrane capillary was used to connect the separation capillary to the interfacing capillary (Liu and Lopez Avila, 1993). CZE... 

B. Michalke, P. Schramel, Selenium speciation by interfacing capillary electrophoresis with inductively coupled plasmaDmass spectrometry, Electrophoresis, 19 (1998), 270D275. 

Tegeler, T.J., Mechref, Y., Boraas, K., Reilly, J.P and Novotny, M.V. (2004) Microdeposition device interfacing capillary electrochromatography and microcolumn liquid chromatography with matrix-assisted laser desorption/ionization mass spectrometry. Anal. Chem. 76, 6698—6706. 

The quality of the solvents used in the mobile phase is important in LC-MS. Phthalates and other solvent contaminants can cause problems [7]. Appropriate filtering of the solvents over a 0.2-0.4-pm filter is required. Degassing of the mobile phase is required to prevent air bubble formation in the pump heads, but also in interface capillaries. 

T.J. Tegeler, Y. Mechref, K. Boraas, J.P. Reilly, M.V. Novotny, Microdeposition device interfacing capillary electrochromatography and microcolumn LC with MALDI-MS, Anal. Chem., 76 (2004) 6698. 

Interfacing Capillary Electrophoresis to the Inductively Coupled Plasma-Mass Spectrometer... 

Chartogne, A. Tjaden, U.R. Van der Greef, J. A Lrcc-llow Electrophoresis Chip Device for Interfacing Capillary Isoelectric Focusing On-line with Electrospray Mass Spectrometry, Rapid Commun. Mass Spectrom. 14, 1269-1274 (2000). 

Detector MS, VG Trio 2 with a thermospray-plasmaspray LC interface, capillary probe tip at 300°... 

Applications of cze include the detection of trace amounts of DNA and the separation of peptide fragments. Furthermore, this technique is beneficial to forensic scientists because restriction mapping can be performed, allowing assays for DNA to be carried out at the scene of a crime (see Forensic testing). It is also possible to interface capillary electrophoresis on-line with a mass spectrometer as a sample introduction technique in the analysis of amino acids and proteins (70). Further improvements in capillary electrophoresis include the need to increase column capacity. Most reported separations involve the resolution of only 20—30 components, whereas high resolution hplc is capable of resolving several hundred components in a mixture (see Chromatography). 

Pankow, J. F., Isabelle, L. M., Kristensen, T. J. Tenax-GC Cartridge for Interfacing Capillary Column Gas Chromatography with Adsorption/Thermal Desorption for Determination of Trace Organics, Anal. Chem. 54, 1815 (1982)... 

While ESI and MALDI are the most commonly used ionization techniques for the MS analysis of biological samples, many other ionization mechanisms do exist and some of them were already implemented on microfluidic devices. APCI and various laser desorption ionization sources were pursued. A miniaturized APCI nebulizer chip, fabricated from silicon and Pyrex glass wafers, was designed to accommodate sample inlet capillaries, a stopper, a vaporizer channel, and a nozzle. The nebulizer chip was used to interface capillary LC to MS, but could be integrated within CE separation chips as well. 

Alternatively, a microfabricated piezo-actuated flow-through dispenser was utilized to interface capillary LC to MALDI/TOF-MS. Accurate deposition of 60-pL sample droplets to a confined area of 300 X 300 tim. and repetitive microdispensing, allowed for on-spot sample enrichment and 10-50 times signal amplification.Detection limits were 100 amol from 1 nM solution. 

Interfacing capillary columns Direct introduction of the capillary column into the ion source of the... 

Interfacing capillary columns with spectroscopic detectors (MS, FTIR, AED)... 

Fused silica introduced by Hewlett-Packard 1981-1984 Deactivation procedures and cross-linked stationary phases 1981-1988 Interfacing capillary columns with spectroscopic detectors (MS, FTIR, AED) 1983 Megabore column introduced as an alternative to the packed column... 

Detector MS, Finnigan MAT TSQ700, triple-stage quadrupole, electrospray, collision gas argon, positive ion mode, spray voltage 4 kV, sheath gas 90 psi, interface capillary 200°, collision offset - 20 V, m/z 293... 

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