Capillary liquid chromatography automation

Belov ME, Anderson GA, Wingerd MA, et al. An automated high performance capillary liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometer for high-throughput proteomics. J Am Soc Mass Spectrom 2004 15(2) 212-232. 

Figure 9.6 Surfer-generated chromatoeletropherogram of fluorescamine-labeled tryptic digest of ovalbumin. Reprinted from Analytical Chemistry, 62, M. M. Bushey and J. W. Jorgenson, Automated instrumentation for comprehensive two-dimensional high-performance liquid chromatography/capillary zone electrophoresis, pp 978-984, copyright 1990, with permission from the American Chemical Society.

Alexander IV, J.N., Poli J.B., and Markides K.E., Evaluation of automated isocratic and gradient nano-liquid chromatography and capillary electrochromatography, Anal. Chem. 71, 2398, 1999. 

The most important features of liquid membranes are that they olfer highly selective extraction, efficient enrichment of analytes from the matrix in only one step, and the possibility of automated interfacing to different analytical instruments such as liquid chromatography, gas chromatography, capillary zone electrophoresis, UV spectrophotometry, atomic absorption spectrometry, and mass spectrometry [82]. 

This area of analytical chemistry includes a great number of instruments that range from colour comparators and other visual comparison devices to automated spectrophotometers that can carry out multicomponent analysis. Liquid chromatography and capillary electrophoresis have accelerated the development of improved UV/Visible detectors, which are at the origin of the current mode of acquiring chromatograms, accompanied by the possibility of identification and quantification of compounds. 

Alternatives to two-dimensional electrophoresis are currently under development in these approaches, liquid chromatography or capillary electrophoresis is used for easier automation and capability of high-throughput application. 

I. L. Davies, M. Raynor, P. T. Williams, G. E. Andrews and K. D. Bartle, Application of an automated on-hne microbore high-performance liquid chromatography/capillary gas chromatography to diesel exhaust particulates , Anal. Chem. 59 2579-2583 (1987). 

Sensors for the detection of enantiomers are of great interest, as so far the on-line monitoring of production processes and medical diagnostics using standard chemical analytical methods is not possible. Quite often only one enantiomer of a chiral compound is actually a bioactive therapeutic. Therefore a proper analysis of the final product is essential. Currently, this involves separation techniques like liquid chromatography, GC and capillary electrophoresis, and determination of enantiomeric purity with circular dichro-ism and specific rotation. These are all off-line procedures and therefore no real-time analysis can be performed. Sensing devices for the distinction of different enantiomers would be a much cheaper, faster and easier-to-use alternative for this task, amenable to automation. 

Stevenson, T. I. Loo, J. A. Greis, K. D. 1998. Coupling capillary high-performance liquid chromatography to matrix-assisted laser desorption/ionization mass spectrometry and N-terminal sequencing of peptides via automated microblotting onto membrane substrates. Anal. Biochem., 262,99-109. 

As an instrumental approach to conventional electrophoresis, capillary electrophoresis offers the capability of on-line detection, micropreparative operation and automation (6,8,45-47). In addition, the in tandem connection of capillary electrophoresis to other spectroscopy techniques, such as mass spectrometry, provides high information content on many components of the simple or complex peptide under study. For example, it has been possible to separate and characterize various dynorphins by capillary electrophoresis-mass spectrometry (33). Therefore, the combination of CE-mass spectrometry (CE-MS) provides a valuable analytical tool useful for the fast identification and structural characterization of peptides. Recently, it has been demonstrated that the use of atmospheric pressure ionization using Ion Spray Liquid Chromatography/ Mass Spectrometry is well suited for CE/MS (48). This approach to CE/MS provides a very effective and straightforward method which allow the feasibility of obtaining CE/MS data for peptides from actual biological extracts, i.e., analysis of neuropeptides from equine cerebral spinal fluid (33). 

Automated methods frequently exhibit remarkable performance not only in terms of sample throughput and cost, but in relation to the quality of results, especially in relation to repeatability and reproducibility. Several systems are currently available that enable simple automation of manual gestures these include automatic titra-tors, pH-meters with a circulating cell, etc., and involve approaches that are not fundamentally different to the corresponding manual method. These techniques are not, however, described in this chapter, nor are gas and liquid chromatography and capillary electrophoresis, automated techniques, that may be present but are not routinely used in oenological laboratories. 

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