Mass spectrometry detectors proteomics

The detector in capillary electrophoresis is the main component in nanoanalyses. Many detectors can be used for this purpose but the mass spectrometer is the best one due to its wide ranges and low concentration detection capabilities. In the last few years, time-of-flight-mass spectrometry (TOF-MS) instruments have come onto the market and are available in many sizes, but small instruments are preferred in NCE. Bruker (Billerica, MA) has provided a micro-TOF-MS-LC (2x2x4 feet) system for nanoanalyses. Bruker also introduced a Q-q-FTMS (Fourier transform mass spectrometer) for proteomics called the APEX-QE. It offers fast, dual quadrupoles, which provides the first stages followed by FTMS for the highest mass accuracy. It can be coupled to NCE and controlled by Bmker s ProteinScape work flow and warehousing... 

Figure 9.2 The basic components of a mass spectrometer. All mass spectrometers consist of an ion source linked to a mass analyser then to a detector. The important ion sources and mass analysers for biological mass spectrometry are listed. There are many other potential ion sources and mass analysers used generally in mass spectrometry, but only the indicated are of use in the analysis of biological macromolecules and amphiphilic lipids, and also in proteomics FAB fast atom bombardment MALDI matrix-assisted laser desorption and ionization ESI electrospray ionization ToF time of flight FTICR fourier transform ion cyclotron resonance MS/MS tandem mass spectrometry.

Protein expression encompasses an enormous dynamic range. Since rare proteins cannot be amplified by any type of PCR method, sensitive detection is critical to proteome projects. Fluorescence methods deliver streamlined detection protocols, superior detection sensitivity, broad linear dynamic range and excellent compatibility with modem microchemical identification methods such as mass spectrometry. Two general approaches to fluorescence detection of proteins are the covalent derivatization of proteins with fluorophores or noncovalent interaction of fluorophores through direct electrostatic interaction with proteins. One approach for quantifying fluorescence is to use a photomultiplier tube detector combined with a laser... 

Twerenbold, D., Gerber, D., Gritti, D., Gonin, Y., Netuschill, A., Rossel, F., Schenker, D., and Vuilleumier, J. L., Single molecule detector for mass spectrometry with mass independent detection efficiency, Proteomics, 1, 66-69, 2001. 

In recent years, mass spectrometry has become one of the key technologies in proteome and genome research because of the rapid development of new components — from the ion sources to the detector — and intergration into the World Wide Web has also helped to make this possible. 

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