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Team:Bielefeld-Germany/Project/Background/Technology
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Matrix-assisted Laser Desorption/Ionization – Time of flight (MALDI-TOF) is a procedure to analyze large biomolecules by their mass. | Matrix-assisted Laser Desorption/Ionization – Time of flight (MALDI-TOF) is a procedure to analyze large biomolecules by their mass. | ||
Before measuring, the analyte is cocristalized on an metal plate within a solid matrix, 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid) and 2,5-dihydroxybenzoic acid (DHB) are most commonly used. | Before measuring, the analyte is cocristalized on an metal plate within a solid matrix, 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid) and 2,5-dihydroxybenzoic acid (DHB) are most commonly used. | ||
| + | Desorption of the analyte is taken by a laser beam, commonly with a wavelength of 337 nm. The matrix absorbs the laser light and the upper layer explosively vaporizes, ejecting both, matrix and analyte molecules. In addition to this vaporization, the laser beam also leads to an ionization of the analytes. The mass analysis is taken by the TOF (Time of flight)-Analysator. The evaporated ions are accelerated by an electric field. Typical acceleration voltages for this are 10-30 kV. The velocity of an ion depends on his mass and the charge (formula). An ion detector converts the incoming ions into an electrical signal. The advantage of this method is the rapid analysis of a relatively large mass range. | ||
Revision as of 14:08, 20 September 2011
MALDI-TOF
Matrix-assisted Laser Desorption/Ionization – Time of flight (MALDI-TOF) is a procedure to analyze large biomolecules by their mass. Before measuring, the analyte is cocristalized on an metal plate within a solid matrix, 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid) and 2,5-dihydroxybenzoic acid (DHB) are most commonly used. Desorption of the analyte is taken by a laser beam, commonly with a wavelength of 337 nm. The matrix absorbs the laser light and the upper layer explosively vaporizes, ejecting both, matrix and analyte molecules. In addition to this vaporization, the laser beam also leads to an ionization of the analytes. The mass analysis is taken by the TOF (Time of flight)-Analysator. The evaporated ions are accelerated by an electric field. Typical acceleration voltages for this are 10-30 kV. The velocity of an ion depends on his mass and the charge (formula). An ion detector converts the incoming ions into an electrical signal. The advantage of this method is the rapid analysis of a relatively large mass range.
