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Published byLaurel Harrington Modified over 9 years ago
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Dr. Kristoffer Rem Labing-isa Massachusetts Institute of Technology Dean, College of Science
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Early called as ‘spectrograph’ Spectrograph had became part of the International Scientific Vocabulary *International Scientific Vocabulary comprises scientific and specialized words whose language of origin may or may not be certain, but which are in current use in several modern languages.
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Spectrograph, ‘spectr’ from spectrum and ‘ograph’ from photograph Spectrograph records a spectrum on a photographic plate Mass spectroscopy is discouraged due to confusion with ‘light spectroscopy’
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Mass-Spec or MS Analytical technique that measures the mass to charge ratio of charged particle Used for determining masses of particles, elemental composition, and elucidating the chemical structures
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Eugen Goldstein observed rays in gas discharges under low pressure that travels from anode to cathode He named it ‘kanalstrahlen’ or the canal rays, an anode ray
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Wilhelm Wien found that strong magnetic fields deflect the canal rays J. J. Thomson later improved the work of Wien. First application of mass spec is on the amino acids and peptide
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Converts gas phase sample molecules into ions. Ion Source *In electrospray ionization, ions that exist in solution is converted into gas phase
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Sorts or organizes the ions according to their masses. Mass Analyzer
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Measures the value of an indicator quantity, thus provides data for calculating the abundances of each ion present Detector
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A sample is loaded onto the MS instrument and undergoes vaporization First Step
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Components of the sample are ionized by one of a variety of methods such as impacting them with an electron beam Second Step
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Ions are separated according to their mass-to-charge ratio in an analyzer by electromagnetic fields Third Step
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Ions are detected, usually by a quantitative method Fourth Step
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The ion signal is processed into mass spectra Fifth Step
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A sample is loaded onto the MS instrument and undergoes vaporization
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The analyte is ionized by chemical ion-molecule reactions during collisions in the source Chemical Ionization
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Ions are separated according to their mass-to-charge ratio in an analyzer by electromagnetic fields
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Mass analyzers separate the ions according to their mass-to-charge ratio. F = ma
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The analyte is ionized by chemical ion-molecule reactions during collisions in the source Chemical Ionization
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A sample of sodium chloride Vaporized NaCl Ionized NaCl Na23 Cl35 Cl37 Na23
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Cl35 Cl37 Na23 Cl35 Cl37 Na23
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Cl35 Cl37 Lighter ions get deflected by the magnetic force more than heavier ions
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