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Mini 12 can perform MS 5 and analyze directly such complex samples as whole blood, untreated food, and environmental samples, without sample preparation or chromatographic separation. [17] Miniature mass spectrometer systems. 1st Detect introduced the MMS 1000 which is a cylindrical ion-trap mass spectrometer with MS/MS capability. Some ...
Theoretical isotope distribution for the molecular ion of caffeine. The molecular mass (abbreviated M r) of a substance, formerly also called molecular weight and abbreviated as MW, is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of 12 C).
A common combination is gas chromatography-mass spectrometry (GC/MS or GC-MS). In this technique, a gas chromatograph is used to separate different compounds. This stream of separated compounds is fed online into the ion source, a metallic filament to which voltage is applied. This filament emits electrons which ionize the compounds.
A mass-selecting quadrupole and collision quadrupole with time-of-flight device as the second mass selection stage is a hybrid known as a quadrupole time-of-flight mass spectrometer (QTOF MS). [ 8 ] [ 9 ] Quadrupole-quadrupole-time-of-flight (QqTOF) configurations are also possible and used especially the mass spectrometry of peptides and other ...
Electron-transfer dissociation (ETD) is a method of fragmenting multiply-charged gaseous macromolecules in a mass spectrometer between the stages of tandem mass spectrometry (MS/MS). [1] Similar to electron-capture dissociation , ETD induces fragmentation of large, multiply-charged cations by transferring electrons to them. [ 2 ]
A typical workflow of a peptide mass fingerprinting experiment. Peptide mass fingerprinting (PMF), also known as protein fingerprinting, is an analytical technique for protein identification in which the unknown protein of interest is first cleaved into smaller peptides, whose absolute masses can be accurately measured with a mass spectrometer such as MALDI-TOF or ESI-TOF. [1]
LibreOffice Calc is the spreadsheet component of the LibreOffice software package. [5] [6]After forking from OpenOffice.org in 2010, LibreOffice Calc underwent a massive re-work of external reference handling to fix many defects in formula calculations involving external references, and to boost data caching performance, especially when referencing large data ranges.
Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...