几百个关于LCMS专用名词解释

仪器资料 · 发表于 2017-11-10 09:30:05

几百个关于LCMS专用名词解释

Base peak The most intense ion in a mass spectrum. The intensity of other ions
in the spectrum are reported as a percentage of the intensity of the base peak.
Biotransformation An alternative term for drug metabolism.
Buffer An electrolyte added to the HPLC mobile phase.
Capacity factor The parameter used in HPLC to measure the retention of
an analyte.
Capillary column This term refers to a chromatographic column of ‘small’
diameter and is used in both gas and high performance liquid chromatography.
In HPLC, the term is usually applied to columns with internal diameters
of between 0.1 and 2 mm. The term microbore column is often used synonymously
to describe these columns but is more correctly applied to columns
with internal diameters of 1 or 2 mm.
Charge-residue mechanism One of the two mechanisms used to account for
the production of ions by electrospray ionization.
Chemical ionization An ionization method used to maximize the production
of intact molecular species. Used for volatile, thermally stable analytes.
Chemical noise Signals from species other than the analyte present in the system
or sample that cannot be resolved from that of the analyte.
Chromatographic selectivity The degree to which compounds are separated
on a particular chromatographic system.
Chromatography General term for a number of methods used to separate the
individual components of a mixture.
Collision energy The energy of the collision between an ion and a gas molecule
which may be used to vary the amount of fragmentation observed.
Collision-induced dissociation Fragmentation of an ion by collision with a
gas molecule.
Concentration-sensitive detector A detector for which the intensity of response
is proportional to the concentration of analyte reaching it.
Cone-voltage fragmentation Fragmentation of ions, commonly produced by
APCI or electrospray ionization, effected by the application of a voltage within
the source of the mass spectrometer.
Constant-neutral-loss scan An MS–MS scan in which ions containing a particular
structural feature may be identified.
Corona discharge Occurs when the field at the tip of the electrode is sufficiently
high to ionize the gas surrounding it but insufficiently high to cause a
spark. An integral part of the APCI interface.
Coulombic explosion The process by which a droplet disintegrates into a
number of smaller droplets which occurs when the repulsive forces between
charges on the surface of a droplet are greater than the cohesive force of
surface tension.