| LINEAR: The LC
method is said to be LINEAR when plots of peak-size
versus sample concentration are straight lines. In
practice, it is also desirable to have the plot pass
through the origin.
|
 The calibration plot is a graphical representation of the relationship between peak size and amount of analyte injected.
|
|
| LINEARITY
CHECK: The measurement of peak size in an
LC assay for a series of samples of different
concentration. The LC method is said to be LINEAR when
plots of peak size versus sample concentration are
straight lines and pass through the origin.
|
||
| LIQUID CHROMATOGRAPH: the instrument or equipment used
to perform an HPLC separation.
|
Agilent 1100 HPLC System
|
|
| LIQUID
CHROMATOGRAPHY (LC): a special kind of chromatography
where separation takes place using a liquid or solvent
that passes through a column. "LC" and "HPLC" are used interchangeably.
|
||
| LIQUID-SOLID
CHROMATOGRAPHY (LSC): another HPLC method, different
from reversed-phase chromatography. It uses mobile phases
that do not contain water. It is almost always classified
as a type of NORMAL-PHASE CHROMATOGRAPHY. Also called ADSORPTION CHROMATOGRAPHY.
|
||
| LITER (L): a unit of
volume, equal to about a quart. See Section 4B for the relationship to other
volume units.
|
||
| LOOP: a piece of tubing in a sample injector that holds the sample to be
injected and determines its volume.
|
Cross-sectional diagram of a generic injector.
|
|
| LOT NUMBER:
usually refers to columns prepared from the same batch of
column packing, which therefore have the same separation
properties and give the same retention times for bands in
a given sample. Sometimes called BATCH NUMBER. Also
refers to LC solvents bottled from the same manufacturing
batch.
|
||
| LOW-PRESSURE MIXING:
a pumping procedure that mixes two or more solvents
before the pump to form a mobile phase then delivers the
mixture to the LC system. A single pump plus a controller
are used, so such systems are often referred to as "one
pump" systems.
See also HIGH PRESSURE MIXING.
|
Thermo Separations Products one-pump gradient HPLC System
|
|
