Understanding the Significance of Capillary Columns

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Understanding the Significance of Capillary
Columns
Due to advancements made in the later part of
19th century we can truly say that gas
chromatography is a mature technique now. If we
take into consideration the installed instruments
throughout the world the gas chromatography
instruments still is far ahead of high
performance liquid chromatography instruments.
When you setup a gas chromatogram you will
purchase accessories, gases and columns with it
and column is the most crucial part of the whole
purchase if considers each part individually.
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Thus it is often repeated phrase in the lab
fraternity that Column is the heart of the
chromatograph.  More than 80 of the gas
chromatograms use capillary columns nowadays. In
present times open- tubular columns as in demand,
in this an inert tube of long length is column.
In this the free flow of gas is ensured as the
center of the tube is open sans any packaging
material. Chemical bonding of the stationary
phase id done on the inner walls of the tube and
is how coating is done. Capillary columns have
become such a sought after tools because of
ability to bond and cross link the stationary
phase. If we want to increase the efficiency of
capillary column we just have to replace the
capillary column which uses non- cross linked
phase and non bonded phase with bonded and
cross linked phase.
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Now to understand the make of the capillary
columns, fused silica, borosilicate glass and
stainless steel are the main components. The
internal diameter is few tenths of a millimeter.
The length can go beyond 10 meters till 60
meters. If the walls if the capillary tubes are
coated with a liquid stationary phase, the
columns are known as wall coated open tubular
(WCOT). Another type is where the inner wall is
lines with a support material which is usually
thin layered on which stationary phase is
adsorbed. An example of this support material is
diatomaceous earth. These are popularly known as
support coated open tubular (SCOT) capillary
columns. If we compare the efficiency WCOT are
far superior to SCOT capillary columns.
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This is the result of higher separation
capability of the WCOT columns. The most recent
advancement is fused silica open tubular (FSOT)
column. It has even thinner walls as compared to
glass capillary column. The source of strength is
polyamide coating. Other positive features which
separate it from other type of capillary columns
is low reactivity, high physical strength and
flexibility. Liquid chromatography Mass
spectrometry (LC-MS) is now routinely used as
electrospray ionization (ESI) has been developed
which has provided a robust and simple
interface.  In biochemistry and other branched of
sciences the MS technology along with immunoassay
has paved way for better and more economical
laboratories. It is a highly chemical
identification technique. 
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To effectively and totally remove solvent of a
sample to stop it from going through from the
source of ions to the detector and the
quadrupole. If we will not remove the solvent the
results will not be good and the sensitivity of
instrument will be drastically reduced. It is
better to get an on-site LC/MS nitrogen
generator as it is more economical as compared to
purchase of nitrogen for experimentation. Quadrex
is one of the premium LC/MC nitrogen generator
manufacturing companies that is known for its
finesse and class.
SOURCE
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the-significance-of-capillary-columns