Gas Chromatography (GC) (IUPAC Compendium of Chemical Terminology):
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Lecture 3. <strong>Gas</strong> chromathography.<br />
Columns.<br />
Open tubular (capillary) columns.<br />
Typical length is 15 to 100 m. Inner diameter is 0.10 to 0.53 mm. Narrow columns<br />
provide higher resolution but require higher operation pressure and have less<br />
sample capacity.<br />
WCOT (wall-coated open tubular) columns.<br />
Column wall<br />
Stationary<br />
liquid phase<br />
This type <strong>of</strong> columns features a 0.1 to 5 μm thick film <strong>of</strong> stationary liquid phase on<br />
inner wall <strong>of</strong> the column. Decreasing the thickness <strong>of</strong> the stationary phase increases<br />
resolution, decrease retention time, and decrease sample capacity. Most capillary<br />
columns are made <strong>of</strong> fused-silica with a polyimide outer coating. These columns are<br />
flexible, so a very long column can be wound into a small coil.<br />
SCOT (support-coated open tubular) columns.<br />
Column wall<br />
Solid support<br />
coated with<br />
stationary<br />
liquid phase<br />
This type <strong>of</strong> columns has solid particles coated with stationary liquid phase and<br />
attached to the inner wall.<br />
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