What is the stationary phase of GC column?
Columns/stationary phases are considered the “heart” or “brain” of the chro- matograph and are responsible for the separation process. In the GC system, a sample is vaporized and injected into the head of the separation column packed with a finely divided solid or coated with a film of a liquid.
What is DB in GC column?
DB-1 Columns Agilent J&W DB-1 is nonpolar and low-bleed, and operates under high temperature limits. It is an excellent choice for general purpose use in a wide variety of applications. Precision-engineered DB-1 is bonded, crosslinked and solvent rinsable, and is equivalent to USP phase G2.
What is DB 5 column?
DB-5 Columns Agilent J&W DB-5 is nonpolar and low bleed, and is available in a range of column dimensions. DB-5 is also bonded, crosslinked, and solvent-rinsable, and has a high temperature limit. It is equivalent to USP phase G27.
What is DB 624 GC column?
Agilent J&W DB-624 is recommended for EPA methods 502.2 and 8021, as well as for fast GC/MS volatiles analysis. It is specifically designed for the analysis of volatile priority pollutants and residual solvents.
What is the stationary phase?
Stationary phase, in analytical chemistry, the phase over which the mobile phase passes in the technique of chromatography. Typically, the stationary phase is a porous solid (e.g., glass, silica, or alumina) that is packed into a glass or metal tube or that constitutes the walls of an open-tube capillary.
Why are GC columns long?
Due to the small pressure drop associated with open tube capillary columns, long columns of up to 60 m can easily be used. However, packed columns are tightly filled with solid support and suffer from greater pressure drops; thus, it is impossible to use packed columns much longer than 2 m .
What is a db1 column?
DB-1ms Columns Agilent J&W DB-1ms is a nonpolar, low-bleed column, with an extended upper temperature limit and excellent inertness for acids and bases. Bonded and crosslinked, this highly inert column provides maximum response for active analytes commonly found in drug screening and environmental analyses.
What is the principle of GC?
Principle of gas chromatography: The sample solution injected into the instrument enters a gas stream which transports the sample into a separation tube known as the “column.” (Helium or nitrogen is used as the so-called carrier gas.) The various components are separated inside the column.
Which column is used in GC?
Two types of columns are used in gas chromatography: packed columns and capillary columns. Short, thick columns made of glass or stainless steel tubes, packed columns have been used since the early stages of gas chromatography.
What is film thickness in GC column?
Film thickness in capillary columns, is in general between 0.1 and 10 μm for liquid stationary phases such as Rtx-1, 17 and wax. If the phase is not distributed as a film anywhere in the column, the efficiency of the column will be compromised, especially with liquid stationary phases.
How do I choose the right GC column?
The selection of the proper capillary column for any application should be based on four significant factors: stationary phase, column I.D., film thickness, and column length. The practical effects of these factors on the performance of the column are discussed briefly in this section, in order of importance.
What is stationary phase give example?
Typically, the stationary phase is a porous solid (e.g., glass, silica, or alumina) that is packed into a glass or metal tube or that constitutes the walls of an open-tube capillary. The mobile phase flows through the packed bed or column.