Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
  • G01N30/02—Column chromatography
  • G01N30/60—Construction of the column
  • G01N30/6052—Construction of the column body
  • G01N30/6069—Construction of the column body with compartments or bed substructure
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
  • G01N30/02—Column chromatography
  • G01N30/60—Construction of the column
  • G01N30/6052—Construction of the column body
  • G01N30/6073—Construction of the column body in open tubular form
  • G01N30/6078—Capillaries
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
  • G01N30/02—Column chromatography
  • G01N30/60—Construction of the column
  • G01N30/6052—Construction of the column body
  • G01N30/6082—Construction of the column body transparent to radiation

Definitions

• the present invention relates to an improved capillary column for gas chromatography.
• GC Gas chromatography
• Traditional gas chromatography is also known to be used for analysis and separation (total or partial) of a mixture of components flowing within an inert carrier gas (generally helium, hydrogen or nitrogen), via a chromatography column containing a stationary phase.
• an inert carrier gas generally helium, hydrogen or nitrogen
• the instrument used for gas chromatography consists of a gas chromatograph, the main components of which are the sample introduction system, the heated chamber containing the column, and the detection system.
• Gas chromatography currently uses capillary columns consisting of a fused silica, metal, glass or other material tube of very small inner diameter (typically from 0.05 mm to 0.53 mm), on the inner surface of which a constant thickness film of polymer material is deposited, to form the stationary phase. This thickness is generally between 0.05 ⁇ m and 5 ⁇ m depending on the column type, and is constant throughout the length of the column.
• the different mixture components have different affinities with the specific stationary phase of the column, they travel within the tube at different velocities, for which reason they can be separated along the gas chromatography column.
• the chemical composition of the stationary phase determines the types of components which can be separated by the gas chromatography column.
• Typical components of stationary phases are OV-1 , SE-1 (silicone based) or Carbowax 2OM (polyethyleneglycol based).
• the stationary phase hence depends on the substances to be analyzed and separated, on their chemical nature and in particular their volatility and polarity.
• Another drawback consists of the fact that when the glass connectors are subjected to thermal and mechanical stresses (due for example to the modulation systems applied to the 2DGC), the handling of the connected columns becomes problematic and can lead to their mutual disconnection. This sudden disconnection can itself have serious drawbacks both from the analytical and instrumental viewpoints.
• a column which no longer receives carrier gas and is at high temperature can easily degrade and irremediably lose its separative capacity, and likewise any mass spectrometer coupled to the gas chromatograph in the GC-MS method can be seriously damaged if it no longer receives carrier gas.
• a preferred embodiment of the present invention is further clarified hereinafter with reference to the accompanying drawing, showing a schematic longitudinal section through a portion of a gas chromatography column according to the invention.
• the gas chromatography column of the invention comprises a single continuous capillary tube 2 made of fused silica, metal or other material, in which two or more separate stationary phases 4, 6 of different nature and/or different thicknesses are deposited.
• the invention also includes all possible stationary phase combinations, i.e. stationary phases of different substances or of the same substance but of different thicknesses, or different substances of different thicknesses. These can be positioned one following the other without discontinuities, or can be separated by a portion of column 2 without stationary phases.
• the capillary column consists of two separate portions of different outer diameter, each of which presents one stationary phase, the two stationary phases being of different substances and/or thicknesses, as in the preceding example.

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• Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Biochemistry (AREA)
• General Health & Medical Sciences (AREA)
• General Physics & Mathematics (AREA)
• Immunology (AREA)
• Pathology (AREA)
• Treatment Of Liquids With Adsorbents In General (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=39532319

Family Applications (1)

Country Status (2)

Cited By (4)

Citations (6)

• 2007
  • 2007-06-01 IT IT000034A patent/ITVE20070034A1/it unknown
• 2008
  • 2008-04-21 WO PCT/EP2008/054807 patent/WO2008145457A1/en active Application Filing

Patent Citations (6)

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