Gas Chromatography
Gas Chromatography (GC) is a widely used technique for the separation and characterization of complex mixtures due to its versatility, and also due to its wide field of application in all branches of Science.
In Gas Chromatography, the compounds of a vaporized sample are separated by a process of partitioning between a gaseous mobile phase and a stationary phase fixed on a column. The function of the gaseous mobile phase is to transport the analytes through the column. It is an inert gas and therefore does not interact in the process.
- We can classify Gas Chromatography as a second or separation method:
- Gas-liquid chromatography: The stationary phase is a liquid fixed on an inert solid packing or fixed to the walls of a capillary column. Most applications are carried out using this process.
- Gas-solid chromatography: The stationary phase is solid and retention is carried out by means of an adsorption mechanism. The adsorption process is not linear and the application of this mechanism has many limitations.
Once separated, the compounds are detected using a specific detector, generating a characteristic signal that depends on both the type of compound and its concentration. The graphical representation of the signal versus the retention time of the compounds is called a chromatogram.
Instrumental Facilities
Gas Chromatograph:
- Agilent 7820 A coupled to Agilent 5975 MSD mass detector..
- Agilent 7820 FID detector (flame ionization)..
Accessory:
Components:
- Chromatograph: thermoscientific trace 1600.
- Triple quadrupole mass analyzer: thermoscientific tsq9610
Applications
Gas chromatography (GC) is a powerful and versatile analytical technique used to separate and quantify the volatile components of a mixture.
QUALITATIVE ANALYSIS:
Identification of the components of a mixture. As mentioned above, by using an FT-IR or mass spectrometer as a detector, we have access to the complete spectrum of the eluent for any retention time. By interpreting the spectrum or searching a spectral library, we can identify the analyte responsible for each chromatographic peak.
QUANTITATIVE ANALYSIS:
Gas chromatography is widely used for the analysis of a wide variety of samples in environmental, clinical, pharmaceutical, biochemical, forensic, food science and petrochemical laboratories. Some of its applications are shown in the table.
Environment | Pesticides in wastewater, and ground. Trihalomethanes in water. PAH´S. |
Clinical | Drugs. Blood alcohol. |
Forensic | Accelerators of fire. Explosives detection. |
Consumer products | VOC´S. Monomers in materials. |
Petrochemistry | Solvent purity. Hydrocarbon composition. |
| Feeding | Fatty acid profiles. |
| Cosmetics | Aromas and fragrances. |
Sample requirements
- Documentation to be submitted: Fully Filled Service Form
- Minimum sample quantity required: 0-100µL (please consult us)
- Maximum number of samples per application: 10
- Injection volume: 1-10µL
- Filtration if possible: 0.45µm
- Time frame for collecting measured samples: 1 month
- Refrigeration of analyzed samples: 1 week after delivery of results
More information
| Jorge Millos | Alberto Acuña | José Gómez |
| +34 986 812 238 | +34 986 813 885 | |
| jmillos@uvigo.es | berto@uvigo.es | josegomez@uvigo.es |