kaasukromatografiamassspektrometrialla

Kaasukromatografiamassaspektrometria, often abbreviated as GC-MS, is a powerful analytical technique used to separate, identify, and quantify compounds in a sample. It combines the separation capabilities of gas chromatography (GC) with the detection and identification power of mass spectrometry (MS).

In a GC-MS system, the sample is first introduced into a gas chromatograph. Here, it is vaporized and then passed through a long, narrow column coated with a stationary phase. Different components of the sample travel through the column at different rates based on their physical and chemical properties, such as volatility and affinity for the stationary phase, leading to their separation.

As each separated component exits the GC column, it enters the mass spectrometer. In the MS, the molecules are ionized, typically by electron ionization. These ions are then separated based on their mass-to-charge ratio (m/z) using a magnetic or electric field. The MS detector records the abundance of ions at each m/z value, generating a mass spectrum.

The mass spectrum serves as a unique "fingerprint" for each compound, allowing for its identification by comparing it to spectral libraries. Furthermore, the intensity of the signals in the mass spectrum can be used to determine the concentration of the identified compounds in the original sample. GC-MS is widely employed in various fields, including environmental monitoring, forensic science, food safety, and pharmaceutical analysis, due to its high sensitivity and specificity.