1. Structure and working principle: Gas chromatography-mass spectrometry (GC-MS) is a device that adds a mass spectrometry detector to the gas chromatograph. The gas chromatograph uses gas as the carrier gas, heats and evaporates the sample into the gas phase, and transmits it along the chromatographic column to the detector. The gas chromatography-mass spectrometer also uses gas as the carrier gas to heat and evaporate the sample into the gas phase. However, after chromatography, the sample molecules are ionized by an ion source, producing an ion flow that is transmitted to the mass spectrometry detector for detection. After analysis by the analyzer, the signal is recorded by the detector to obtain information on the sample composition. Therefore, gas chromatography-mass spectrometry has the dual advantages of gas chromatography-mass spectrometry.
2. Sensitivity and Resolution: Due to the addition of a layer of mass spectrometry detector on top of the gas chromatograph, the sensitivity and resolution of the gas chromatography-mass spectrometer are higher than those of the gas chromatography-mass spectrometer. Gas chromatography-mass spectrometry can analyze more complex samples and detect compounds with very low content.
3. Cost: Compared to gas chromatographs, gas chromatography-mass spectrometry (GC-MS) has an additional layer of mass spectrometry detector, so its cost is also higher than that of gas chromatographies. Suitable for situations where high requirements are placed on detection accuracy, analysis depth, and sensitivity in research.
In summary, gas chromatography-mass spectrometry (GC-MS) combines gas chromatography-mass spectrometry (GC-MS) with a mass spectrometry detector, which can analyze more complex samples with higher sensitivity and resolution. It is suitable for situations where high detection accuracy, analysis depth, and sensitivity are required in research, but the cost is also higher.