What are the differences, advantages and disadvantages between GC and GC?

The advantage of chromatography is separation, which provides the most effective choice for the separation of mixtures. However, it is difficult to obtain the structural information of substances, and it mainly depends on the comparison with standard substances to judge unknown substances. The detection of compounds without ultraviolet absorption needs to be analyzed by other means. Mass spectrometry can provide structural information of substances, and the amount of samples used is very small, but the samples to be analyzed need to be purified and have a certain purity before they can be directly analyzed. Therefore, it is expected to combine chromatography and mass spectrometry to make up for their respective shortcomings.

HLPC-MS can analyze compounds with strong polarity, difficult volatilization and thermal instability that cannot be analyzed by gas chromatography-mass spectrometry (GC-MS), and it also has the following advantages:

① The analysis range is wide, and MS can detect almost all compounds, thus easily solving the analysis problem of thermally unstable compounds;

② Strong separation ability, even if the analyzed mixture is not completely separated in chromatography, their respective chromatograms can be given by ms characteristic ion mass spectrometry for qualitative and quantitative analysis;

③ The qualitative analysis results are reliable, and the molecular weight and rich structural information of each component can be given at the same time;

④ Low detection limit and high MS sensitivity. By selecting the ion detection (SIM) mode, its detection ability can be improved by more than one order of magnitude.

⑤ The analysis time is fast, and the liquid chromatographic column used by HPLC-MS is a narrow-diameter column, which shortens the analysis time and improves the separation effect;

⑥ High degree of automation, high degree of HPLC-MS automation.