Working Principle:

Its core principle is to utilize the difference in forces between the mobile and stationary phases of each component in the mixture to achieve separation. Mobile phase: usually a random gas such as nitrogen, helium, etc., like a conveyor belt, responsible for carrying the sample from head to tail. Fixed phase: a special substance applied to the inner wall of a chromatographic column, which exhibits varying degrees of affinity with different components in the sample.

Analysis process: from injection to peak extraction

1. Sample transformation and transportation, usually liquid or gas entering the instrument through an injector. In the high-temperature gasification chamber, the liquid sample instantly turns into gas. Then the carrier gas will act like a human tool, carrying these vaporized molecules into the separation core - the chromatographic column.

2. Separation battle in chromatographic column: This is a crucial step, as different components in the sample repeatedly interact with the stationary phase in the chromatographic column. The components with weak affinity do not match the fixed ones, and they stay in the column for a short time, run fast, and will rush out. The parts with strong affinity, which are sticky with the fixed ones, stay for a long time and come out after running slowly.

Detector recognition and signal conversion:

The components that run out of the chromatographic column in sequence will enter the detector. The detector will capture their presence and convert it into an electrical signal. Common detectors include FID (flame ionization detector) and TCD (thermal conductivity detector)

Data becomes visible results:

The electrical signal is received by the workstation and ultimately generates a chromatogram. Each peak on the graph represents a component. Retention time: The time when the peak appears, used for qualitative analysis (to determine which substance it is) Peak area/peak height: The size of the peak is used for quantitative calculation of the content of the modified substance