Early use of gas chromatography stationary liquids

In 1950, Martin, the inventor of gas chromatography, used diatomaceous earth (Celite) as a carrier, silicone oil (DC 550) as a stationary liquid, and gas as a mobile phase to separate ammonia, fatty amines, and pyridine homologues. DC 550 (methyl polysiloxane containing 25% phenyl) was originally an industrial high-temperature resistant silicone oil.

After Martin used silicone oil (polysiloxane) as a gas chromatography stationary liquid, he pioneered the use of polysiloxane as a gas chromatography stationary liquid. However, polysiloxane based stationary liquids were not yet dominant at that time, most people still use various low molecular weight compounds. In 1956, someone proposed a "standard" fixed solution: n-hexadecane, squalane, benzyl biphenyl, nonyl phthalate, dimethylformamide, and diglycidyl. (J.Chromatogr.Sci. 1973,11(4):216)。

Later, some high polymers were also used as gas chromatography stationary liquids, such as polyethylene glycol, various polyesters, and various lubricating greases extracted from petroleum, such as apisone-L and apisone-M, etc. Some of the polysiloxane fixing liquids used at that time were also industrial products, such as DC-550, DC-710, QF-1, DC-11, SE-30 (polydimethylsiloxane). Afterwards, polydimethylsiloxane became a widely used GC fixing solution.

In 1964, someone proposed 58 commonly used fixing liquids, and the top ten most frequently used stationary liquids were apison-L SE-30, Dinonyl phthalate, squalane PEG 20M, Adipic acid ethylene glycol polyester PEG 400, DC 550, Tricresyl phosphate PEG 1500.

In order to adapt to the separation of various mixtures, stationary liquids have sprung up like mushrooms after rain, and over 700 types of gas chromatography stationary liquids were collected in the gas chromatography data compilation DS 25 A S-1 published in 1972.

In the era where gas chromatography was mainly based on packed columns, because of the limited column efficiency of packed columns, for separating various mixtures, people have researched and developed thousands of stationary liquids, but the excessive amount of stationary liquids has brought new troubles. For this, Many people are dedicated to studying the classification of stationary liquids and selecting the most commonly used stationary liquids. The most influential ones are stationary liquids meters of Rohrschneider and McReynolds's.

Since the emergence of elastic quartz capillary columns in 1979, capillary gas chromatography has experienced rapid development. The trend of replacing packed columns with capillary columns is becoming increasingly evident, especially with the development and application of thick liquid film capillary columns with large inner diameters in 1983. The emergence of excellent gas solid chromatography capillary columns - PLOT columns - has offset the remaining advantages of packed columns.

Some people believe that capillary columns have extraordinary high column efficiency, which reduces the requirement for selectivity of stationary liquids, as long as there are three capillary columns (polydimethylsiloxane, polyethylene glycol 20M, cyano polydimethylsiloxane), 80% of analytical tasks can be completed. But to solve complex mixtures with high boiling points, various isomers with similar boiling points, and optical isomers with extremely similar properties, it is necessary to use a new, highly thermally stable, reproducible, and selectively selective stationary liquids. So over the years, researchers have synthesized numerous stationary liquids that suitable for capillary columns.