Equipment supercritical fluid chromatography

In supercritical fluid chromatography (SFC) the mobile phase is a supercritical fluid, such as carbon dioxide [15]. A supercritical fluid can be created either by heating a gas above its critical temperature or compressing a liquid above its critical pressure. Generally, an SFC system typically has chromatographic equipment similar to a HPLC, but uses GC columns. Both GC and LC detectors are used, thus allowing analysis of samples that cannot be vaporized for analysis by GC, yet cannot be detected with the usual LC detectors, to be both separated and detected using SFC. SFC is also in other... 

The major difference in supercritical fluid chromatography and conventional LC equipment is the pumping systems as well as the safety features installed to maintain higher pressure. Unique SFC equipment differences are ... 

Equipment for supercritical fluid chromatography is similar to that for HPLC with packed columns12 or open tubular columns. Eluent strength is increased in HPLC by gradient elution and in gas chromatography by raising the temperature. In supercritical... 

The use of unbonded silica has tended to be limited to techniques such as adsorption chromatography and supercritical fluid chromatography (SFC) [8,9] which are important techniques, but by no means as widespread as their dominant reversed-phase LC cousin. A number of reasons can be suggested for this including their biological incompatibility, the use of specialist equipment (in SFC) and the use of... 

Chromatography. GC is the most common anal)d ical method used but liquid and supercritical fluid chromatographic methods are being increasingly developed. Like titration the sample is destroyed in the analysis process. The ideal situation depicted in Figure 8.8 cannot normally be applied for titration or chromatographic analysis since the analysis equipment needs to be close to the sampling device. This is often termed at-line analysis. 

SFC, in which the mobile phase is a supercritical fluid, is a hybrid of gas chromatography (GC) and liquid chromalography (I.C) that combines some of the best features of each. For certain applications, it is superior to both GC and UPLC. In 1985 several instrument manufacturers began to offer equipment spccilically designed for SI C. and the use of such equipment is expanding at a rapid pace. The SFC technique has become an important tool in many industrial, regulatory, and academic laboratories. 

Analytical systems do equip almost all laboratories. Many different kinds of particle sizes are used from 20 to 2 [tm (from HPLC to UPLC), using liquid or supercritical fluid mobile phases. An intermediate market is to be considered using 10 mm ID columns for small-scale purifications. The term preparative chromatography is dedicated to purification units using column diameters from 50 up to 1600 mm ID. 

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