{"id":1309,"date":"2017-05-11T08:30:05","date_gmt":"2017-05-11T12:30:05","guid":{"rendered":"\/\/phytochemia.com\/?p=1309"},"modified":"2017-05-11T08:30:05","modified_gmt":"2017-05-11T12:30:05","slug":"do-it-faster-makes-us-stronger-fast-gc","status":"publish","type":"articles-de-blogue","link":"https:\/\/phytochemia.com\/en\/articles-de-blogue\/do-it-faster-makes-us-stronger-fast-gc\/","title":{"rendered":"Do It Faster, Makes Us Stronger – Fast GC"},"content":{"rendered":"

Benoit Roger, Ph. D., & Alexis St-Gelais, M. Sc., chimiste<\/p>\n

We have read many times on various oils-oriented Facebook groups indications that gas chromatographic columns should be as long as possible to achieve proper separation. Similarly, it is often stated that short analysis runs negatively impact the quality of data obtained. And under the most generally used conditions to perform gas chromatography, both of these statements are true.<\/p>\n

But this does not mean that they are always true.<\/p>\n

If you take a look at, for example, our blogpost about serrata-type frankincense<\/a>, you will notice that the total run time for the chromatogram depicted was a bit over 20 minutes. This clashes with the almost 100 minutes used by many laboratories, and even our standard 60-minutes runs depicted in our reports dating from 2015 to this day. But comparing strictly on the basis of time is misleading in this case. This is because the frankincense serrata run was made under full fast GC<\/strong> conditions; our usual reports are done under semi-fast GC conditions; and most other labs work with conventional (non-fast) GC.<\/p>\n

So wait, what it that fast GC thing? We apologize in advance, because the explanation is a little tedious. We try below to present it as simply as possible. It all is a matter of reducing the time needed for an analysis.<\/p>\n

Let\u2019s go back to the beginning. Since the introduction of gas chromatography and the development of capillary column in the 1950s [1], considerable research has been conducted to enhance the efficiency of GC systems. Among other points to improve: the separation speed\u2026 Short analytical time meant higher throughput and lower costs for analytical labs. It also allowed to have faster answers in continuous process control and gave the possibility to replicate analysis in an acceptable time [2]. Principles and theory of fast GC were established in 1960s but to this day, it still is relatively rarely encountered, except in some research papers, and it keeps an aura of novelty [3]. Columns suitable for this purpose are still less often sold, and even sometimes outright unavailable.<\/p>\n

Here are the founding principles of fast GC as they are presented in a document from Supelco [4]\u2013 a very good read to go a bit more in depth. The retention time of a given compound, and thus analytical time, can be determined using several complex equations. Three key parameters can be modified to achiever shorter runs [5] :<\/p>\n