Popularization
8 September 2014
Alexis St-Gelais – Popularization I wrote some time ago about retention indices in GC-FID and the advantages of using two columns to analyze an essential oil. Since this is a central aspect of the work we do using GC, I wished to detail a real-case analysis, allowing you to better understand our methodology. Throughout the
Popularization
2 September 2014
Alexis St-Gelais – Popularization [Minor addenda to the original text were made on March 23, 2019, and are noted in green] An important task of analytical chemistry is to select the detector that best suits the purpose of an analysis. Each detector has indeed its pros and cons. In the area of essential oils, FID and
Popularization
25 August 2014
Alexis St-Gelais – Popularization I mentioned in the first post of this series on GC analyzes that PhytoChemia resorted simultaneously to two capillary columns to analyze essential oils, one polar (Solgel-Wax) and one non-polar (DB-5). The rationale behind this technique will reveal some of the art of interpreting essential oils profiles. We have seen that
Popularization
18 August 2014
Alexis St-Gelais – Popularization My last post gave some details about a detection method commonly used in GC, the FID. Another detector that is widely used for the analysis of volatile compounds, including at PhytoChemia, is the mass spectrometer (MS). Unlike the FID, the MS is a complex detector. Typically, in GC-MS (although other modes
Popularization
11 August 2014
Alexis St-Gelais – Popularization The first part of this series dealt with the principles of separation of volatile molecules upon analysis by GC. After their separation, the analyst has yet to be able to detect molecules as they leave the capillary column, either to identify or quantify them. At PhytoChemia, we mainly use two types
Popularization
4 August 2014
Alexis St-Gelais – Popularization Many of the samples we analyze are sent to us directly as essential oils. However, sometimes a customer wishes to compare plants before their extraction. He may also need a measure of oil yield so that he can plan ahead larger extractions. In these cases, we use two main extraction techniques, each with