chromatography
Posted: Fri Mar 04, 2005 3:45 pm
What are the advantages and disadvantages of 2-dimensional chromatography and high performance chromatography?
In order to look for compounds which are hidden under a large amount of hydrocarbons or other not useful background (e.g samples from fuel, food, natual matrix) you can either use a very powerful MS detector or use a multidimensional GC. Usually the cost of a multidimensional GC is much less, but more complicated in usage.
So called multidimensional GCs usually cut out a short peak (typically 5s to 30s) from the first column and transfer it to a much slower, thick film column with a different film (active phase) to separte that peak in even more analytes.
A high performance system can be a triplequad MS, sector MS etc. These instruments can be a few 100K$, while MDGC can cost as little as 10K$ or less.
Regards,
Ingo Christ