I am a student, learning and working on a Varian GC. I was given the task to calibrate our new GC in the lab. Can anyone please advice on the suitable internal standard that I should use if I am interested in C12-C18 fatty alcohol?
Thanks in advance.
By Anonymous on Wednesday, November 6, 2002 - 11:37 pm:
An internal standard should be a substance wich is chemically alike to the anlytes you want to quantify. So using an alcohol (C8 or C10) would be a good starting point
By Anonymous on Friday, November 8, 2002 - 12:22 pm:
Actually, I would use tridecanol or pentadecanol, obtainable from aldrich in quite pure form. I usually make trimethylsilyl derivatives of the fatty alcohols to improve peak shape also.
By jimmy pendergrass on Thursday, January 30, 2003 - 01:18 pm:
getting started using gc/ms to quantitate steroid hormones in plasma; looking for class offering wet lab for hands-on training w/internal std calibration using deuterated std's (isotope dilution mass spectrometry. if anyone knows where such training is available, please let me know. thanx.
By Rodney on Friday, January 31, 2003 - 11:42 am:
For an analysis that is more sensitive to branched chains I would use an acetate derivative instead of the TMS ether. Both may be adequate but if branched chains are to be separated then I would make acetates. In the 1980s when I changed this analysis my std went from 99% to 94% in purity. If you want the same carbon number alcohols to elute together, then use the TMS ether.