Hi, I am doing derivatization of luteolin (standard) for GCMS analysis. My derivatization reagent is BSTFA and TMCS (99:1 ratio). I tried diferent temperature (60, 70,80,110) and time (15min, 30min,45min,60min), but still cannot find my luteotin. Can anyone give me any suggetstions?
Flavonoids are aromatic compounds occuring in plants usually are biosynthesized by three importnat pathways 1. Acetate melonate pathway 2. Acetatae mevalonate pathwy and 3. Shikimic acid pathway. Flavonoids have mixed biogenesis and they are obtained from more than one or two or more the pathways.They posses flavonoid ring system and isoflavonoid ring system, ring A is derived from 3 acetate units, joined head to tail while ring B is formed of three carbon atoms of the pyran ring derived from cinnamic acid.Chalcones may be regarded as the precursor of all three classes of flavonoids. Silybin is derived from flavonoids.
Dear Dr. Pei Han,
I am not sure why you chose GC-MS for Luteolin analysis.
Use HPLC- MS instead. You need not derivatise luteolin. You can directly inject, identify, and quantitate by LC MS. It is much simpler and accurate
Regards
This may seem obvious; however, this derivation is very sensitive to water contaimination. If your sample is dry, the reaction should be quantitative. You may not wish to switch to LC-MS at this point in your analysis, though that appears an option if available. Good luck.
I tried as well this way (derivatization with BSTFA wih GC-MS analysis) of kaempferol, myricetin, syringetine. I think it's not a problem of derivatization but analysis choice. I never succeed to see these derivatized flavonoids.
Have you tried this: to dry sample add anhydrous(and fresh) pyridine e.g. 50 ul. Vortex for a while and then add silylation agents. Remember to do blanks --- lot of odd stuff originating from pyridine and silylation reagents.
Dear Pey Han,
May I have the two papers that you talked about?
Thank you.