I am interested in derivitizing the hydroxyl groups of monosaccharide glycosides, such that following derivitization, the derivitized compound can be partitioned into organic solvent and injected for GC/MS analysis. Any references or procedures are appreciated.
By Anonymous on Saturday, November 16, 2002 - 08:49 am:
I'd try extracing with DMF solvent, then trimethylsilyl derivatization with something likeBSTFA, then GCMS on nonpolar capillary. That's what we've done in my lab with monosaccharides and sugar alcohols.
By Anonymous on Monday, November 18, 2002 - 11:46 am:
to last Anonymous:
do you quantitate the monosaccharides ?don't you have problems with the multiple peaks for each sugar?
and how do you extract with DMF,it's miscible in water!
By Anonymous on Monday, November 18, 2002 - 12:44 pm:
I don't get multiple peaks for each; if samples are too dilute to just dissolve in DMF at 2.5% water to DMF, dry first. If you want to derivatiize first, then extract into organic, you may need to make acetate derivatives using acetic anhydride.
By Anonymous on Tuesday, November 19, 2002 - 03:27 am:
you donīt get multiple peaks using BSTFA in monosaccharides?or are you using acetic anhydride?
please tell how!!!we are suffering here with the HPLC NH2 columns with RID because is difficult handle with 4 peaks of each sugar.
I know some ways to avoid multiple peaks :
Journal of Chromatography, 207 (198 1) 213
but is a four step derivatization.
and of course multiple peaks for monosaccharides:
Journal of Chromatography, 411 (1989) 205
Journal of Chromatography 462 (1989) 49
Journal of Chromatography, 398 (1987) 9
By Anonymous on Tuesday, November 19, 2002 - 08:43 am:
OK, in 1978 I used pyridine as solvent and made trimethylsilyl derivatives of dextrose, fructose, sorbitol, and sucrose, and analyzed on a non-polar packed column (fused-silica capillaries not available then) and obtained one peak for each. By 1982, we had obtained capillary GC, we used non-polar capillary for dextrose and sucrose in bacon, applicable to other monosaccharides as well. Used freeze-drying, oxime formation with hydroxylamine hydrochloride solution and heating, derivatize with TSIM derivatizing reagent; we used methyl-alpha-D-glucopyranoside as internal standard. Unfortunately, there were no computers in those days, so only typewritten material exists for this; reference was Pierce Handbook and General Catalog 1979-1980, pp. 182-184.
By Anonymous on Tuesday, November 19, 2002 - 10:05 am:
in 1978 did you use BSTFA?maybe weaker derivatives agents cold generate only one peak ,that's my theory.I've experienced this with some unsaturated lactones, long reaction times leads more silylated compounds(enol form).
do you perform this analyses today with the oxime formation step?
By Anonymous on Tuesday, November 19, 2002 - 11:04 am:
In 1978 we used Pierce Tri-Sil concentrate mixed with anhydrous pyridine. Not a whole lot of work with sugars since then (just sorbitol, for which we do use BSTFA).
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