Low nanogram detection of nucleotides using fast atom bombardment-mass spectrometry.
The effect of trimethylsilyl (TMS) derivatization on detection limits of mononucleotides in fast atom bombardment-mass spectrometry (FAB-MS) was examined. FAB-MS methods were developed to optimize sensitivity using adenosine 5'-monophosphate as a model compound and then applied to reference standards of two clinically important nucleotides: tricyclic nucleoside-5'-monophosphate (TCNMP) and 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP). The detection limit for the TMS derivative of TCNMP was 2.5-5 ng/microliters and less than 2.5 ng/microliters for FdUMP as its TMS derivative. This is greater than two orders of magnitude more sensitive than the FAB-MS analysis of the corresponding free compounds. These low detection limits for the TMS derivatives were obtained using a narrow scan range, signal averaging, detection in the negative ion mode, and 3-nitrobenzyl alcohol as the matrix. Hydrolysis of one or more of the labile TMS groups did occur, with the extent of hydrolysis being greatest in the more protic matrices.
Weng
Q M
QM
Department of Pharmaceutical Sciences, College of Pharmacy, University of Arizona, Tucson 85721.
Hammargren
W M
WM
Slowikowski
D
D
Schram
K H
KH
Borysko
K Z
KZ
Wotring
L L
LL
Townsend
L B
LB
D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D009711:Nucleotides / Q000032:analysis*
D009711:Nucleotides