Nanoscale packed capillary liquid chromatography-electrospray ionization mass spectrometry: analysis of penicillins and cephems.
A series of seventeen penicillins and cephems (cephalosporins and cephamycins) was examined by electrospray ionization. Separations by nanoscale packed-capillary liquid chromatography, with sub-microliter flow-rates, were performed using methanol-water and acetonitrile-water both containing trifluoroacetic acid gradients. In the on-column analyses, the protonated species usually predominate, and the fragment ions are often present which can be used for confirmation of compound identity. With combined nanoscale packed-capillary liquid chromatography-electrospray ionization mass spectrometry, separations and full-scan mass spectra can be obtained on *q12-15 ng of analyte, allowing the analysis of therapeutic levels of these antibiotics from only a few microliters of serum.
Laboratory of Molecular Biophysics, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709.
C E
CE
Parker
J R
JR
Perkins
K B
KB
Tomer
Y
Y
Shida
K
K
O'Hara
D002439:Cefotaxime / Q000097:blood; D002511:Cephalosporins / Q000097:blood*; D002513:Cephamycins / Q000097:blood*; D002853:Chromatography, Liquid; D006801:Humans; D013058:Mass Spectrometry; D010406:Penicillins / Q000097:blood*; D010878:Piperacillin / Q000097:blood; D012015:Reference Standards
D002511:Cephalosporins; D002513:Cephamycins; D010406:Penicillins; D002439:Cefotaxime; D010878:Piperacillin