INVESTIGADORES
CERUTTI Estela Soledad
congresos y reuniones científicas
Título:
UPLC and monolithic HPLC/ESI-MS and MS/MS determination of carnitine and acylcarnitines
Autor/es:
SOLEDAD CERUTTI; TIMOTHY GARRET; PEGGY R. BORUM; JODIE V. JOHNSON; RICHARD A. YOST; DAVID H. POWELL
Lugar:
Indianapolis, Indiana, Estados Unidos
Reunión:
Conferencia; 55th ASMS Conference on Mass Spectrometry and Allied Topics; 2007
Institución organizadora:
American Society for Mass Spectrometry
Resumen:
Due to the
zwitterionic nature of acylcarnitines, acidic conditions were used to
promote protonation of the carboxylic group, which resulted in the
production of positively charged quaternary amines. Thus, the positive
ESI normal mass spectra of acylcarnitines were dominated by their [M+H]+ ions with minimal fragmentation.
Collision-induced dissociation (CID) of the acylcarnitines [M+H]+
ions was accomplished via the conventional mass-selected method on the
triple quadrupole and via the non-mass-selected in-source CID on the
oa-TOF-MS. The effects of CID energy were investigated with each
instrument.
The acylcarnitines [M+H]+ ions underwent CID on both instruments to produce similar product ions. The major product ions were m/z 60, [(CH3)3NH]+, and m/z 85, [CH2CHCHCOOH]+ and product ions resulting from a common neutral loss of (CH3)3N
(59 u) and from the loss of the carnitine backbone (161 u). The TQ
MS/MS technique yielded the more informative fragmentation patterns,
especially for the least abundant product ions. Useful fragmentation
fingerprints were also obtained with source collision-induced
dissociation on the oa-TOF but with the higher m/z resolution and
accuracy. Compared to the 1.8 μm particle size C18 HPLC column, higher
chromatographic resolution was obtained with the very small particle
silica-based monolithic column. The gradient time was greatly reduced.
The chromatographic profile of eluting acylcarnitines was dramatically
improved using this rapid gradient. Rapid, comprehensive, and
high-resolution acylcarnitine separation for metabolomics was achieved.
The methodology will be discussed and the results of these analyses
will be presented, together with the results of our ongoing studies for
profiling acylcarnitines in clinical samples.