INVESTIGADORES
CERUTTI Estela Soledad
congresos y reuniones científicas
Título:
Metabolic profiling of carnitine, acylcarnitines, amino acids, and other metabolites in plasma samples by monolithic and HILIC HPLC-ESI-TOF-MS
Autor/es:
ESTELA SOLEDAD CERUTTI; TIMOTHY GARRETT; PEGGY BORUM; JODIE V. JOHNSON; RICHARD A. YOST; DAVID H. POWELL
Lugar:
Denver, Colorado, Estados Unidos
Reunión:
Conferencia; 56th ASMS Conference on Mass Spectrometry and Allied Topics; 2008
Institución organizadora:
American Society for Mass Spectrometry
Resumen:
Acidic
conditions were used to promote the protonation of some of the
compounds under study. Thus, the positive ESI and APCI normal mass
spectra were dominated by the presence of the [M+H]+ ions with minimal
fragmentation. On the contrary, ammonium acetate was used to enhance
deprotonation of those metabolites more easily ionized in negative mode
ESI and APCI. In addition, in order to facilitate a better spectral
correlation, LC methodologies not including any buffer addition were
evaluated.
In addition, two different column approaches were compared, a small
particle packed column and a silica-based monolithic column. Similar
chromatographic resolution was obtained with both columns. The
chromatographic profile of eluting compounds was analogous for both
column approaches. Rapid, comprehensive, and high-resolution metabolite
separation was achieved. Our studies involved a large number of samples
that required powerful data analysis capabilities. In this sense, the
raw instrument data were processed in several steps by the instrument
software. From the obtained chromatograms, features, molecular entities
obtained using mass and retention times, were extracted, aligned,
normalized, statistically processed, and finally identified. This
process resulted in the extraction of > 1,000 feature groups, from
which approximately >300 compounds had a S/N ratio greater than
nine. Calibration curves have been obtained for a suite of
acylcarnitines. Amino acids, lipids, and phospholipids will be included
in the data presented. The analytical separation/detection strategy and
the analysis steps were also used to evaluate technical variability
(sample preparation, instrumental response, etc.). The methodology will
be discussed and the results of these analyses will be presented.