Identification of anomeric configuration of underivatized reducing glucopyranosyl-glucose disaccharides by tandem mass spectrometry and multivariate analysis.
The possibility of discrimination of the anomeric configuration (alpha or beta) of underivatized reducing glucopyranosyl-glucose disaccharides, using a hybrid mass spectrometer Q-TOF 2 (Micromass), a linear ion trap LXQ (Thermo), and a triple quadrupole Quattro (Micromass) with an electrospray source (ESI) was investigated. Differences observed in the relative abundances of specific product ions obtained from collisionally induced dissociation of the [M + Li]+ adducts were statistically analyzed, and discriminant analysis was performed. MANOVA has shown that anomeric configuration has influence on the combined dependent variables (relative abundances of m/z product ions) in all the three mass spectrometers used (Q-TOF 2, LIT, and QqQ). Discriminant analysis has shown that, in all instruments, it is possible to discriminate anomeric configurations and to build a diagnostic model. These diagnostic differences are even more relevant considering that no derivatization procedures are needed for obtaining this structural information. The Q-TOF 2 instrument has been shown to give data that allowed us to build a model with better discriminant power (Wilks' lambda value of 0.014) followed by the QqQ instrument (Wilks' lambda value of 0.029) and the LIT instrument (Wilks' lambda value of 0.037).
Simões
Joana
J
Department of Chemistry, University of Aveiro, P-3810-193 Aveiro, Portugal.
Domingues
Pedro
P
Reis
Ana
A
Nunes
Fernando M
FM
Coimbra
Manuel A
MA
Domingues
M Rosario M
MR
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000032:analysis / Q000737:chemistry*; D005947:Glucose / Q000031:analogs & derivatives* / Q000032:analysis; D007477:Ions / Q000737:chemistry; D008969:Molecular Sequence Data; D015999:Multivariate Analysis; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods*
D004187:Disaccharides; D007477:Ions; D005947:Glucose