The assessment of pi-pi selective stationary phases for two-dimensional HPLC analysis of foods: application to the analysis of coffee.
Differences between alkyl, dipole-dipole, hydrogen bonding, and pi-pi selective surfaces represented by non-resonance and resonance pi-stationary phases have been assessed for the separation of 'Ristretto' café espresso by employing 2DHPLC techniques with C18 phase selectivity detection. Geometric approach to factor analysis (GAFA) was used to measure the detected peaks (N), spreading angle (beta), correlation, practical peak capacity (n(p)) and percentage usage of the separations space, as an assessment of selectivity differences between regional quadrants of the two-dimensional separation plane. Although all tested systems were correlated to some degree to the C18 dimension, regional measurement of separation divergence revealed that performance of specific systems was better for certain sample components. The results illustrate that because of the complexity of the 'real' sample obtaining a truly orthogonal two-dimensional system for complex samples of natural origin may be practically impossible.
Mnatsakanyan
Mariam
M
Australian Centre for Research on Separation Science, University of Western Sydney Node, School of Natural Sciences, Parramatta, NSW, Australia.
Stevenson
Paul G
PG
Shock
David
D
Conlan
Xavier A
XA
Goodie
Tiffany A
TA
Spencer
Kylie N
KN
Barnett
Neil W
NW
Francis
Paul S
PS
Shalliker
R Andrew
RA
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003069:Coffee / Q000737:chemistry*; D013058:Mass Spectrometry
D003069:Coffee