Optimisation and routine use of generic ultra-high flow-rate liquid chromatography with mass spectrometric detection for the direct on-line analysis of pharmaceuticals in plasma
J. Ayrton et al., Optimisation and routine use of generic ultra-high flow-rate liquid chromatography with mass spectrometric detection for the direct on-line analysis of pharmaceuticals in plasma, J CHROMAT A, 828(1-2), 1998, pp. 199-207
The use of ultra-high flow-rate chromatography coupled to mass spectrometry
offers great potential for the rapid, on-line analysis of pharmaceutical c
ompounds in plasma as it permits high throughput direct analysis of plasma
samples without any time-consuming sample preparation such as solid-phase e
xtraction. The coupling of mass spectrometry with high performance liquid c
hromatography often results in enhanced selectivity and sensitivity compare
d to, for example, ultraviolet absorbance detection. This can remove the ne
ed for complete resolution of the analyte from endogenous materials in the
matrix. The use of large particle size stationary phases, and therefore, th
e ability to use large porosity column end frits, coupled with the added se
lectivity and sensitivity of the mass spectrometer allows an on-line analys
is approach to be used for the direct analysis of pharmaceuticals in biolog
ical matrices with extremely high throughput. This paper presents an overvi
ew of the manner in which we have optimised this technique for the analysis
of plasma samples, in terms of gradient profile, system configuration and
optimal injection volume for maximum throughput and robustness. The nature
of the mobile phase flow is also discussed. (C) 1998 Published by Elsevier
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