Use of trifluoroacetic acid to quantify small, polar compounds in rat plasma during discovery-phase pharmacokinetic evaluation
Although it is accepted that trifluoroacetic acid (TFA) can cause suppression of an analyte during LC/MS analysis, this paper presents a relatively sensitive gradient method that uses a TFA mobile phase for the improved quantification of small, polar drug-like compounds. The described method was dev...
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Published in | Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Vol. 856; no. 1; pp. 165 - 170 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier B.V
01.09.2007
Elsevier Science |
Subjects | |
Online Access | Get full text |
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Summary: | Although it is accepted that trifluoroacetic acid (TFA) can cause suppression of an analyte during LC/MS analysis, this paper presents a relatively sensitive gradient method that uses a TFA mobile phase for the improved quantification of small, polar drug-like compounds. The described method was developed in a discovery drug metabolism and pharmacokinetics (DMPK) laboratory for the screening measurement of compound concentrations to calculate PK parameters and CNS exposure of compounds from a chemical series that had poor chromatography under generic methods using formic acid mobile phase. The samples were collected by a Culex automated sampling unit, and the plasma proteins were precipitated by a Tecan robot in 96-well plates. After centrifugation, the supernatant was removed, dried down using a SPE-Dry unit, and the samples were reconstituted in aqueous buffer on the robot. The samples were analyzed on an Agilent LC/MSD using a 5-min gradient on a 5
cm phenyl column. No additional steps, such as the “TFA-fix”, were necessary. Although sample batches were analyzed over 6
h, no drift or degradation of signal was observed. The improved chromatography resulted in a method that was selective, rugged, and had a dynamic range from 5 to 20,000
nM, which was sufficient to quantitate low volume, serial plasma samples collected out to 8
h postdose. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1570-0232 1873-376X |
DOI: | 10.1016/j.jchromb.2007.05.024 |