Premium
Assessment of matrix effects and determination of niacin in human plasma using liquid–liquid extraction and liquid chromatography–tandem mass spectrometry
Author(s) -
Peoples Michael C.,
Halquist Matthew S.,
Ismaiel Omnia,
ElMammli Magda Y.,
Shalaby Abdalla,
Karnes H. Thomas
Publication year - 2008
Publication title -
biomedical chromatography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.4
H-Index - 65
eISSN - 1099-0801
pISSN - 0269-3879
DOI - 10.1002/bmc.1057
Subject(s) - chemistry , chromatography , extraction (chemistry) , niacin , liquid chromatography–mass spectrometry , analyte , liquid–liquid extraction , selected reaction monitoring , mass spectrometry , calibration curve , matrix (chemical analysis) , tandem mass spectrometry , detection limit , electrospray ionization , high performance liquid chromatography , biochemistry
A simple, sensitive and rapid liquid–liquid extraction method for the analysis of nicotinic acid (niacin) and its labeled internal standard nicotinic acid‐d4 (niacin‐d4) in human plasma was developed and validated. The analyte and its internal standard were isolated from acidified plasma using a single liquid–liquid extraction procedure with methyl‐ t ‐butyl ether. The extracted samples were analyzed by liquid chromatography–tandem mass spectrometry in positive electrospray ionization mode with multiple reaction monitoring. The calibration curves were linear in the measured range between 5 and 1000 ng/mL and the limit of detection was calculated as 122 pg/mL. The method required 250 µL of human plasma and the total run time between injections was 3.5 min. Matrix effects were assessed by post‐column infusion experiments, phospholipids monitoring and post‐extraction addition experiments. The extraction of phospholipids and niacin from plasma was studied under acidic, neutral and basic conditions. Acidic conditions were optimal for both the recovery of niacin and the removal of phospholipids; the degree of matrix effects for niacin was determined to be 2.5%. It was concluded that effective removal of matrix components can overcome low recovery issues associated with liquid–liquid extractions of polar analytes. Copyright © 2008 John Wiley & Sons, Ltd.