Article pubs.acs.org/ac
Measurement of Lung Phosphatidylcholines in Exhaled Breath Particles by a Convenient Collection Procedure Shahid Ullah,*,† Sören Sandqvist,‡ and Olof Beck†,‡ †
Department of Laboratory Medicine, Karolinska Institute, 14183 Stockholm, Sweden Department of Clinical Pharmacology, Karolinska University Laboratory, 14186 Huddinge, Sweden
‡
ABSTRACT: An analytical method based on high-performance liquid chromatography coupled to quadrupole tandem mass spectrometry was developed for the quantitative determination of four phosphatidylcholines (PCs) in human exhaled breath particles. Analytes were conveniently collected on an electrostatic polymer filter and extracted with methanol prior to analysis. Chromatographic separation was performed on an ultraperformance liquid chromatographic ethylene bridged hybrid phenyl column using a mobile phase consisting of water and methanol containing 4 mM ammonium formate and 0.1% ammonia. The mass spectrometer operated in positive electrospray ionization and selected reaction monitoring mode. Detection limits for PC 16:0/16:0 (dipalmitoylphosphatidylcholine, DPPC), PC 16:0/18:1, PC 16:0/18:2, and PC 18:0/18:2 were
