1. Lang R, Wahl A, Skurk T, Yagar EF, Schmiech L, Eggers R, Hauner H, Hofmann T: Development of a hydrophilic liquid interaction chromatography-high-performance liquid chromatography-tandem mass spectrometry based stable isotope dilution analysis and pharmacokinetic studies on bioactive pyridines in human plasma and urine after coffee consumption. Anal Chem. 2010 Feb 15;82(4):1486-97. doi: 10.1021/ac902616k. [PubMed:20073472 ]