title: Biomarkers and the sample matrix: challenges and opportunities.
authors.affiliation: PharmaCadence Analytical Services, LLC, Hatfield, PA 19440, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: King
authors.affiliation: PharmaCadence Analytical Services, LLC, Hatfield, PA 19440, USA.
authors.forename: Carmen
authors.initials: C
authors.lastname: Fernandez-Metzler
authors.affiliation: Virginia Commonwealth University, Department of Pathology, Richmond, VA 23298, USA.
authors.forename: Lorin M
authors.initials: LM
authors.lastname: Bachmann
keywords: LC–MS; biomarkers; quantitation; validation