title: Quantitative mass spectrometry methods for pharmaceutical analysis.
abstract: Quantitative pharmaceutical analysis is nowadays frequently executed using mass spectrometry. Electrospray ionization coupled to a (hybrid) triple quadrupole mass spectrometer is generally used in combination with solid-phase extraction and liquid chromatography. Furthermore, isotopically labelled standards are often used to correct for ion suppression. The challenges in producing sensitive but reliable quantitative data depend on the instrumentation, sample preparation and hyphenated techniques. In this contribution, different approaches to enhance the ionization efficiencies using modified source geometries and improved ion guidance are provided. Furthermore, possibilities to minimize, assess and correct for matrix interferences caused by co-eluting substances are described. With the focus on pharmaceuticals in the environment and bioanalysis, different separation techniques, trends in liquid chromatography and sample preparation methods to minimize matrix effects and increase sensitivity are discussed. Although highly sensitive methods are generally aimed for to provide automated multi-residue analysis, (less sensitive) miniaturized set-ups have a great potential due to their ability for in-field usage.This article is part of the themed issue 'Quantitative mass spectrometry'.
authors.affiliation: KU Leuven, Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, Herestraat 49, 3000 Leuven, Belgium.
authors.forename: Glenn
authors.initials: G
authors.lastname: Loos
authors.affiliation: KU Leuven, Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, Herestraat 49, 3000 Leuven, Belgium.
authors.forename: Ann
authors.initials: A
authors.lastname: Van Schepdael
authors.affiliation: KU Leuven, Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, Herestraat 49, 3000 Leuven, Belgium deirdre.cabooter@pharm.kuleuven.be.
authors.forename: Deirdre
authors.identifier: http://orcid.org/0000-0001-5502-5801
authors.initials: D
authors.lastname: Cabooter
mesh_terms: D006801:Humans; D007553:Isotope Labeling; D013058:Mass Spectrometry / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D004364:Pharmaceutical Preparations / Q000032:analysis*; D012015:Reference Standards
chemical_list: D004364:Pharmaceutical Preparations
keywords: hyphenated techniques; internal standards; mass spectrometry; matrix effects; pharmaceutical analysis; sample preparation