title: Extraction methods for the removal of phospholipids and other endogenous material from a biological fluid.
abstract: BACKGROUND
  A comparison of three different sample preparation techniques for the analysis of plasma samples has been investigated to highlight the effect that these approaches have on the removal of endogenous material. The three techniques under investigation are: SPE, support assisted liquid-liquid extraction and nonspecific solvent-based protein precipitation.
  
  
  RESULTS
  Comparisons are made on the practicalities of each approach and to allow a semiquantitative assessment between the effectiveness of these different techniques the relative amounts of phospholipids present within the sample are analyzed. Total ion chromatograms are also obtained to further study the effects of different extraction techniques in the removal of endogenous components from a biological matrix. Both of these approaches provide a very coarse measure of the cleanliness of the extracts and demonstrate that support assisted liquid-liquid extraction and an optimized SPE approach remove a greater amount of endogenous material.
  
  
  CONCLUSIONS
  This study highlights the importance of sample preparation in removing endogenous material, which may have a detrimental effect on the performance of a bioanalytical assay.
authors.affiliation: Department of Clinical Pharmacology & Drug Metabolism & Pharmacokinetics, AstraZeneca Pharmaceuticals, Alderley Park, Macclesfield, Cheshire, UK.
authors.forename: F
authors.initials: F
authors.lastname: Michopoulos
authors.forename: A M
authors.initials: AM
authors.lastname: Edge
authors.forename: Y-T
authors.initials: YT
authors.lastname: Hui
authors.forename: T
authors.initials: T
authors.lastname: Liddicoat
authors.forename: G
authors.initials: G
authors.lastname: Theodoridis
authors.forename: I D
authors.initials: ID
authors.lastname: Wilson
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000737:chemistry; D011232:Chemical Precipitation; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D059625:Liquid-Liquid Extraction; D010743:Phospholipids / Q000302:isolation & purification*; D010949:Plasma / Q000737:chemistry*; D051381:Rats; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D001798:Blood Proteins; D010743:Phospholipids