title: Metabonomics of newborn screening dried blood spot samples: a novel approach in the screening and diagnostics of inborn errors of metabolism.
abstract: A novel, single stage high resolution mass spectrometry-based method is presented for the population level screening of inborn errors of metabolism. The approach proposed here extends traditional electrospray tandem mass spectrometry screening by introducing nanospray ionization and high resolution mass spectrometry, allowing the selective detection of more than 400 individual metabolic constituents of blood including acylcarnitines, amino acids, organic acids, fatty acids, carbohydrates, bile acids, and complex lipids. Dried blood spots were extracted using a methanolic solution of isotope labeled internal standards, and filtered extracts were electrosprayed using a fully automated chip-based nanospray ion source in both positive and negative ion mode. Ions were analyzed using an Orbitrap Fourier transformation mass spectrometer at nominal mass resolution of 100,000. Individual metabolic constituents were quantified using standard isotope dilution methods. Concentration threshold (cutoff) level-based analysis allows the identification of newborns with metabolic diseases, similarly to the traditional electrospray tandem mass spectrometry (ESI-MS/MS) method; however, the detection of additional known biomarkers (e.g., organic acids) results in improved sensitivity and selectivity. The broad range of detected analytes allowed the untargeted multivariate statistical analysis of spectra and identification of additional diseased states, therapeutic artifacts, and damaged samples, besides the metabolic disease panel.
authors.affiliation: Biomolecular Medicine, Department of Surgery and Cancer, Imperial College London, United Kingdom.
authors.forename: Júlia
authors.initials: J
authors.lastname: Dénes
authors.forename: Eszter
authors.initials: E
authors.lastname: Szabó
authors.forename: Steven L
authors.initials: SL
authors.lastname: Robinette
authors.forename: Ildikó
authors.initials: I
authors.lastname: Szatmári
authors.forename: László
authors.initials: L
authors.lastname: Szőnyi
authors.forename: Joachim G
authors.initials: JG
authors.lastname: Kreuder
authors.forename: Ernst W
authors.initials: EW
authors.lastname: Rauterberg
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Takáts
mesh_terms: D042964:Acyl-CoA Dehydrogenase / Q000172:deficiency / Q000378:metabolism; D059788:Dried Blood Spot Testing / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn; D008052:Lipid Metabolism, Inborn Errors / Q000175:diagnosis* / Q000378:metabolism*; D055432:Metabolomics / Q000379:methods*; D015997:Neonatal Screening / Q000379:methods*; D010661:Phenylketonurias / Q000175:diagnosis* / Q000378:metabolism*; D015203:Reproducibility of Results
chemical_list: D042964:Acyl-CoA Dehydrogenase