title: A simple method for the analysis by MS/MS of underivatized amino acids on dry blood spots from newborn screening.
abstract: The analysis by electrospray-ionization tandem mass spectrometry of amino acids with butyl esterification and isotopically labeled internal standard is routine in newborn screening laboratories worldwide. In the present study, we established a direct analysis method of higher accuracy that uses a non-deuterated internal standard. The automatic sampler and the pump of an LC apparatus were used to inject sample and mobile phase to MS, but no LC column was needed. The dry blood spot (DBS) material was prepared at levels of low, medium and high concentration; the running time was 1 min. In parallel to the new procedure, we applied the established method to analyze nine amino acids on DBS of healthy newborns and phenylketonuria newborns. The newly proposed method of product ion confirmation scan along with multiple reaction monitoring resulted in a very accurate identification of each amino acid. Our innovative protocol had high sensitivity and specificity in the analysis of cases of suspected metabolic diseases.
authors.affiliation: Chang Chun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, People's Republic of China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Wang
authors.forename: Wenyan
authors.initials: W
authors.lastname: Zhang
authors.forename: Fengrui
authors.initials: F
authors.lastname: Song
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Liu
authors.forename: Shuying
authors.initials: S
authors.lastname: Liu
mesh_terms: D000596:Amino Acids / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn; D008659:Metabolic Diseases / Q000097:blood*; D015997:Neonatal Screening; D010661:Phenylketonurias / Q000097:blood; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000295:instrumentation* / Q000379:methods*
chemical_list: D000596:Amino Acids