{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T14:52:57Z","timestamp":1790434377821,"version":"4.1.0"},"reference-count":6,"publisher":"SAGE Publications","issue":"5","license":[{"start":{"date-parts":[[2011,7,20]],"date-time":"2011-07-20T00:00:00Z","timestamp":1311120000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Ann Clin Biochem"],"published-print":{"date-parts":[[2011,9]]},"abstract":"\n Background<\/jats:title>\n Branched chain amino acid (BCAA) analysis is needed for the diagnosis and management of patients with maple syrup urine disease (MSUD). We report an improved ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS\/MS) method for the determination of BCAAs and Allo-Ile in dried blood spot (DBS) samples.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n BCAAs were extracted from a 3 mm blood spot into methanol\/water containing stable isotope internal standards. Eluents were dried and reconstituted in the mobile phase. Gradient elution was performed on an Acquity\u2122 BEH C\n 18<\/jats:sub>\n (100 \u00d7 2.1 mm, 1.7 \u03bcm) column. BCAAs were detected and quantified in the multiple reaction monitoring mode in a five-minute analysis.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n The assay was calibrated to give best possible alignment with plasma results. Retrospective analysis of newborn DBSs from six classic MSUD patients showed elevated alloisoleucine (Allo-Ile) in all cases. Two of four patients with mild disease had normal values; the other two had significant elevations in Allo-Ile.<\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n Analysis of BCAA in DBS by UPLC-MS\/MS is a useful second tier newborn screening test to identify classical MSUD and for monitoring of remote patients.<\/jats:p>\n <\/jats:sec>","DOI":"10.1258\/acb.2011.010283","type":"journal-article","created":{"date-parts":[[2011,7,20]],"date-time":"2011-07-20T23:00:54Z","timestamp":1311202854000},"page":"468-470","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":25,"title":["An improved ultra performance liquid chromatography-tandem mass spectrometry method for the determination of alloisoleucine and branched chain amino acids in dried blood samples"],"prefix":"10.1177","volume":"48","author":[{"given":"A","family":"Alodaib","sequence":"first","affiliation":[{"name":"Discipline of Paediatrics and Child Health, University of Sydney"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"K","family":"Carpenter","sequence":"additional","affiliation":[{"name":"Discipline of Paediatrics and Child Health, University of Sydney"},{"name":"NSW Biochemical Genetics Service, The Children's Hospital at Westmead, Sydney, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V","family":"Wiley","sequence":"additional","affiliation":[{"name":"Discipline of Paediatrics and Child Health, University of Sydney"},{"name":"NSW Newborn Screening Programme"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"K","family":"Sim","sequence":"additional","affiliation":[{"name":"NSW Biochemical Genetics Service, The Children's Hospital at Westmead, Sydney, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"Christodoulou","sequence":"additional","affiliation":[{"name":"Discipline of Paediatrics and Child Health, University of Sydney"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B","family":"Wilcken","sequence":"additional","affiliation":[{"name":"Discipline of Paediatrics and Child Health, University of Sydney"},{"name":"NSW Newborn Screening Programme"},{"name":"NSW Biochemical Genetics Service, The Children's Hospital at Westmead, Sydney, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2011,7,20]]},"reference":[{"key":"bibr-ACB-10-283C1","doi-asserted-by":"publisher","DOI":"10.1373\/clinchem.2007.098434"},{"key":"bibr-ACB-10-283C2","doi-asserted-by":"publisher","DOI":"10.1093\/clinchem\/45.10.1734"},{"key":"bibr-ACB-10-283C3","doi-asserted-by":"publisher","DOI":"10.1016\/S0378-4347(01)00100-1"},{"key":"bibr-ACB-10-283C4","doi-asserted-by":"publisher","DOI":"10.1016\/j.ymgme.2009.11.010"},{"key":"bibr-ACB-10-283C5","doi-asserted-by":"publisher","DOI":"10.1093\/clinchem\/41.1.62"},{"key":"bibr-ACB-10-283C6","doi-asserted-by":"publisher","DOI":"10.1007\/s10545-006-0366-0"}],"container-title":["Annals of Clinical Biochemistry: International Journal of Laboratory Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1258\/acb.2011.010283","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1258\/acb.2011.010283","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1258\/acb.2011.010283","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T11:56:28Z","timestamp":1777377388000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1258\/acb.2011.010283"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,7,20]]},"references-count":6,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2011,9]]}},"alternative-id":["10.1258\/acb.2011.010283"],"URL":"https:\/\/doi.org\/10.1258\/acb.2011.010283","relation":{},"ISSN":["0004-5632","1758-1001"],"issn-type":[{"value":"0004-5632","type":"print"},{"value":"1758-1001","type":"electronic"}],"subject":[],"published":{"date-parts":[[2011,7,20]]}}}