title: Improved method to determine succinylacetone in dried blood spots for diagnosis of tyrosinemia type 1 using UPLC-MS/MS.
abstract: We describe an improved diagnostic method for tyrosinemia type 1 based on quantifying succinylacetone in dried blood spots by ultra-performance liquid chromatography tandem mass spectrometry. Succinylacetone extracted from a single 3/16 inch disk of specimen collection paper containing a dried blood spot was derivatized with dansylhydrazine, separated on an Acquity UPLC BEH C(18) column (2.1 x 50 mm, 1.7 microm) and detected by electrospray ionization tandem mass spectrometry. Succinylacetone derivative eluted at 0.6 min with a complete run time of 1 min. Using a 13C4 labeled succinylacetone as an internal standard, the calibration plot was linear up to 100 micromol/L with a detection limit (S/N = 3) of 0.2 micromol/L. Intra-day (n = 13) and inter-day (n = 10) variations were better than 10%. The cutoff level of succinylacetone in dried blood spots from healthy infants obtained by the current method was 0.63 micromol/L (n = 151). In dried blood spots from patients with established tyrosinemia type 1 (n = 11), concentration of succinylacetone was 6.4-30.8 micromol/L.
authors.affiliation: National Laboratory for Newborn Screening, Department of Genetics, King Faisal Specialist Hospital and Research Centre, PO Box 3354, Riyadh 11211, Saudi Arabia. dirbashi@kfshrc.edu.sa
authors.forename: Osama Y
authors.initials: OY
authors.lastname: Al-Dirbashi
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Rashed
authors.forename: Minnie
authors.initials: M
authors.lastname: Jacob
authors.forename: Lujane Y
authors.initials: LY
authors.lastname: Al-Ahaideb
authors.forename: Mohamed
authors.initials: M
authors.lastname: Al-Amoudi
authors.forename: Zuhair
authors.initials: Z
authors.lastname: Rahbeeni
authors.forename: Moeen M
authors.initials: MM
authors.lastname: Al-Sayed
authors.forename: Zuhair
authors.initials: Z
authors.lastname: Al-Hassnan
authors.forename: Mohamed
authors.initials: M
authors.lastname: Al-Owain
authors.forename: Hamad
authors.initials: H
authors.lastname: Al-Zeidan
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006537:Heptanoates / Q000097:blood* / Q000737:chemistry; D006801:Humans; D016014:Linear Models; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D020176:Tyrosinemias / Q000097:blood / Q000175:diagnosis*
chemical_list: D006537:Heptanoates; C020804:succinylacetone