Quantification and excretion kinetics of a magnetic resonance imaging contrast agent by capillary electrophoresis-mass spectrometry.
A novel method for the analysis of Gadolinium-based contrast agents in complex clinical matrices is presented. Three commonly applied ionic contrast agents for magnetic resonance imaging were separated by CE and detected by ESI-MS. Blank urine samples were spiked with Dotarem (Gd-DOTA, Gadolinium-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), Magnevist (Gd-DTPA, Gadolinium-diethylenetriaminepentaacetic acid) and Multihance (Gd-BOPTA, Gadolinium-benzyloxymethyl-diethylenetriaminepentaacetic acid) to determine the recovery rates. The figures of merit were determined with LODs as low as 2.0 x 10(-7) mol/L for Gd-DOTA, 5.0 x 10(-7) mol/L for Gd-DTPA and 1.0 x 10(-6) mol/L for Gd-BOPTA. The respective LOQs were 6.6 x 10(-7) mol/L for Gd-DOTA, 1.5 x 10(-6) mol/L for Gd-DTPA and 3.3 x 10(-6) mol/L for Gd-BOPTA. The linear working range comprised two orders of magnitude starting at the LOQ, with regression coefficients of R > or = 0.999 for all investigated analytes. Using this CE-MS method, Gd-DOTA was quantified in seven urine samples obtained at different times after delivery from a volunteer magnetic resonance imaging patient who was treated with Dotarem. Additionally, total Gd concentrations were determined by means of ICP-optical emission spectroscopy to validate the CE-MS data. To compensate for dietary dilution effects of the urine samples, creatinine was determined by HPLC with UV/Vis absorption detection. Gd-DOTA concentrations were normalized to urinary creatinine, illustrating the fast excretion kinetics of Gd-DOTA.
University of Münster, Institute of Inorganic and Analytical Chemistry, Münster, Germany.
Jens
J
Künnemeyer
Lydia
L
Terborg
Sascha
S
Nowak
Christine
C
Brauckmann
Lena
L
Telgmann
Anastasia
A
Albert
Faruk
F
Tokmak
Bernhard K
BK
Krämer
Andreas
A
Günsel
Gerhard A
GA
Wiesmüller
Uwe
U
Karst
D000328:Adult; D003287:Contrast Media / Q000032:analysis* / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D019786:Gadolinium DTPA / Q000737:chemistry / Q000652:urine; D006571:Heterocyclic Compounds / Q000737:chemistry / Q000652:urine; D006801:Humans; D007089:Image Enhancement; D007700:Kinetics; D008279:Magnetic Resonance Imaging; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D008536:Meglumine / Q000031:analogs & derivatives / Q000737:chemistry / Q000652:urine; D009942:Organometallic Compounds / Q000737:chemistry / Q000652:urine
D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate; D019786:Gadolinium DTPA