Determination of the MRI contrast agent Gd-DTPA by SEC-ICP-MS.
The simultaneous determination of Gd(3+) and Gd-DTPA (DTPA: diethylenetriamino-pentaacetic acid), often used as contrast agent, is described. The proposed approach combines size-exclusion chromatography (SEC) and inductively coupled plasma-mass spectrometry (ICP-MS) for element-selective detection in order to determine also high-molecular Gd-complexes if present. This method was applied to the analysis of urine samples of a patient to whom Gd-DTPA was intravenously administered. The results showed that no conversion or adsorption of Gd-DTPA could be observed in any sample, even free Gd(3+) could not be detected. Urine excretion behaviour was monitored and it was proved that Gd-DTPA was almost completely (>99%) excreted by urination within one day. Traces of Gd-DTPA could be measured in hair samples, but extraction with tetramethylammonium hydroxide (TMAH) resulted in degradation of Gd-DTPA.
Loreti
Valeria
V
Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg-University of Mainz, Duesbergweg 10-14, 55099 Mainz, Germany.
Bettmer
Jörg
J
D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D003287:Contrast Media / Q000737:chemistry*; D005682:Gadolinium / Q000032:analysis* / Q000737:chemistry / Q000652:urine; D019786:Gadolinium DTPA / Q000737:chemistry* / Q000652:urine; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D012680:Sensitivity and Specificity; D013997:Time Factors
D003287:Contrast Media; D005682:Gadolinium; D019786:Gadolinium DTPA