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Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
Fluorometric determination of EDTA and EGTA using terbium-salicylate complex
1Biology Department, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA. yclee@jhu.edu
Abstract:
A method for determining EDTA (ethylenediaminetetraacetic acid) based on a highly fluorescent terbium-EDTA-salicylic acid complex formation was developed. EDTA from as low as a few picomoles to as high as several nanomoles can be determined in a microtiter plate in 10-20 min. Ethyleneglycol-bis(2-aminoethoxy)-tetraacetic acid (EGTA) also can be determined by the same method, but its sensitivity is ca. 14-fold lower. Interestingly, diethylenetriamine tetraacetic acid did not form fluorescent complex with terbium under the same conditions.
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