Synthesis and Characterization of 3,4,3-LI(1,2-HOPO) Ligand

The ligand 3,4,3-LI(1,2-HOPO) was synthesized and characterized by Ash Stevens, Inc. (Detroit, MI) as previously described.^{4 (link)} Purity was determined to be 97.3% by high performance liquid chromatography (HPLC) analysis (data not shown). All other chemicals were obtained from commercial suppliers and used as received. Purified deionized water, using Millipore Milli-Q reverse osmosis, was used to prepare aqueous solutions. Pooled plasma samples and male and female liver microsomes from Sprague Dawley rat, beagle dog, and human were purchased from Bioreclamation, Inc. (Hicksville, NY). All samples were stored at −80°C until use. Either [¹³C₄]-3,4,3-LI(1,2-HOPO), with a chemical purity of 99.3% (Moravek Biochemicals, Inc., Brea, CA), or ethyl nicotinate (Sigma Chemicals, St. Louis, MO) was used as the internal standard during the liquid chromatography coupled with mass spectrometric (LC-MS or LC-MS/MS) analyses.