Development of a conjugated gadolinium and cisplatin–gelatin possessing properties as an intravascular contrast agent for MR imaging

PurposeThe purpose of this study is to create a Gd–DTPA–Gel–Cis compound, which made from gadolinum (Gd), diethylenetriaminepentaacetic acid (DTPA)-dianhydride, cis-diamminedichloroplatinum (Cis) and bovine gelatin (Gel), that makes it possible to visualize Cis as intravascular agent under magnetic resonance imaging (MRI).Materials and methodsThe amount of DTPA, Gd, and Cis were titrated to determine the new compound's conjugation ratio with gelatin. Considering these functions, Gd–DTPA–Gel–Cis was synthesized, and its stability in bovine serum was evaluated. In addition, the signal intensity of the diluted sample was measured under 1.5 Tesla MRI.ResultsThe synthesized 10 mg/ml of Gd–DTPA–Gel–Cis contained 42.84 μg/ml of Gd and 1.53 μg/ml of platinum. Gd–DTPA–Gel–Cis (100 mg/10 ml) enclosed into the cellulose dialysis tubing was placed in 90 ml of bovine serum and shaken reciprocally at 72 stroke/min at 37 °C. Partial release of free Pt was shown at 6 and 24 h, but no release of Gd occurred for a 24-h period. And high stability of Gd conjugated to DTPA–Gel–Cis. This result suggests possible anti-tumor effectiveness and high stability of Gd conjugated to DTPA–Gel–Cis. The diluted sample presented high signal intensity under 1.5 Tesla MRI.ConclusionGd–DTPA–Gel–Cis has been developed successfully and we have proven its stability and contrast ability in MRI.