Determination of stability constants and acute toxicity of potential hepatotropic gadolinium complexes.

Due to their high specificity for the hepatobiliary system, iminodiacetic acid derivatives are known to form a class of hepatobiliary agents. In this paper we present new hepatotropic gadolinium complexes to be used as potential MRI contrast agents. Derivatives of N-(2-phenylamine-2-oxoethyl) iminodiacetic acid are introduced as ligands into such complexes. In this way, we hope to achieve a valuable diagnostic tool for investigating of pathological changes in the liver. Stability constants of complexes were determined by potentiometric titration in 0.1 mol L(-1) NaNO3 solution at 20.0 +/- 0.1 degrees C. Stability and selectivity constants were also determined for endogenous metal ions such as Cu2+, Ca2+, and Zn2+ with the use of SUPERQUAD computer program. Acute toxicity of new gadolinium complexes was assessed in mice and histopathology examinations were carried out.

Gadolinium Gd(III) complexes with derivatives of nitriloacetic acid: synthesis and biological properties.

Combinations of nitrilotriacetic acid (NTA) derivatives with technetium 99mTc are known as convenient contrasting compounds used in nuclear medicine. Because of low resolution of this method, as well as necessity for using radioactive substances we have suggested new combinations of NTA aromatic derivatives with Gd(III). The aim of the undertaken study was to obtain contrasting compounds showing high affinity to liver cells enabling performance of high-resolution imaging of this organ applying the MRI. For presented complex compounds an efficient synthesis method was developed, and in vivo biodistribution tests were performed. The obtained derivatives showed strong affinity to hepatocytes, simultaneously showing differentiation depending on substituents located within the aromatic ring.