The present invention is directed, in general, to a contrast agent comprising a tetraazacyclododecane ligand and comprising a macrocyclic ring and a paramagnetic metal ion coordinated to the tetraazacyclododecane ligand. Pendent arms R, R, R" and R" attached to a ring nitrogen. The pendent arms have the general formula: -CHR¹R² and for three or more of the pendant arms a chirality of the carbon atoms C are identical for each of three or more of the pendant arms. The R¹ group is larger than hydrogen and R² is selected from the group consisting of: an alcohol, amides, a carboxylate, phosphinates and a phosphonate. One or more substituents R⁶ is a group larger than a methyl group and is located on one or more ring carbons.