The invention is directed to a lanthamide chelate composition having a lanthamide, a charged amidate ligand, and a mono- or bidentate neutrally charged coordination compound, the composition being represented by structure I or structure II wherein Ln3+ designates lanthamide, R1 is alkyl, aryl, or heteroaryl; R2 is alkyl, aminoalkyl, aryl or heteroaryl; M is a neutrally charged monodentate coordination compound, M′ is a neutrally charged bidentate coordination compound, a=1 or 2; and wherein M and M′ comprise N, S, or O. It extends to the process of making the composition.