Patent ID: 7371524

Claim:
A macrocyclic fluorescent ligand with a central metal atom, said atom having two non-polymeric axial ligands, one on either side of the macrocycle, said axial ligands being chosen from the group consisting of alkoxy, halide, hydroxy, borate, sulfate or phosphate, said macrocycle having one or more benzo groups and as ring substituents on one benzo ring, two ortho carboxy groups or one carboxy group together with one other non-carboxy group having a negative charge at pH 5 or greater in aqueous solutions, and as other ring substituents at any other possible position on the macrocycle one or more non-carboxy groups having a negative charge at pH 5 or greater in aqueous solution, said macrocyclic fluorescent ligand capable of labeling compounds having less red absorbance compared to blue absorbance such that when conjugation of said macrocyclic fluorescent ligand is complete the ratio of the absorbance at 681 nm/350 nm (A red/A blue) is less than 1.5.