Patent ID: 7371579

Claim:
A labeled nickel complex compound having formula I: wherein: B independently represents doubly bonded oxygen; C represents carbon; D independently represents nitrogen or oxygen; L is a detectable label, optionally attached to a linker; M represents a nickel ion; b is from 0 to 6; n is 0 to 1; R′ represents hydrogen, alkyl, aryl or a peptide chain; R″ is R, R′ or G; G represents OH, an amide or a DNA delivery agent; and R represents a nitrogen-containing cationic group, optionally attached to a linker, wherein said cationic group is at least one C b group linked to a nitrogen atom, (CH 2 ) 3 NH 2 , (CH 2 ) 2 NH 2 , C b N (C b ) 0-3 , pyridyl.