Electrochemiluminescent rhenium moieties and methods for their use

A chemical moiety having the formula

• (Re(P).sub.m (L.sup.1).sub.n (L.sup.2).sub.o (L.sup.3).sub.p (L.sup.4).sub.q).sub.t (B).sub.u
• wherein
• P is a bidentate aromatic heterocyclic nitrogen-containing ligand of Re selected from the group consisting of bipyridyl, substituted bipyridyl, bipyrazyl, substituted bipyrazyl, phenanthrolyl and substituted phenanthrolyl, wherein each of said substituted groups is substituted by an alkyl, aryl, aralkyl, carboxylate, carboxaldehyde, carboxamide, cyano, amino, hydroxycarbonyl, hydroxyamino, aminocarbonyl, amidine, guanidinium, ureide, sulfur-containing group, phosphorous-containing group, or the carboxylate ester of N-hydroxysuccinimide;
• L.sup.1, and L.sup.2, independently of one another, each is a bidentate aromatic heterocyclic nitrogen-containing ligand of Re selected from the group consisting of bipyridyl, substituted bipyridyl, bipyrazyl, substituted bipyrazyl, phenanthrolyl and substituted phenanthrolyl, wherein each of said substituted groups is substituted by an alkyl, aryl, aralkyl, carboxylate, carboxaldehyde, carboxamide, cyano, amino, hydroxycarbonyl, hydroxyamino, aminocarbonyl, amidine, guanidinium, ureide, sulfur-containing group, phosphorous-containing group, or the carboxylate ester of N-hydroxysuccinimide;
• or is a monodentate ligand selected from the group consisting of carbon monoxide, cyanides, isocyanides, halides, and aliphatic, aromatic and heterocyclic phosphines, amines, stilbines, and arsines;
• and
• each of L.sup.3, and L.sup.4 is a monodentate ligand selected from the group consisting of carbon monoxide, cyanides, isocyanides, halides, aliphatic, aromatic and heterocyclic phosphines, amines, stilbines, and arsines;
• each of P, L.sup.1, L.sup.2, L.sup.3, and L.sup.4 being the same or not the same as each other ligand;
• B is a whole cell, subcellular particle, polypeptide, nucleic acid, polysaccharide, alkaloid, steroid, vitamin, amino acid, or nonbiological polymer which is conjugated to one or more of P, L.sup.1, L.sup.2, L.sup.3 and L.sup.4 ;
• m is an integer equal to or greater than 1;
• each of n, o, p and q is zero or an integer;
• t is an integer equal to or greater than 1;
• and
• u is an integer equal to or greater than 1;
• P, L.sup.1, L.sup.2, L.sup.3, L.sup.4, and B being of such composition and number that the chemical moiety can be induced to electrochemiluminesce and the total number of bonds to Re provided by the ligands of Re being equal to the coordination number of Re.