Electrochemiluminescence of Water-Soluble Poly(amidoamine) Dendrimers Conjugated with Multiple Ru(II) Tris(bipyridine) Moieties.

Intense electrochemiluminescence (ECL) of water-soluble dendritic conjugates, which are poly(amidoamine) (PAMAM) dendrimers conjugated with multiple Ru(II) tris(bipyridine) ([Ru(bpy)₃]²⁺, where bpy=2,2'-bipyridine) units on the periphery, is demonstrated in the absence of any additional co-reactant. The ECL results were investigated by taking into account the co-reactant effect of PAMAM dendrimers. The water-soluble dendritic conjugates were synthesized by derivatizing amine-terminated 4^th-generation PAMAM dendrimers (G4-NH₂) through covalent linkages with [Ru(bpy)₃]²⁺- N-hydroxysuccinimide esters. Interestingly, the synthesized dendritic conjugates alone exhibit significantly enhanced oxidative-reduction ECL, that is, an approximate nine-fold increase compared to conventional ECL obtained from corresponding aqueous mixtures of free G4-NH₂ dendrimers and [Ru(bpy)₃]²⁺ complexes. [ABSTRACT FROM AUTHOR]