ABSTRACT
In little more than three decades, electrogenerated chemiluminescence (ECL) has moved from being a “laboratory curiosity” to being a useful analytical technique. Metal chelates, in particular the dication of tris(bipyridine)ruthenium(II), Ru(bpy)32+ (bpy = 2,2′-bipyridine), have played a pivotal role in this transformation. This is not surprising, considering that many metal chelates display the electrochemical and spectroscopic qualities required of ECL luminophores (Chapter 1). Representative systems include main group metals (e.g., Si and Al) [1,2], transition metal complexes incorporating Ru, Os, and Pt [3-8], and rare earth chelates [9,10], to name a few. There has been particular emphasis on characterizing the nature of the excited state, discerning the mechanisms by which this state is formed, and determining the efficiency of excited state formation. Various techniques were used and are still being used, including detailed electrochemical studies, spectroscopic and spin-resonance measurements, and magnetic field effects (Chapters 1-4) [3,11,12].
