Electrogenerated Chemiluminescence of Common Organic Luminophores in Water Using an Emulsion System

We describe a method to produce electrogenerated chemiluminescence (ECL) in water using a family of highly hydrophobic polycyclic aromatic hydrocarbon (PAH) luminophores and boron dipyrromethene (BODIPY). This method is based on an oil-in-water emulsion system. Various PAHs (rubrene, 9,10-diphenylanthracene, pyrene, or perylene) and BODIPY were trapped in a toluene and tri-n-propylamine mixed oil-in-water emulsion using an ionic liquid as the supporting electrolyte and emulsifier. ECL was observed for all the aforementioned PAHs and BODIPY, and the rubrene and BODIPY emulsion systems showed adequate light to record an ECL spectrum. ECL was also observed using oxalate as the co-reactant, which was dissolved in the aqueous continuous phase. The emulsions were stable for hours and showed a droplet size distribution that ranged from 275 to 764 nm, in accordance with dynamic light scattering data.