Electrogeneration of polyluminol and chemiluminescence for new disposable reagentless optical sensors

A performant reagentless electrochemiluminescent (ECL) detection system for H₂O₂ is presented, based on an electropolymerized polyluminol film prepared under near-neutral conditions. Such an original polyluminol electrodeposition is reported for the first time and on a screen-printed electrode (SPE) surface. Electropolymerized luminol acts as an active luminophore of the electrochemiluminescent reaction, as the monomer does. Polymerization conditions have been optimized in order to obtain the best ECL responses to H₂O₂. By performing electrodeposition in a potentiostatic mode, at 425 mV vs. Ag|AgCl, in 0.1 mol L⁻¹ phosphate/0.1 mol L⁻¹ KCl pH 6 and 1 mmol L⁻¹ luminol, with a total charge of 0.5 mC, the linear range for H₂O₂ detection extends from 7.9 × 10⁻⁸ mol L⁻¹ to 1.3 × 10⁻³ mol L⁻¹. Such performant disposable reagentless easy-to-use miniaturized systems based on SPEs should be applicable to the electrochemiluminescent detection of many oxidase-substrate compounds. Figure An original polyluminol electrodeposition process on a screen-printed electrode surface is reported for the first time. The polymeric structure is demonstrated to behave as an electrochemiluminescent luminophore, allowing disposable reagentless easy-to-use optical sensors for hydrogen peroxide detection to be designed.