title: Dual Enzymatic Detection by Bulk Electrogenerated Chemiluminescence.
abstract: The combination of enzymes, as recognition elements for specific analytes, and of electrogenerated chemiluminescence (ECL) as a readout method has proven to be a valuable strategy for sensitive and specific analytical detection. However, ECL is intrinsically a 2D process which could potentially limit the analysis of inhomogeneous samples. Here, we show how a bulk ECL signal, generated by thousands of carbon microbeads remotely addressed via bipolar electrochemistry, are implemented as a powerful tool for the concomitant ECL sensing and imaging of two enzymatic substrates. We selected two enzymes (glucose dehydrogenase and choline oxidase) that react with their respective model substrates and produce in situ chemical species (β-nicotinamide adenine dinucleotide (NADH) and H2O2) acting as coreactants for the ECL emission of different luminophores ([Ru(bpy)3](2+) at λ = 620 nm and luminol at λ = 425 nm, respectively). Both enzymes are spatially separated in the same capillary. We demonstrate thus the simultaneous quantitative determination of both glucose and choline over a wide concentration range. The originality of this remote approach is to provide a global chemical view through one single ECL image of inhomogeneous samples such as a biochemical concentration gradient in a capillary configuration. Finally, we report the first proof-of-concept of dual biosensing based on this bulk ECL method for the simultaneous imaging of both enzymatic analytes at distinct wavelengths.
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Anne
authors.initials: A
authors.lastname: de Poulpiquet
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Diez-Buitrago
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Milena
authors.initials: M
authors.lastname: Dumont Milutinovic
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Milica
authors.initials: M
authors.lastname: Sentic
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Arbault
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Bouffier
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kuhn
authors.affiliation: University of Bordeaux , ISM, UMR 5255 CNRS, ENSCBP, 33607 Pessac, France.
authors.forename: Neso
authors.initials: N
authors.lastname: Sojic
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D002794:Choline / Q000032:analysis*; D005947:Glucose / Q000032:analysis*; D042843:Glucose 1-Dehydrogenase / Q000737:chemistry; D008163:Luminescent Measurements / Q000379:methods*; D008165:Luminol / Q000737:chemistry; D008958:Models, Molecular
chemical_list: D008165:Luminol; D000429:Alcohol Oxidoreductases; D042843:Glucose 1-Dehydrogenase; C019888:choline oxidase; D005947:Glucose; D002794:Choline