title: Miniaturized optical chemosensor for flow-based assays.
abstract: A cost-effective, highly compact, and versatile optoelectronic device constructed of two ordinary light emitting diodes compatible with optosensing films has been developed. This fibreless device containing chemoreceptor, semiconductor light source, and detector integrated in a miniaturized flow-through cell of low microliter internal volume works as a complete photometric chemical sensor suitable for detection in flow analysis. The operation of the developed device under nonstationary programmable-flow conditions offered by sequential injection analysis has been demonstrated using Prussian Blue film as a model optical chemoreceptor. The unique spectroelectrochemical properties of the sensing material enable its use for optical sensing of redox species, whereby ascorbic acid and hydrogen peroxide have been chosen as model analytes. The reported SI-sensor system features fast and reproducible determination of both analytes in the submillimolar range of concentrations. The construction concept demonstrated in this work can be easily applied to other kinds of optical sensors based on absorbance sensing films.
authors.affiliation: Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Pokrzywnicka
authors.forename: David J
authors.initials: DJ
authors.lastname: Cocovi-Solberg
authors.forename: Manuel
authors.initials: M
authors.lastname: Miró
authors.forename: Víctor
authors.initials: V
authors.lastname: Cerdà
authors.forename: Robert
authors.initials: R
authors.lastname: Koncki
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Tymecki
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D005295:Ferrocyanides / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000032:analysis; D008567:Membranes, Artificial; D055095:Optics and Photonics / Q000295:instrumentation*; D010084:Oxidation-Reduction; D010777:Photochemistry
chemical_list: D005295:Ferrocyanides; D008567:Membranes, Artificial; D006861:Hydrogen Peroxide; D001205:Ascorbic Acid; C000170:ferric ferrocyanide