title: Multianalyte electrochemical biosensor on a monolith electrode by optically scanning the electrical double layer.
abstract: Redox on an electrode is an interfacial phenomenon that modulates the charge in the electrical double layer (EDL). A novel instrument, the Scanning Electrometer for Electrical Double-layer (SEED) has been developed to measure multiple enzyme reactions on a monolith electrode due to immunospecific binding with a mixture of respective analytes. SEED quantitatively maps the local redox reaction by scanning a laser on the array of enzyme monolayer spots immobilized on the monolith electrode. SEED measures the change in local charge state of the EDL that abruptly changes due to the redox reaction. The measurement spot size defined by the size of the laser beam is ~10 µm. The SEED signal is linearly proportional to the local redox current density and analyte concentration. The specificity is close to 100%. The SEED readout is compatible with microfluidics platform where the signal degrades less than 2% due to the poly(dimethyl siloxane) (PDMS) body.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln (UNL), 207 Othmer Hall, Lincoln, NE 68588-0643, USA.
authors.forename: Seung-Woo
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln (UNL), 207 Othmer Hall, Lincoln, NE 68588-0643, USA. Electronic address: rsaraf@unlnotes.unl.edu.
authors.forename: Ravi F
authors.initials: RF
authors.lastname: Saraf
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D004867:Equipment Design; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D010084:Oxidation-Reduction; D040081:Protein Array Analysis / Q000295:instrumentation*
chemical_list: D004800:Enzymes, Immobilized
keywords: Biosensor; Differential interferometer; Electrical double layer; Electrochemical sensor; Microarray; Multianalyte sensor