title: Three-dimensional interdigitated electrode array as a transducer for label-free biosensors.
abstract: A new transducer for biosensor applications has been developed based on a three-dimensional interdigitated electrode array (IDEA) with electrode digits separated by an insulating barrier. Binding of molecules to a chemically modified surface of the transducer induces important changes in conductivity between the electrodes. Three-dimensional sensor shows considerable improvement compared with a standard planar IDEA design. The potential of the developed device as a sensor transducer to detect immunochemical and enzymatic reactions, as well as DNA hybridization events is demonstrated. The immunosensor allows direct detection of the antibiotic sulfapyridine and shows the IC(50) parameter value of 5.6 microgL(-1) in a buffer. Immunochemical determination occurs under competitive configurations and without the use of any label. Each modified sensor is of a single use. Nevertheless, biochemical reagents can be easily cleaned off the sensor surface for its reuse. Layer-by-layer method of used to deposit polyethyleneimine and glucose oxidase showed that the sensor is also highly effective for detecting single and multilayered molecular assemblies.
authors.affiliation: Chemical Transducers Group, Instituto de Microelectronica de Barcelona, Centro Nacional de Microelectrónica (CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Andrey
authors.initials: A
authors.lastname: Bratov
authors.forename: Javier
authors.initials: J
authors.lastname: Ramón-Azcón
authors.forename: Natalia
authors.initials: N
authors.lastname: Abramova
authors.forename: Angel
authors.initials: A
authors.lastname: Merlos
authors.forename: Javier
authors.initials: J
authors.lastname: Adrian
authors.forename: Francisco
authors.initials: F
authors.lastname: Sánchez-Baeza
authors.forename: Maria-Pilar
authors.initials: MP
authors.lastname: Marco
authors.forename: Carlos
authors.initials: C
authors.lastname: Domínguez
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation*; D008839:Microelectrodes; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling; D014159:Transducers