0000000000013499

AUTHOR

Juliana Chawich

0000-0003-1599-4450

showing 3 related works from this author

Regenerable ZnO/GaAs Bulk Acoustic Wave Biosensor for Detection of Escherichia coli in “Complex” Biological Medium

2021

A regenerable bulk acoustic wave (BAW) biosensor is developed for the rapid, label-free and selective detection of Escherichia coli in liquid media. The geometry of the biosensor consists of a GaAs membrane coated with a thin film of piezoelectric ZnO on its top surface. A pair of electrodes deposited on the ZnO film allows the generation of BAWs by lateral field excitation. The back surface of the membrane is functionalized with alkanethiol self-assembled monolayers and antibodies against E. coli. The antibody immobilization was investigated as a function of the concentration of antibody suspensions, their pH and incubation time, designed to optimize the immunocapture of bacteria. The perf…

Materials science[SDV]Life Sciences [q-bio]Clinical BiochemistryGalliumBiosensing Techniques02 engineering and technology010402 general chemistrymedicine.disease_cause01 natural sciencesArticleAntibodiesArsenicalsLimit of DetectionMonolayerEscherichia colimedicineRegenerationregenerable biosensorbacteria detectionThin filmElectrodesEscherichia coliDetection limitChromatography<i>Escherichia coli</i>self-assembled monolayersSelf-assembled monolayerGeneral Medicinepiezoelectric ZnO thin film021001 nanoscience & nanotechnologyGaAs membranebulk acoustic waves0104 chemical sciencesSoundMembraneElectrodeGoldZinc Oxide0210 nano-technologyBiosensorTP248.13-248.65BiotechnologyBiosensors
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Specificity and Sensitivity Characterization of a Gallium Arsenide Resonant Bio-Sensor

2018

International audience; The characterization of the performances of a Gallium Arsenide (GaAs) based biosensor, in terms of sensitivity and specificity, is reported. The design of the sensor consists in a resonant membrane fabricated in GaAs crystal that operates at shear modes of bulk acoustic waves generated by lateral field excitation. The transducer element was fabricated by using typical clean room microfabrication techniques. The backside of the membrane is functionalized by a self-assembled monolayer (SAM) of alkanethiols to immobilize bio-receptors, which will allow the specific capture of the analyte of interest. The theoretical sensitivity of the sensor had been determined by model…

[SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph]AnalyteMaterials sciencebusiness.industry010401 analytical chemistry02 engineering and technology021001 nanoscience & nanotechnology01 natural sciences0104 chemical sciencesGallium arsenide[SPI.MAT]Engineering Sciences [physics]/Materialschemistry.chemical_compoundTransducerchemistryMonolayerOptoelectronicsSensitivity (control systems)[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics0210 nano-technologybusinessBiosensorExcitationMicrofabrication
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Deposition and characterization of ZnO thin films on GaAs and Pt/GaAs substrates

2020

Abstract This work reports the deposition and characterization of piezoelectric ZnO thin films on semi-insulating GaAs substrates for the fabrication of bulk acoustic waves sensors. ZnO films are deposited at 350 °C and low deposition rate using reactive radio frequency magnetron sputtering. The use of a Pt bottom electrode, between ZnO and GaAs, with and without Ti buffer layer, as well as the effect of the substrate crystallographic orientation are investigated. The characterization of the deposited films is performed to determine the optimal parameters for obtaining high-quality films and ZnO residual conductivity. ZnO films are textured along the c-axis for all GaAs cuts. The highest st…

Materials sciencebusiness.industry02 engineering and technologySubstrate (electronics)Conductivity010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciences0104 chemical sciencesResidual stressSurface roughnessOptoelectronicsGeneral Materials ScienceTexture (crystalline)Thin film0210 nano-technologybusinessLayer (electronics)Deposition (law)Materials Chemistry and Physics
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