12 research outputs found
Detection of Adrenaline Based on Substrate Recycling Amplification
An amperometric enzyme biosensor has been applied for the detection of adrenaline. The adrenaline biosensor has been prepared by modification of an oxygen electrode with the enzyme laccase that operates at a broad pH range between pH 3.5 to pH 8. The enzyme molecules were immobilized via cross-linking with glutaraldehyde. The sensitivity of the developed adrenaline biosensor in different pH buffer solutions has been studied
Evaluation of field-effect sensors modified with carbon nanotubes for urea detection: Properties and signal stability.
Aufbau einer digitalen Infrastruktur für Forschungsdaten im außeruniversitären Bereich mit dem Anwendungsfall der PICOS App
(2R,3R)-Butan-2,3-diol-Dehydrogenase aus Bacillus clausii DSM 8716T - Ein vielversprechender Biokatalysator für die Synthese chiraler a-Hydroxyketone/Diole sowie zur Biosensorentwicklung
Acetoin reductase‐modified field‐effect sensor for the detection of acetoin in beer samples
(R,R)-Butane-2,3diol dehydrogenase from Bacillus clausii DSM 8716T - a versatile biocatalyst
Dehydrogenation of 2,3-Butanediol to 3-Hydroxybutanone Over CuZnAl Catalysts: Effect of Lithium Cation as Promoter
Piezophototronic gated optofluidic logic computations empowering intrinsic reconfigurable switches
Incorporating a Hybrid Urease-Carbon Nanotubes Sensitive Nanofilm on Capacitive Field-Effect Sensors for Urea Detection
The ideal combination among biomolecules and nanomaterials is the key for reaching biosensing units with high sensitivity. The challenge, however, is to find out a stable and sensitive film architecture that can be incorporated on the sensor’s surface. In this paper, we report on the benefits of incorporating a layer-by-layer (LbL) nanofilm of polyamidoamine (PAMAM) dendrimer and carbon nanotubes (CNTs) on capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensors for detecting urea. Three sensor arrangements were studied in order to investigate the adequate film architecture, involving the LbL film with the enzyme urease: (i) urease immobilized directly onto a bare EIS [EIS-urease] sensor; (ii) urease atop the LbL film over the EIS [EIS-(PAMAM/CNT)-urease] sensor; and (iii) urease sandwiched between the LbL film and another CNT layer [EIS-(PAMAM/CNT)-urease-CNT]. The surface morphology of all three urea-based EIS biosensors was investigated by atomic force microscopy (AFM), while the biosensing abilities were studied by means of capacitance–voltage (C/V) and dynamic constant-capacitance (ConCap) measureaments at urea concentrations ranging from 0.1 mM to 100 mM. The EIS-urease and EIS-(PAMAM/CNT)-urease sensors showed similar sensitivity (∼18 mV/decade) and a nonregular signal behavior as the urea concentration increased. On the other hand, the EIS-(PAMAM/CNT)-urease-CNT sensor exhibited a superior output signal performance and higher sensitivity of about 33 mV/decade. The presence of the additional CNT layer was decisive to achieve a urea based EIS sensor with enhanced properties. Such sensitive architecture demonstrates that the incorporation of an adequate hybrid enzyme-nanofilm as sensing unit opens new prospects for biosensing applications using the field-effect sensor platform