Refine
Year of publication
Institute
Language
- English (68) (remove)
Document Type
- Article (62)
- Conference Proceeding (6)
Keywords
- biosensors (3)
- acetoin (2)
- capacitive field-effect sensor (2)
- tobacco mosaic virus (TMV) (2)
- Bacillus atrophaeus (1)
- Bioabsorbable (1)
- Calorimetric gas sensor (1)
- Capacitive field-effect sensor (1)
- DNA hybridization (1)
- Dehydrogenase (1)
- Diaphorase (1)
- Enzymatic biosensor (1)
- Hydrogen peroxide (1)
- LAPS (1)
- Label-free detection (1)
- O2 plasma (1)
- Plant virus (1)
- Polyimide (1)
- Polylactide acid (1)
- Resistive temperature detector (1)
- Silk fibroin (1)
- Simultaneous determination (1)
- Sterilisation process (1)
- TMV adsorption (1)
- Ta₂O₅ gate (1)
- Tobacco mosaic virus (1)
- Tobacco mosaic virus (TMV) (1)
- Zeta potential (1)
- acetoin reductase (1)
- actuator-sensor system (1)
- alcoholic beverages (1)
- amperometric biosensors (1)
- annealing (1)
- bi-enzyme biosensor (1)
- biocompatible (1)
- biocompatible materials (1)
- biodegradabl (1)
- biodegradable electronic devices (1)
- calorimetric gas sensor;hydrogen peroxide;wireless sensor system (1)
- capacitive field-effect biosensor (1)
- capacitive field-effect sensors (1)
- carbon electrodes (1)
- electrolyte-insulator semiconductor sensor (EIS) (1)
- encapsulation materials (1)
- endospores (1)
- enzyme immobilization (1)
- enzyme kinetics (1)
- enzyme-logic gate (1)
- fibroin (1)
- field-effect sensor (1)
- glucose (1)
- hydroxylation (1)
- immobilization (1)
- lable-free detection (1)
- light-addressable electrode (1)
- light-addressable potentiometric sensor (1)
- microfluidics (1)
- organosilanes (1)
- penicillinase (1)
- plant virus detection (1)
- silanization (1)
- surface functionalization (1)
- urease (1)
Field-effect-based electrolyte-insulator-semiconductor (EIS) sensors were modified with a bilayer of positively charged weak polyelectrolyte (poly(allylamine hydrochloride) (PAH)) and probe single-stranded DNA (ssDNA) and are used for the detection of complementary single-stranded target DNA (cDNA) in different test solutions. The sensing mechanism is based on the detection of the intrinsic molecular charge of target cDNA molecules after the hybridization event between cDNA and immobilized probe ssDNA. The test solutions contain synthetic cDNA oligonucleotides (with a sequence of tuberculosis mycobacteria genome) or PCR-amplified DNA (which origins from a template DNA strand that has been extracted from Mycobacterium avium paratuberculosis-spiked human sputum samples), respectively. Sensor responses up to 41 mV have been measured for the test solutions with DNA, while only small signals of ∼5 mV were detected for solutions without DNA. The lower detection limit of the EIS sensors was ∼0.3 nM, and the sensitivity was ∼7.2 mV/decade. Fluorescence experiments using SybrGreen I fluorescence dye support the electrochemical results.
In this work, a cell-based biosensor to evaluate the sterilization efficacy of hydrogen peroxide vapor sterilization processes is characterized. The transducer of the biosensor is based on interdigitated gold electrodes fabricated on an inert glass substrate. Impedance spectroscopy is applied to evaluate the sensor behavior and the alteration of test microorganisms due to the sterilization process. These alterations are related to changes in relative permittivity and electrical conductivity of the bacterial spores. Sensor measurements are conducted with and without bacterial spores (Bacillus atrophaeus), as well as after an industrial sterilization protocol. Equivalent two-dimensional numerical models based on finite element method of the periodic finger structures of the interdigitated gold electrodes are designed and validated using COMSOL® Multiphysics software by the application of known dielectric properties. The validated models are used to compute the electrical properties at different sensor states (blank, loaded with spores, and after sterilization). As a final result, we will derive and tabulate the frequency-dependent electrical parameters of the spore layer using a novel model that combines experimental data with numerical optimization techniques.
The feasibility of light-addressed detection and manipulation of pH gradients inside an electrochemical microfluidic cell was studied. Local pH changes, induced by a light-addressable electrode (LAE), were detected using a light-addressable potentiometric sensor (LAPS) with different measurement modes representing an actuator-sensor system. Biosensor functionality was examined depending on locally induced pH gradients with the help of the model enzyme penicillinase, which had been immobilized in the microfluidic channel. The surface morphology of the LAE and enzyme-functionalized LAPS was studied by scanning electron microscopy. Furthermore, the penicillin sensitivity of the LAPS inside the microfluidic channel was determined with regard to the analyte’s pH influence on the enzymatic reaction rate. In a final experiment, the LAE-controlled pH inhibition of the enzyme activity was monitored by the LAPS.