The development of biosensors for detection and identification of DNA sequences by hybridization may reduce assay time and allow direct quantitation of the target. This article describes the use of impedance spectroscopy technique for digoxigeninthiol-labeled ssDNA probe immobilization, anti-digoxigenin binding and targeted DNA hybridization. The analysis of the impedance spectra in terms of eq...

Many electrochemical/bioelectrochemical systems are intrinsically nonstationary and are affected by time-dependent phenomena. The requirement of stationarity in the classical version of impedance spectroscopy appears to be in conflict with the essential properties of the object, therefore a post-experimental mathematical/analytical procedure is necessary for the reconstruction of the 'true' imp...

− The paper presents a new method of impedance measurement for impedance spectroscopy. The method is based on square pulse excitation and digital signal processing of sampled current and voltage response. The main innovation in the proposed method is sampling moments optimisation adequate to the object under test. The method was tested by Matlab simulations and results are not worse than in pre...

The paper presents a fast impedance spectroscopy method for objects with very high impedance |Zx|≥1GΩ modeled by multi-element two-terminal RC networks. The method is based on analysis of the object response in the time domain after square pulse excitation. The object impedance spectrum was obtained using continuous Fourier transform. Simulation tests were performed for different excitation pul...

We carried out degradation analysis of a blue phosphorescent organic light emitting diode by both impedance spectroscopy and transient electroluminescence (EL) spectroscopy. The number of semicircles observed in the Cole-Cole plot of the modulus became three to two after the device was operated for 567 hours. Considering the effective layer thickness of the initial and degraded devices did not ...

Different types of charge storage mechanisms at unmodified graphite vs. glassy carbon electrodes in acid sulphate supporting solution containing potassium hexacyanoferrate (II) redox active electrolyte, have been revealed by electrochemical impedance spectroscopy and supported by cyclic voltammetry experiments. Reversible charge transfer of Fe(CN)6 redox reaction detected by assessment of CVs o...

Carbon nanotubes have generated much research interest and potential applications due to their unique properties such as their high tensile strength, high thermal conductivity, and unique semiconductor properties. Vertically-aligned carbon nanotubes (VA-CNTs) have been used in applications for electrochemical systems in energy storage systems and desalination systems. Typical methods of charact...

In order to develop a robust biosensor based on quartz crystal microbalance technique for antigen detection, a control of the steps of the surface functionalization has been performed by impedance spectroscopy. The gold electrode is functionalized with the self-assembled monolayer technique. The high insulating properties of the acidic thiol monolayer has been characterized with cyclic voltamme...

We present a label-free biosensor based on electrochemical impedance spectroscopy for the detection of proinflammatory cytokine Tumor Necrosis Factor (TNF-α). Secretion of TNF-α has been correlated to the onset of various diseases including rheumatoid arthritis, Crohn’s disease etc. Gold electrodes were patterned on a silicon substrate and self assembled monolayer of dithiobis-succinimidyl prop...

Local Electrochemical Impedance Spectroscopy (LEIS) is an emerging discipline in the field of electrochemical research. It is based on the widely accepted Electrochemical Impedance Spectroscopy (EIS) technique, a powerful method to determine reaction mechanisms on macroscopic electrodes. When however the electrode represents a heterogeneous behavior, local information is indispensable. This pro...