The surface interrogation mode of scanning electrochemical microscopy (SI-SECM) was used for the detection and quantification of adsorbed hydroxyl radical ˙OH((ads)) generated photoelectrochemically at the surface of a nanostructured TiO(2) substrate electrode. In this transient technique, a SECM tip is used to generate in situ a titrant from a reversible redox pair that reacts with the adsorbe...

A physic-mathematical model has been developed that is suitable for biosensors incorporating membranes and bisubstrate enzymes. The set of equations regarding the transport of reactants across the membrane, the bisubstrate enzymatic reaction, back diffusion of reactants and reaction products, are written down and simultaneously solved and transient response of the electrode is determined as...

A novel electrochemical sensor was proposed for the determination of amitriptyline based on the copper oxide (CuO) nanoparticles modified graphite screen-printed electrode. CuO nanoparticles were used to enhance the surface area of the electrode and then improve the sensitivity of the electrochemical sensor. Amitriptyline electrochemical response characteristics of the modified electrode in a p...

A novel electrochemical sensor was proposed for the determination of amitriptyline based on the copper oxide (CuO) nanoparticles modified graphite screen-printed electrode. CuO nanoparticles were used to enhance the surface area of the electrode and then improve the sensitivity of the electrochemical sensor. Amitriptyline electrochemical response characteristics of the modified electrode in a p...

A device for continuous differential impedance analysis of single cells held by a hydrodynamic cell trapping is presented. Measurements are accomplished by recording the current from two closely-situated electrode pairs, one empty (reference) and one containing a cell. We demonstrate time-dependent measurement of single cell impedance produced in response to dynamic chemical perturbations. Firs...

A cellulose-based glucose oxidase membrane was prepared on a glassy carbon (GC) electrode. The current response of the electrode to glucose was measured by applying a potential of 1.0 V vs. Ag/AgCl on the base GC and was proportional to the concentration of glucose up to 1 mM. The long-term stability of the electrode was examined by measuring the daily glucose response. Over four months, the re...

carbon paste electrode was modified by disodium 2,4-diamino-7-methylbenzo[g] pteridine-5,10-dioxide to fabricate a sensor for potentiometric determination of vanadyl ion (vo2+) in aqueous medium. the new ligand was synthesized in three steps with high yield. the optimal composition of the carbon paste was made of graphite powder (64.5%), ionophore (16.6%), paraffin oil (17.8%), and sodium tetra...

Here, we report on the use of electrochemical methods for the detection of volatiles fatty acids (VFAs), namely acetic acid. We used tetra-tert-butyl phthalocyanine (PcH₂-tBu) as the sensing material and investigated its electroanalytical properties by means of cyclic voltammetry (CV) and square wave voltammetry (SWV). To realize the electrochemical sensing system, the PcH₂-tBu has been dropcas...