A flow-injection method has been developed for the determination of total sulphite in wine samples. After hydrolysis of bound sulphite, sulphur dioxide is separated from the matrix by means of an in-line gas diffusion module. For detection indirect amperometry is used, with iodine as oxidizing reagent. The iodine can be generated in-line by merging and mixing iodate and iodide solutions, or alt...

In this report, alkanethiol self assembled monolayers (SAM) with two different chain lengths were used to immobilize the functionalizing enzyme (glucose oxidase) onto gold nanopillar modified electrodes and the electrochemical processes of these functionalized electrodes in glucose detection were investigated. First, the formation of these SAMs on the nanopillar modified electrodes was characte...

Under physiological conditions, astrocytes not only passively support and nourish adjacent neurons, but also actively modulate neuronal transmission by releasing "glial transmitters," such as glutamate, ATP, and D-serine. Unlike the case for neurons, the mechanisms by which glia release transmitters are essentially unknown. Here, by using electrochemical amperometry and frequency-modulated sing...

Amperometry is a widely used technique for monitoring the secretion of catecholamines (CA) by exocytosis. The use of carbon fibre microelectrodes allows the on-line recording of CA released from a single secretory vesicle. Amperometric signals are generated by oxidation of the quantally released CA close to the electrode tip. Each event of exocytosis is called a secretory spike. Here we describ...

Many spikes in amperometric records of exocytosis events initially exhibit a prespike feature, or foot, which represents a steady-state flux of neurotransmitter through a stable fusion pore spanning both the vesicle and plasma membranes and connecting the vesicle lumen to the extracellular fluid. Here, we present the first evidence indicating that vesicular volume before secretion is strongly c...

The present work demonstrates the fabrication and performance of an enzymatic glucose biosensor based on ZnO nanowires (NWs) deposited on a Au-coated polyester (PET) substrate. Electrodeposition of ZnO NWs on the conducting PET substrate was carried out at 70 degrees C in an aqueous electrolyte consisting of zinc nitrate mixed with potassium chloride. Glucose oxidase (GOx) was subsequently immo...

In this work we compare the microstructures of intermetallic compounds (IMCs) in electrochemically stripped solder joints created by two different soldering methods (vapor phase soldering (VPS), and selective laser soldering with a CO2 laser). After the selective removal of the Sn phase with amperometry, the microstructure and structural composition of the IMC can be revealed in a detailed way,...

Wound assessment is usually performed in hospitals or specialized labs. However, since patients spend most of their time at home, a remote real time wound monitoring would help providing a better care and improving the healing rate. This review describes the advances in sensors and biosensors for monitoring the concentration of C-reactive protein (CRP), temperature and pH in wounds. These three...