The quantal hypothesis states that neurotransmitter is released in discrete packages, quanta, thought to represent the neurotransmitter content of individual vesicles. If true, then vesicle size should influence quantal size. Although chromaffin cells are generally thought to have a single population of secretory vesicles, our electron microscopy analysis suggested two populations as the size d...

Glucose oxidase (GOx) is an enzyme frequently used in glucose biosensors. As increased temperatures can enhance the performance of electrochemical sensors, we investigated impact temperature pulses on GOx that was drop-coated flattened Pt microwires. The wires were heated by alternating current. sensitivity towards and stability amperometry. An up to 22-fold increase observed. Spatially resolve...

We evaluated a new analyzer that measures lactate in undiluted whole blood by direct (or undiluted) amperometry [Nova Stat Profile 7 Analyzer (SP7); Nova Biomedical, Waltham, MA] by comparing it with two other analyzers, one for measuring lactate in whole blood by indirect (or diluted) amperometry [Model 2300; Yellow Springs Instrument Co. (YSI), Yellow Springs, OH] and another for measuring la...

Using environmental cues for the prediction of future events is essential for survival. Such cue-outcome associations are thought to depend on mesolimbic circuitry involving the nucleus accumbens (NAc) and prefrontal cortex (PFC). Several studies have identified roles for both NAc and PFC in the expression of stable goal-directed behaviors, but much remains unknown about their roles during lear...

Cover picture: Schematic of amperometric detection of exocytosis at a neuroendocrine cell. iii To Mike and Julia iv v ABSTRACT Exocytosis is the universal basis for neuronal communication, allowing the controlled release of neurotransmitter molecules from the presynaptic cell. Exocytosis has been widely studied in many systems. However, the details of this vital process are not fully understood...

in this work poly eriochrome black t (ebt) was electrochemically synthesized on the glassy carbon electrode as electrode modifier. on the modified electrode, voltammetric behavior of isoniazid (inh) was investigated. the poly (ebt)-modified glassy carbon electrode has excellent electrocatalytic ability for the electrooxidation of isoniazid. this fact was appeared as a reduced overpotential of i...

metallic copper nanoparticles modified glassy carbon electrode is fabricated by reduction of cuso4 in the presence of cetyltrimethylammonium bromide (ctab) through potentiostatic method. as-prepared nanoparticles are characterized by scanning electron microscopy and electrochemical methods. copper oxide modified glassy carbon electrode (nano-cuo/mgce) is prepared using consecutive potential sca...

The effect of latrunculin A, an inhibitor of actin cross-linking, on exocytosis in PC12 cells was investigated with single cell amperometry. This analysis strongly suggests that the actin cytoskeleton might be involved in regulating exocytosis, especially by mediating the constriction of the pore. In an extended kiss-and-run release mode, actin could actually control the fraction of neurotransm...