This work describes the development of a dedicated, fully automated sequential-injection analysis (SIA) apparatus suitable for simultaneous electrogenerated chemiluminescence (ECL) and amperometric detection. The instrument is composed of a peristaltic pump, a multiposition selection valve, a home-made potentiostat, a thin-layer electrochemical/optical flow-through cell, and a light detector. C...

A method is described for the measurement of hydrogen in expired air, using an electrochemical detector. The apparatus is simple to use and sensitive. Its application is illustrated by studies of small bowel transit time made by measuring the time between oral ingestion of the unabsorbable carbohydrate lactulose and a rise in the concentration of hydrogen in expired air. In 20 control subjects ...

Pedagogy as a science of education must be epistemologically grounded on complex systems, being a contemporary scientific paradigm that explains the processes of teaching and learning based on a neural network that integrates electrochemical, biological, genetic, and social elements in a complex reality that is surrounded by uncertainty, indeterminism and emergences resulting from the constant ...

Bacteriorhodopsin protein (bR)-based systems are one of the simplest known biological energy converters. The robust chemical, thermal and electrochemical properties of bR have made it an attractive material for photoelectric devices. This study demonstrates the photoelectric response of a dry bR layer deposited on a nitrocellulose membrane with indium tin oxide (ITO) electrodes. Light-induced e...

To clarify the association between oxidative DNA damage and the neurotoxicity of arsenic, the formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) as an index of oxidative DNA damage in the brain was examined in mice fed with drinking water containing 1 or 2 ppm arsenic, using an HPLC-electrochemical detector and immunohistochemical method. 8-OHdG levels were significantly increased in the brain o...

Tyrosinase (TYR) was covalently immobilized onto amino-functionalized carbon felt (CF) surface via glutaraldehyde (GA). Prior to the TYR-immobilization, primary amino group was introduced to the CF surface by treatment with 3-aminopropyltriethoxysilane (APTES). The resulting TYR-immobilized CF was used as a working electrode unit of an electrochemical flow-through detector for monoand di-phenol...

Since the isolation of artemisinin 32 years ago, it has been analyzed by different chromatographic techniques. This work compared the analysis of artemisinin from crude plant samples by GC with flame ionization detection (GC-FID) and HPLC with evaporative light scattering detector (HPLC-ELSD). Data is also presented indicating that GC is suitable for the quantification of two of artemisinin pre...

AIM To study the changes of monoamines in ventrolatoral periaqueductal gray of rat brain before and after electroacupuncture (EA) analgesia (EAA) was enhanced by fenfluramine (Fen), a 5-hydroxytryptamine (5-HT) releaser. METHODS Monoamines were collected by in vivo microdialysis and measured by HPLC connected with electrochemical detector. RESULTS The level of norepinephrine (Nor) after EA ...

the importance of nanotechnology in medical technologies, especially biomedical diagnostics, is indubitable. by taking advantages of nanomaterials, many medical diagnostics methods have been developed so far, including electrochemical nanobiosensors. they have been used for quantification of different clinical biomarkers for detecting, screening, or follow up a disease. micrornas (mirnas) are o...

Here we provide an extremely simple, rapid, direct, sensitive and specific method to quantify for the first time intracellular GSH in human prostate cancer cells (DU145) and human lung adenocarcinoma cells (A549) using an electrochemical detector coupled to a high performance liquid chromatograph (HPLC-ECD). GSH determination in cancer cells are importance because GSH has been involved in the d...