A flow injection method is reported for the determination of ascorbic acid based on amperometric detection, using a cobalt(II) phthalocyanine (CoPc) modified graphite-epoxy electrode. The amperometric respons was evaluated with regard to pH, ionic strength of the electrolyte, flow rate of the carrier solution, injected sample volume and conditioning time of the electrode. The limit of detec...

UNLABELLED The in vitro viability, chemotaxis, and labeling stability of leukocytes labeled using (99m)Tc-exametazime stabilized with methylene blue were evaluated and compared with those obtained using nonstabilized (99m)Tc-exametazime. METHODS Two identical leukocyte populations, from 30 healthy donors, were labeled simultaneously using freshly prepared and 2-h-old stabilized (99m)Tc-examet...

an agricultural waste and eco-friendly biosorbent i.e. rice husk has been used as a cheap adsorbentfor the removal of methylene blue dye from aqueous solutions. the physical properties of the developedadsorbent were characterized using ftir. the study was realized using batch experiments. the effectsof contact time, ph, initial dye concentration, biosorbent dose and temperature were investigate...

Chromium contamination in the area of the Radomka river basin in Poland has lead to significant environmental problems. Therefore, chromium redox transformations were investigated in the aquatic environment under conditions as close to natural as possible at intermediate pH and in the presence of original bottom sediment and dissolved oxygen. Reduction of Cr(VI) in the Radomka river water occur...

A detailed study of the oxidation of L-ascorbic acid by dioxygen and nitrite in water at pH 5.8 and 7.0, catalyzed by the octasulfophenyltetrapyrazinoporphyrazine complex of cobalt(II), was carried out using conventional spectrophotometric, low-temperature and high-pressure stopped-flow techniques. The Co(II) complex activates L-ascorbic acid through an intramolecular one-electron oxidation ste...

The photoelectrochemical determination of ascorbic acid (AA) was studied based on the photochemical reduction of methylene blue (MB) in 0.1 M phosphate buffer (pH 7.0). MB was used as a redox mediator for the modification of a carbon paste electrode (CPE) due to its facile reducible-oxidizible behaviour. Muscovite, which has a layered structure, was found to be a good and stable supporting mate...

The in vitro viability, chemotaxis, and labeling stability of leukocytes labeled using 99mTc-exametazime stabilized with methylene blue were evaluated and compared with those obtained using nonstabilized 99mTc-exametazime. Methods: Two identical leukocyte populations, from 30 healthy donors, were labeled simultaneously using freshly prepared and 2-h-old stabilized 99mTc-exametazime. The followi...

Dry matter, organic acids, ascorbic acid, minerals (nitrogen, phosphorus, potassium, calcium, magnesium, sodium) and polyphenolic profile of a number of non-traditional fruit species and their genotypes, namely blue honeysuckle (Lonicera spp.), Saskatoon berry (Amelanchier alnifolia), black mulberry (Morus nigra), Tomentosa cherry (Prunus tomentosa Thunb.) and jostaberry (Ribes nigrum x Grossul...