Synthesis of vanadium oxide nanoplates for electrochemical detection of amaranth in food samples

Amaranth dye is an organic compound largely used in the food and beverage industries with potential toxicity effects on humans. In this paper, a new electrochemical sensor used for the determination of amaranth in foods was reported, where a kind of V2O5 nanoplates (V2O5-NPs) was employed as electrode modifying materials. The V2O5 nanoplates modified electrode enhanced its electrochemical signal obviously in the determination of amaranth in foods and exhibited a wider linear response ranging from 0.1-270.0 µM with a low detection limit of 0.04 ± 0.001 µM (3Sb/m). This work offers a new route in developing new electrochemical sensors for the determination of colorant additives and other hazardous components in foods

PVC-membrane potentiometric sensors based on a recently synthesized Schiff base for Fe(III) ion

A potentiometric iron sensor based on the use 3-(2-diethylamino-ethylimino)-1,3-dihydro-indol-2-one (DEDIO) as an ionophore in poly(vinyl chloride) (PVC) matrix, is reported. The plasticized membrane sensor exhibits a Nernstian response for Fe(III) ions over a wide concentration range (2.0 × 10-6 - 5.0 × 10-2 M) with a super Nernstian slope of 26(plus or minus 1) mV per decade. It has a fast response time of less than 12 s and can be used for ten weeks without any considerable divergences in its potentials the electrode can be used in the pH range 4.5-8.0. The proposed sensor shows fairly good discriminating ability towards Fe(III) ion in comparison with a large number of alkali, alkaline earth, transition and heavy metal ions. The sensor was used as indicator electrode in potentiometric titration of Fe(III) ions vs. EDTA.DOI: http://dx.doi.org/10.4314/bcse.v26i1.

Comparison of the essential oil content and composition of the spathe, buds and pollen of <i>Phoenix dactylifera</i>

<div><p>Several medicinal applications have been reported for different components of date palm. The inflorescence of the male date tree is composed of spathe that surrounds many buds containing pollen. In this study, a comparison between the content and composition of the essential oils obtained from these three components of an inflorescence was made. After obtaining each oil using hydro-distillation method, the oil yield was measured as the weight ratio of the oil to the distilled sample (w/w %) and the chemical composition of the oil was determined by gas chromatography–mass spectrometry analysis. It was observed that the pollen possessed the most oil content (1.47%) composed of 68.04% oleic acid, whereas the content of this fatty acid in the spathe and bud oils was found to be less than 0.05% and 5.65%, respectively. Spathe oil was dominated by 3,4-dimethoxytoluene (52.90%) while the main constituent of the bud oil was <i>trans</i>-caryophyllene (44.20%).</p></div

Synthesis of cellulose acetate nanofibers and its application in the release of some drugs

Objective(s): The purpose of this study was to compare novel sandwich-structured nanofibrous membranes, and coaxial and usual methods, to provide sustained-release delivery of morphine for drug delivery. In this work, synthesis ofnanofibrous cellulose acetate (NFC) was carried out by electrospinning. Methods: A weighed amount of cellulose acetate (CA) powder was dissolved in 3:1 v/v acetone/dimethylformamide (DMF) to obtain a CA solution at a concentration of 8 to16% w/v. Acetaminophen or morphine-loaded CA solutions were prepared by dissolving CA powder and Acetaminophen (A) or morphine in the weight ratio of 5:1, in an acetone/DMF mixture. Under optimum condition, they were electrospun into sandwich structured membranes with the coaxial method and cellulose acetate as the surface layer and cellulose acetate/drugs as the core. Results: Characterization of the radius of fiber is shown as 52.9 ± 0.1nm with scanning electron microscopy (SEM). The full range drug release profiles of nanofibers are shown as 80.7% of the contained drug in 8h. The drug release from nanofiber was controlled through a typical Fickian diffusion mechanism from the cellulose acetate matrix by a release exponent value of 0.24 for conventional nanofiber, 0.35 for coaxial nanofiber and 0.40 (less than 0.45) for sandwich nanofibers. Conclusions: All the cellulose acetate nanofibers showed that they could release large amounts of drugs in vitro for more than one day. However, among these three methods, the best one is a sandwich method because its release is slower than that of the other methods

Dispersive liquid-liquid microextraction for the simultaneous separation of trace amounts of zinc and cadmium ions in water samples prior to flame atomic absorption spectrometry determination

In the proposed method, carbon tetrachloride and ethanol were used as extraction and dispersive solvents. Several factors that may be affected on the extraction process, such as extraction solvent, disperser solvent, the volume of extraction and disperser solvent, pH of the aqueous solution and extraction time were optimized. Under the optimal conditions, linearity was maintained between 1.0 ng mL-1 to 1.5 mg mL-1 for zinc and 1.0 ng mL-1 to 0.4 mg mL-1 for cadmium. The proposed method has been applied for determination of trace amount of zinc and cadmium in standard and water samples with satisfactory results