Thoroughly clean and rinse all glassware with the supplied BWB Technologies deionised distilled water to ensure that it is clean and free of extractable sodium and potassium. Glassware should be acid cleaned and rinsed thoroughly in deionised double distilled water prior to use to avoid contamination from extractable metals under test.
There are many different ways to express concentration of a solution. Molarity (M): Molarity is probably the most commonly used unit of concentration. It is the number of moles of solute per litre of solution (not necessarily the same as the volume of solvent). The SI unit of molarity is mol/dm3.
This method reduces or removes potential interference from sodium, potassium and phosphates normally present in serum and urine by diluting the samples with a diluent containing ethylenediaminetetraacetic acid (EDTA).
The use of lithium carbonate for the treatment of bipolar disorders and depression is well established. However, for the treatment to be effective, it must be managed closely, to ensure the dose is maintained within the normal therapeutic range.
The calcium content of aqueous solutions of deoxyribonucleic acid (DNA) and deoxyribonucleoprotein (DNP) cannot assayed directly because of interference effects. An acid extraction procedure enabled direct measurements of calcium in DNA and DNP, or a standard addition technique was used at higher concentrations.
This method uses a suspension of ground plant material to directly measure the potassium concentration. It eliminates the usual steps of ashing and subsequent dissolution of the resulting ash. The method was compared to alternative methods such as chemical analysis and spectrophotometric methods. Collaborative studies using a range of samples gave a mean of 1.74% potassium by this extraction technique as compared to 1.75% by alternative methods. The standard deviation of an analysis in the two different sample...
A number of methods have been reported for the measurement of calcium in biological materials by flame photometry or titration. This method employs trichloroacetic acid (TCA) to precipitate the proteins and has been found to be adequate to extract all of the calcium from tissue samples. Sodium, potassium and phosphate caused no significant interference and calcium concentration in the range of 0 to 2 µg/ml is readily determined.
BS EN 14108 and EN14109 (2003) Reference Method for Measurement of Trace Elements in Biodiesel 1,2. These methods are adapted from methods for the determination of sodium and potassium in fatty-acid methyl ester samples. The sample is diluted with an organic solvent (xylene, cyclohexane or petroleum ether) plus a stabiliser. These European Standards specify a method for the determination of potassium of equal to or greater than 0.5 mg/kg and sodium level equal to or greater than 1 mg/kg. This method is...
The most important ions which naturally occur in plant tissues are sodium, potassium, calcium, magnesium, nitrate, sulphate and phosphate. A sample of 5 g of oven-dried plant material contains on average, 25 mg calcium, 9 mg magnesium, 80 mg potassium and 3 mg sodium. The recommended method for the measurement of calcium is to precipitate the calcium as an oxalate, the precipitate is then dissolved and measurement taken from the resulting solution. Sodium and potassium may be measured directly following an...
Commercial cereals vary considerably in composition, both in their formulation and the ingredients added to enrich these products. Sodium is the predominant cation in breakfast cereals, at levels reaching 8mg/g. Potassium and calcium also vary, particularly in wheat-based products and those enriched with milk products or calcium salts.
Wine is of particular interest nutritionally because it is typically low in sodium and relatively high in potassium. Sodium is the predominant cation in breakfast cereals, at levels reaching 8mg/g. Potassium and calcium also vary, particularly in wheat-based products and those enriched with milk products or calcium salts.
Bread contributes about one-sixth of daily salt intake and is used to improve flavour and texture. The amount of sodium in bread can differ significantly, depending upon brand and type of grain used, ranging from 592mg/100g to 748mg/100g. The level of sodium in bread is primarily due to the amount of salt added to the dough during manufacture. The amount of potassium is determined by the type of flour and the washing and bleaching operations during cereal processing. Bread does not make a significant contributio...
Several different techniques can be used for sample digestion and extraction of sodium and/or potassium: oven ashing, perchloric acid ashing, extraction by boiling and acidification with HNO3 as well as extraction by homogenisation in 2% trichloroacetic acid (TCA).
In most cases, it was found that flame photometry was well suited for the determination of sodium, potassium and calcium in fresh fruits, using the wet ashing technique as given below. There are significant differences in the composition between different varieties of the same fruit, although these differences are not usually considered to be nutritionally significant.
This technique allows use of aqueous standards for calibration rather than relatively unstable organometallic standards and harmful solvents for the extraction. Microemulsions are thermodynamically stable systems composed of water, oil and surfactant. In some cases, an alcohol is added as a co-surfactant.
Sodium chloride is an essential ingredient of all processed foods;it is needed to enhance flavour and increase shelf life. In many processed foods, additional sodium is added as a flavour enhancer; potassium and calcium are also naturally present but not normally used as processing additives.
This method for the measurement of sodium and potassium in silicate rocks uses a borate fusion technique.The sample is fused with a suitable fusion agent such as boric acid (H3BO3) and lithium carbonate (Li2CO3) and the ground product is dissolved in dilute citric acid.The presence of other metals such as aluminium, calcium, iron, magnesium and silicon should not interfere with the measurement of sodium or potassium using this method.
The effect of potential interference from other constituents of sea water was studied, including sodium, chloride and potassium. It was found that pre-concentration of the sea water was not necessary prior to analysis. A filtration of the sample was only necessary if sample contained suspended material.