Trace Amounts Of Phosphate Research Articles

Development of Biomass-Based Anion Exchanger for the Removal of Trace Concentration of Phosphate from Water

Aluminum loaded saponified Mango Waste i.e. Al (III)–SMW adsorbent, which functions as anion exchanger, was developed by loading Al (III) onto lime treated Mango waste biomass. The characterization of adsorbent was done by an Energy Dispersive X-ray (EDX) spectroscopy and chemical analysis techniques. Elemental analysis showed an exchange of Ca (II) or K (I) from SMW with Al (III) during loading reaction via cation exchange mechanism. Phosphate adsorption is strongly pH-dependent and maximum adsorption occurs at pH around 7– 9. The maximum uptake capacity of Al (III)–SMW for phosphate was found to be 3.28 mg/g from the Langmuir isotherm model. The residual concentration of phosphate was sharply decreased by increasing the amount of Al (III)–SMW and reached less than 0.07 mg/L (from 9.7 mg/L) with the use of only 6 g/L of Al (III)–SMW whereas higher than 7 g/L successfully removed 100% of phosphate from water. The adsorbed phosphate was successfully desorbed and the adsorbent was regenerated using dilute alkali solution. Therefore, the Al (III)–SMW adsorbent investigated in this research work is expected to be a potential material for the treatment of water polluted with a trace amount of phosphate from aqueous solution.

Synthesis of Cellulose Functionalized with Polyallylamine and Its Application to On-line Collection/Concentration and Determination of Phosphate by ICP/AES

A novel cellulose-based resin functionalized with polyallylamine was synthesized. It was applied to the collection of phosphate in environmental water samples, followed by concentration determination using an inductively coupled plasma-atomic emission spectrometer (ICP/AES). The synthesized resin, cellulose-glycidylmethacrylate-polyallylamine (CGP), showed good adsorption behavior toward trace amounts of phosphate over a wide pH range. The adsorbed-analyte can be easily eluted using 0.5 M hydrochloric acid; its recoveries was found to be 80 - 100%. The CGP resin synthesized was packed in a mini-column, which was then installed in a computer-controlled auto-pretreatment system for on-line collection/concentration and determination of trace phosphate by ICP/AES. The limit of detection for phosphate was found to be 0.6 µg P l(-1). The sample volumes were only 5 ml and the total analysis time was about 4 min. The developed method with CGP resin was successfully applied to the determination of phosphate in river water and tap water samples with satisfactory results. The recovery test showed that common matrices that may exist in environmental waters did not interfere with the determination of phosphate.

Determination of phosphate as aggregates of ion associates by light-scattering detection and application to flow injection

Trace amounts of phosphate were determined by detecting the light-scattering intensity with a spectrofluorimeter. The ion associate of molybdophosphate with a chloro derivative of Malachite Green (Cl-MG) or Rhodamine B (RB) formed aggregates in an acidic solution before precipitating. The formation rates of molybdophosphate and its ion associate were rapid, but that of the aggregate was relatively slow. To stabilize the aggregates and to prevent their precipitation in an aqueous medium, poly(vinyl alcohol) solution was added after the formation of the ion associate. The light-scattering intensity of the ion associate with Cl-MG, which did not emit fluorescence, could be detected. The intensities were obtained at the same wavelength of emission as that of excitation: 460 nm for Cl-MG and 460 and 580 nm for RB. The diameter of the aggregate was determined to be mainly 650 nm by using a laser light-scattering detector. The number of ion associates in the aggregate was roughly estimated to be 4.3 × 107. The calibration graph was rectilinear up to 10–6 mol dm–3 phosphate in the batchwise method. The method was applied to flow injection, where the calibration graph was rectilinear from 2 × 10–7 to 1 × 10–6 mol dm–3 and the detection limit was 6 × 10–8 mol dm–3. The average peak height for 8.0 × 10–7 mol dm–3 phosphate was 9.6 cm and the RSD of five measurements was 1.1%. The sample throughput was 15 h–1. Interferences from bulky and hydrophobic anions were slight.

Chapter 22 Nonradioactive Method for ATPase Assays

Publisher Summary There is change in orthophosphate concentration by colorimetry. Nonradioactive ATPase assays follow the change. This happens after quenching an ATP-hydrolyzing reaction at regular time intervals and converting phosphate into a phosphomolybdate complex. A very sensitive method of this kind determines the quantity of phosphomolybdate as a complex with malachite green. The method described in this chapter, developed by Kodama and colleagues, is sensitive enough to measure 0.2–15 μM phosphate, a concentration range that other colorimetric methods cannot measure. The method is simple and reliable; the citric acid added after initiation of the coloring reaction removes excess molybdate and thereby greatly reduces the nonenzymatic hydrolysis of ATP catalyzed by molybdate. Because of its high sensitivity, this assay was used for measuring the ATPase activities of myosin and kinesin on a single microscope coverslip in in vitro motility assays. It has been used to measure the ATPase activities in Chlamydomonas inner-arm dynein fractions in which only small amounts of proteins are available. This chapter discusses the solutions and the procedure involved. There are also suggestions on precautions needed; like, because commercial sodium citrate is often contaminated with trace amounts of phosphate, it has been advised to prepare it from citric acid and NaOH, rather than purchase it. Use of tubes that have been washed with detergent and distilled water often results in a large scatter in the data, so disposable test tubes cannot be used, to be used are test tubes that have been rinsed with 0.5 N HCI and DDW. With higher concentrations of ATP, the time for the coloring reaction needs to be constant.

Gel-phase absorptiometry of phosphate with molybdate and Malachite Green and its application to flow analysis

The ion associate formed by the reaction of molybdophosphate with Malachite Green was adsorbed on Sephadex LH-20, a hydroxypropyl derivative of a Sephadex dextran gel. Direct absorptiometric measurements of the ion associate in the gel phase were carried out after either batch or on-line concentration of the species. For the batch method, the coloured gel beads, on which the ion associate was adsorbed, were packed into a specially designed 5-mm cell; the attenuance at 627 and 750 nm was measured and the difference was used for the determination of trace amounts of phosphate. For the flow method, after mixing the sample with the molybdate-Malachite Green solution, the coloured species was concentrated on-line on to the gel packed in a flow-through cell; the increase in the attenuance at 627 nm was used for the determination of phosphate. As both methods are highly sensitive, phosphate can easily be determined in water samples at µg dm–3 levels or lower.

Surface mannan from Glomerella cingulata.

A specific layer at the outermost surface of mycelia of Glomerella cingulata G 4-1-4 was observed. The substance isolated from this layer was a polysaccharide ([α]20D +82.6°C) composed of o-mannose (97.6%), protein (2.0%) and a trace amount of phosphate. A high proportion of 3, 4-di-O-methylmannose (38mol%) was found on methylation analysis. Digestion of this mannan with a bacterial α-D-mannosidase released 78% of the D-mannose. In addition, the results of acetolysis, partial acid hydrolysis, and 1H- and 13C-NMR spectroscopy showed that the G. cingulata G 4-1-4 mannan has a backbone joined by α-l, 6-linkages, and α-1, 2- and 1, 3-linked mannose residues are attached to the C-2 position of the main chain segment, giving it a highly branched structure. Although G. cingulata G 4-1-4 mannan has the above properties, its basic structure appears to be similar to that of baker's yeast mannan.

Determination of trace amounts of phosphate in water samples by ion-exchange resin thin-layer spectrophotometry

A simple but highly sensitive method for determining trace amounts of phosphate in water has been developed. The method involves concentrating molybdenum blue in a thin layer prepared from a finely divided anion-exchange resin and measurement of the absorbance of the coloured layer. The dependence of the absorbance on the concentration of sulphuric acid and ammonium molybdate resulting from the procedure for producing molybdenum blue was reduced by adding gelatin to the sample solution. The calibration graph deviated slightly from linearity and the relative standard deviation was 1.95%(n= 4) for 0.5 µg of phosphate. This method was applied to the determination of trace amounts of phosphate in several water samples.

Structure of the cell wall proteogalactomannan from Neurospora crassa. I. Purification of the proteoheteroglycan and characterization of alkali-labile oligosaccharides.

Proteoheteroglycan (PHG) was prepared from Neurospora crassa cells by extraction with hot water followed by cetyltrimethylammoniumbromide fractionation. The polymer was purified by DEAE-cellulose chromatography followed by gel filtrations. The PHG was fractionated into five subfractions containing carbohydrate (65-88%), protein (19-36%), and a trace amount of phosphate (0.3-1.9%). The sugar compositions of the fractions were similar to each other (D-mannose, 47-60%, D-galactose, 35-50%, D-glucose, 2-5%) while the fractions showed significant heterogeneity in molecular size. Mild alkali treatment of the PHG in the presence of sodium borohydride yielded three kinds of reduced oligosaccharides. Structural studies using a methylation-GC-MS method, and proton and carbon NMR indicated that the tetrasaccharide fragment is beta-D-Galf(1-5)-beta-D-Galf(1-2)-alpha-D-Manp(1-2)man nitol, the trisaccharide is beta-D-Galf(1-2)-alpha-D-Manp(1-2)mannitol, and the disaccharide is alpha-D-Manp(1-2)mannitol.

Isolation and Characterization of the Starch from Four‐O'Clock Flower (Mirabilis Jalapa L.) Seed

ABSTRACTStarch was isolated from four‐o'clock flower (Mirabilis jalapa L.) seed by an alkaline process and selected physicochemical properties was determined. The nearly spherical starch granules were approximately 1.5–3.0 μm in diameter. The starch had a pasting temperature of 72.5°C, and an iodine affinity of 3.6%. The Bra‐bender viscoamylogram and the swelling pattern indicated the starch underwent restricted swelling. The starch contained only trace amounts of phosphate. Solubility in dimethyl sulfoxide was low, but after being treated with bacterial alpha‐amylase, the solubility was high. The degree of syneresis of the pasted starch during storage was high and freeze‐thaw stability was low. The properties of this isolated small‐granule starch differed from other such starches reported in the literature.

Spectrophotometric determination of phosphate in river waters with molybdate and malachite green

On the basis of the coloration formed with molybdate and malachite green in aqueous solution, trace amounts of phosphate were determined. The molar absorptivity was 7.8 × 104 l mol–1 cm–1 at 650 nm. The absorbance of the reagent blank was about 0.02, and its relative standard deviation was less than 10%. The recommended concentration range of phosphorus was 0.1–5 µg and the limit of detection was 0.01 µg of phosphorus. The sample solution was acidified with sulphuric acid and heated in a water-bath above 90 °C for 40 min, and subsequently it was coloured with molybdate and malachite green. The colour was stabilised by adding poly(vinyl alcohol). The method was applied to the determination of parts per billion (109) amounts of phosphorus in river and tap waters; the relative standard deviation was less than 4% and the recovery was 95–101%.

ChemInform Abstract: DUAL WAVELENGTH SPECTROPHOTOMETRIC DETERMINATION OF TRACE AMOUNTS OF PHOSPHATE IN THE PRESENCE OF LARGE AMOUNTS OF SILICATE USING MOLYBDENUM BLUE

A method is described for the determination of trace amounts of phosphate in the presence of large amounts of silicate. It is based on the difference in the absorption spectra of molybdenum blues formed from phosphate and silicate using a dual-wavelength spectrophotometer. The difference in absorbances at 797.3 nm and 825.0 nm is proportional to phosphate concentration over the range 1.60×10−7 to 7.00×10−5 M (1 M=1 mol dm−3).

Extraction-spectrophotometric determination of trace amount of phosphate by the use of a mixed solvent

Extraction-spectrophotometric determination of trace amount of phosphate by the use of a mixed solvent

Determination of trace amounts of phosphate in water extracts of soils

Abstract Two methods are described for determining water‐soluble phosphate in the range 0.5 to 10 μg P/l, using solvent extraction for the concentration of molybdenum blue. The manual shaking method had a precision of 0.02 μg P/l; the continuous extraction method, a precision of 0.05 μg P/l. The methods have been found suitable for measuring phosphate in water extracts of soils.

THE ACUTE EFFECTS OF INTRAVENOUS INFUSION OF PARATHYROID HORMONE ON URINE, PLASMA AND SALIVA IN THE SHEEP

Following an intravenous loading injection of 75 U.S.P. Units of Para-Thor-Mone (Eli Lilly and Co), seven conscious, non-pregnant, non-lactating Merino ewes were infused with a maintenance dose of the hormone at a rate of 4-75 U.S.P. units/min for 2 hr. The classical hypercalcaemia and hypophosphataemia of the non-ruminant was observed, but the hypercalcaemi- was only small. Plasma potassium concentration decreases, while there were no changes in plasma sodium, chloride or mangesium. The classical phosphaturic effect of the hormone was not observed, only trace amounts of phosphate being exreted throughout the experiment. Urinary excretion of calcium and magnesium decreased, urine flow and urinary excretion of sodium, potassium, chloride, bicarbonate and urine pH increased. Glomerular filtration rate was unaffected, but renal plasma flow increased. The concentration and secretion rate of salivary phosphate increased markedly. Changes in the other important salivary electrolytes (sodium, potassium, chloride, bicarbonate and hydrogen ion) also occurred, but it was difficult to separate primary from secondary effects of the hormone. Saliva flow rate increased transiently following hormone injection, but the effect was not sustained by the maintenance infusion.