Determination of CMC of Polysorbate 20 in Aqueous Solution by Surface Tension Method

Abstract The good quality of several manufactured components frequently depends on solidliquid interactions existing during processing. Nowadays, the research in material engineering focuses also on modern, automatic measurement methods of joining process properties, i.a. wetting force and surface tension, which allows for quantitative determination of above mentioned parameters. In the paper, the brazes’ dynamic properties in high-temperatures’ measurement methodology and the stand for automatic determination of braze’s properties, constructed and implmented within the research grant nr KBN N N519 441 839 - An integrated platform for automatic measurement of wettability and surface tension of solders at high temperatures, are widely described

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Surface active agents. Determination of surface tension

10.3403/03164352u ◽

2015 ◽

Keyword(s):

Surface Tension ◽

Surface Active Agents ◽

Surface Active

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Plastics/rubber. Polymer dispersions and rubber latices (natural and synthetic). Determination of surface tension

10.3403/30382561 ◽

2020 ◽

Keyword(s):

Surface Tension ◽

Polymer Dispersions ◽

Natural And Synthetic

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Application of Silica Nanoparticles in the Determination of Herbicides in Environmental Water Samples Using Liquid Chromatography-Mass Spectroscopy

Current Nanoscience ◽

10.2174/1573413716666191224113231 ◽

2020 ◽

Vol 16 (5) ◽

pp. 748-756

Author(s):

Mir Waqas Alam ◽

Tentu Nageswara Rao ◽

Yarasani Prashanthi ◽

Vourse Sridhar ◽

Adil Alshoaibi ◽

...

Keyword(s):

Aqueous Solution ◽

Liquid Chromatography ◽

Silica Nanoparticles ◽

Solid Phase ◽

Silica Nanoparticle ◽

Environmental Water ◽

Phase Extraction ◽

Functionalized Nanoparticles ◽

Supporting Material

Background: Herbicides are very beneficial in the crop yield with the aid of controlling weeds within the agriculture, but several herbicides are chronic in soil. Objective: In this study, nanoparticles and the packages of synthesized novel silica nanoparticles were studied for the preconcentration of herbicides. Methods: These nanoparticles prepared by the Stöber mechanism were purified and functionalized. Nanoparticles thus prepared successfully were used as supporting material for the preconcentration of residues of herbicides in the water. Results: Preconcentration was achieved by preparing the silica-based solid-phase-extraction cartridges. Nanoparticles used for this purpose were within the range of 50-250 nm. An SPE cartridge was prepared by packing 200 mg of silica nanoparticle in the empty cartridge of diameter 5.5 cm and length 0.6 cm in between PTFE frits. Aqueous solutions of 0.1 μg/ml of herbicides were prepared separately, and 10 ml of the solution was passed through the cartridge at the rate of 0.2 ml/min. After passing 10 ml volume of the aqueous solution, residues adsorbed on the cartridge were eluted using 2 ml of acetonitrile. The eluate was injected to determine the herbicide residue adsorbed on the SPE cartridge. Conclusion: In the study, it was found that greater than 90% of the herbicide residues were trapped on silica nanoparticle-based SPE cartridge. An analytical method was developed for the simultaneous determination of these herbicides. The residues were quantified by LC-MS/MS with ESI mode.

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Enzymatic colorimetry of lecithin and sphingomyelin in aqueous solution.

Clinical Chemistry ◽

10.1093/clinchem/29.8.1513 ◽

1983 ◽

Vol 29 (8) ◽

pp. 1513-1517 ◽

Cited By ~ 10

Author(s):

M W McGowan ◽

J D Artiss ◽

B Zak

Keyword(s):

Aqueous Solution ◽

Hydrogen Peroxide ◽

Amniotic Fluid ◽

Enzymatic Reaction ◽

Detergent Solution ◽

Enzymatic Determination ◽

Red Color ◽

Hydrolysis Of ◽

Zwitterionic Detergent

Abstract A procedure for the enzymatic determination of lecithin and sphingomyelin in aqueous solution is described. The phospholipids are first dissolved in chloroform:methanol (2:1 by vol), the solvent is evaporated, and the residue is redissolved in an aqueous zwitterionic detergent solution. The enzymatic reaction sequences of both assays involve hydrolysis of the phospholipids to produce choline, which is then oxidized to betaine, thus generating hydrogen peroxide. The hydrogen peroxide is subsequently utilized in the enzymatic coupling of 4-aminoantipyrine and sodium 2-hydroxy-3,5-dichlorobenzenesulfonate, an intensely red color being formed. The presence of a non-reacting phospholipid enhances the hydrolysis of the reacting phospholipid. Thus we added lecithin to the sphingomyelin standards and sphingomyelin to the lecithin standards. This precise procedure may be applicable to determination of lecithin and sphingomyelin in amniotic fluid.

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