scholarly journals Simultaneous Determination of Iron and Cobalt using Spectrophotometry after Catanionic Mixed Micellar Cloud Point Extraction Procedure

2020 ◽  
Vol 36 (6) ◽  
pp. 1168-1172
Author(s):  
Ravi Kumar Kakitha ◽  
Shyamala Pulipaka ◽  
Deva Hari Puranam
Keyword(s):  
Mixed Micelles ◽  
Sea Water ◽  
Tap Water ◽  
Sodium Dodecyl ◽  
Extraction Procedure ◽  
Maximum Efficiency ◽  
Hcl Concentration ◽  
Cationic And Anionic Surfactants ◽  
Preconcentration Method

A new preconcentration method which utilises a mixture of cationic and anionic surfactants for separation and spectrophotometric determination of iron and cobalt simultaneously has been developed. The metal ions, iron and cobalt were complexed with thiocyante. The hydrophobic complexes of iron and cobalt were then extracted into catanionic mixed micelles of cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS). Different parameters like concentration of HCl, concentration of thiocyanate, concentrations of the surfactants (CTAB and SDS), equilibration temperature and time were studied to get maximum efficiency. The linear ranges of Fe3+ and Co2+ were found to be 0.139 – 0.838 μg mL–1 and 5.89 – 35.4 μg mL–1, respectively the detection limits obtained were 1.54 ng mL–1 and 6.18 ng mL–1. The developed procedure has been employed for the retrieval of Fe3+ and Co2+ in water samples successfully (tap water and sea water). 98 – 107% recoveries were obtained.

Cold-trap preconcentration method for the determination of mercury in sea water and in other natural materials

1974 ◽  
Vol 46 (13) ◽  
pp. 1882-1885 ◽  
Author(s):  
William F. Fitzgerald ◽  
W. Berry. Lyons ◽  
Carlton D. Hunt
Keyword(s):  
Sea Water ◽  
Cold Trap ◽  
Natural Materials ◽  
Preconcentration Method

The Effect of Fertilisation on the Permeability to Water and on Certain Other Properties of the Surface of the Egg of Psammechinus Miliaris

1932 ◽  
Vol 9 (1) ◽  
pp. 69-92
Author(s):  
A. D. HOBSON
Keyword(s):  
Sea Water ◽  
Tap Water ◽  
Surrounding Medium ◽  
Volume Changes ◽  
Single Experiment ◽  
Stage Of Development ◽  
Maximum Value ◽  
Hypertonic Solutions ◽  
Psammechinus Miliaris

1. A photographic method is described for recording volume changes in seaurchin eggs. 2. The behaviour of the eggs of Psammechinus miliaris, both before and at various intervals after fertilisation, in relation to osmotic changes in the surrounding medium have been investigated. 3. The rate of entrance of water from hypotonic sea water into the egg increases immediately after fertilisation takes place, rises to a first maximum at about 3 min. after fertilisation. It then falls to a comparatively low value at about 5 min. after fertilisation. After this the rate increases steadily to a maximum value which is reached about 35 min. after fertilisation. It remains steady until just before cleavage when, in the single experiment continued until this stage of development, it decreased very markedly. 4. The action of hypertonic solutions on the egg has been examined. Several types of plasmolysis occur and are characteristic of different stages in the development of the egg after fertilisation. The type of plasmolysis is determined principally by the physical properties of the egg surface. The plasmolysis method is of little use in this material for the determination of relative permeability to dissolved substances at different stages of development. 5. The rate of cytolysis in tap water has been investigated and its relation to permeability of the egg surface to water is considered. There is a susceptible period followed by one of resistance during the first 5-10 min. after fertilisation. The rate of cytolysis is conditioned, not only by the rate of entrance of water but also by the degree to which the cell surface will withstand stretching. The latter may be a significant factor. 6. The rate of Zytolysis in extremely hypertonic solutions of sea water + NaCl has been examined. It increases to a maximum at about 5-10 min. after fertilisation. Thereafter it decreases. Cytolysis in the unfertilised egg and just after fertilisation is a sudden process. Later it becomes more and more gradual and progresses slowly from the surface to the interior of the egg. The relation between the rate of cytolysis and permeability is uncertain.

Sensitive Derivative Synchronous and Micellar Enhanced Ecofriendly Spectrofluorimetric Methods for the Determination of Atenolol, Diclofenac, and Triclosan in Drinking Tap Water

2020 ◽  
Author(s):  
Nardine Safwat ◽  
Maha F Abdel-Ghany ◽  
Miriam F Ayad
Keyword(s):  
Emerging Contaminants ◽  
Analytical Procedure ◽  
Solid Phase ◽  
Tap Water ◽  
Sodium Dodecyl ◽  
Linear Calibration ◽  
Enhanced Fluorescence ◽  
First Derivative ◽  
Spectrofluorimetric Method

Abstract Background Nowadays, emergence of unexpected contaminants in drinking water is a challenging environmental problem facing humanity. Objective Two eco-friendly spectrofluorimetric methods were proposed for the determination of three unexpected contaminants in drinking tap water. Methods The first method is first derivative synchronous spectrofluorimetric method which was developed for simultaneous determination of atenolol (ATN) and diclofenac (DCF) without prior separation at Δλ = 70 nm and at Δλ = 80 nm for ATN and DCF, respectively. The second method was based on using sodium dodecyl sulfate (SDS) as fluorescent enhancer of triclosan (TCS) native fluorescence. TCS exhibits enhanced fluorescence at λ emission = 600 nm upon excitation at λ excitation = 299.4 nm. Solid phase extraction was carried out in both methods. Results Linear calibration curves were obtained in concentration range of (4–3000 ng/mL) for ATN and (4–2000 ng/mL) for DCF, by measuring first derivative signal of fluorescence at 300 nm and 375.2 nm, respectively. TCS exhibits linear range (0.1–1 ng/mL) at 600 nm. Mean percentage recoveries were 101.04 ± 0.571, 99.66 ± 1.443, and 99.73 ± 0.566 for ATN, DCF, and TCS, respectively. Conclusions Validation of both methods were performed according to the International Conference on Harmonization guidelines. Results obtained were statistically compared with published methods and no significant differences were found. The proposed methods’ greenness is evaluated using analytical Eco-scale and Green Analytical Procedure Index. A greenness comparison with previously published methods has been performed. Highlights Both methods were found to be eco-friendly and were successfully applied for the determination of the emerging contaminants in drinking tap water.

scholarly journals Accurate determination of pesticides, hormones and endocrine disruptor compounds in complex environmental samples using matrix dilution and matrix matching with dispersive liquid–liquid microextraction

2018 ◽  
Vol 90 (11) ◽  
pp. 1703-1711 ◽  
Author(s):  
Dotse Selali Chormey ◽  
Merve Fırat ◽  
Çağdaş Büyükpınar ◽  
Fatih Erulaş ◽  
Okan Tarık Komesli ◽  
...  
Keyword(s):  
Environmental Samples ◽  
Sea Water ◽  
Tap Water ◽  
Accurate Determination ◽  
Deionized Water ◽  
Complex Nature ◽  
Calibration Standards ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

AbstractQuantitative determination of contaminants in environmental samples is usually hampered by low analyte recovery which results from the complex nature of the sample matrix. This study presents the application of a developed dispersive liquid–liquid microextraction method for the determination of 12 analytes in environmental samples including sea water, fresh water (lake, well and tap water), brackish water and soil samples. Matrix matched standards were used to compensate for the low analyte recovery recorded by the conventional calibration method. The effect of matrix dilution on analyte recovery was also tested. All matrix matched and matrix diluted spiked recoveries were done concurrently with calibration standards prepared in deionized water. Percent recoveries recorded for the analytes according to deionized water calibration standards ranged between 66 and 137%. Matrix matching and matrix dilution yielded close to 100% recovery results, but the later lowered the detection limit according to the dilution factor.

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