scholarly journals Silver Nanoparticles Functionalized with Sodium Mercaptoethane Sulfonate to Remove Copper from Water by the Formation of a Micellar Phase

Separations ◽  
2021 ◽  
Vol 8 (8) ◽  
pp. 108
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca Garratón ◽  
María del Carmen García-Onsurbe ◽  
Antonio Soto-Meca
Keyword(s):  
Silver Nanoparticles ◽  
Water Samples ◽  
Essential Element ◽  
Aqueous Samples ◽  
Total Removal ◽  
Experimental Conditions ◽  
Micellar Phase ◽  
High Concentrations ◽  
Triton X ◽  
Total Elimination

This work presents a novel procedure for the removal of Cu2+ from water, an essential element in human nutrition considered toxic in high concentrations, based on a microextraction technique involving the formation of a micellar phase. To achieve the total elimination of copper from aqueous samples, a Cu2+-complexing reagent based on silver nanoparticles functionalized with sodium mercaptoethane sulfonate (AgNPs@MESNa) was used. The complex formed by Cu2+ and the reagent was extracted into a micellar microphase formed by Triton X-114, a harmless surfactant. Volumes of 200 µL of the 10−4 mol L−1 suspension of AgNPs@MESNa and 100 µL of a solution of Triton X-114 at 30% m/m were employed to successfully remove 10 mg L−1 of Cu from 20 mL of water samples. The time and temperature needed to achieve 100% microextraction efficiency were 10 min and 40 °C, respectively. The procedure is considered environmentally friendly due to the low volume of the extracting phase and the simple experimental conditions that achieve total removal of Cu2+ from water samples.

scholarly journals Electroanalytical Techniques for the Detection of Selenium as a Biologically and Environmentally Significant Analyte—A Short Review

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1768
Author(s):  
Miroslav Rievaj ◽  
Eva Culková ◽  
Damiána Šandorová ◽  
Zuzana Lukáčová-Chomisteková ◽  
Renata Bellová ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Essential Element ◽  
Analytical Techniques ◽  
High Sensitivity ◽  
Stripping Voltammetry ◽  
Short Review ◽  
Electroanalytical Methods ◽  
High Concentrations ◽  
Speed Of Analysis

This short review deals with the properties and significance of the determination of selenium, which is in trace amounts an essential element for animals and humans, but toxic at high concentrations. It may cause oxidative stress in cells, which leads to the chronic disease called selenosis. Several analytical techniques have been developed for its detection, but electroanalytical methods are advantageous due to simple sample preparation, speed of analysis and high sensitivity of measurements, especially in the case of stripping voltammetry very low detection limits even in picomoles per liter can be reached. A variety of working electrodes based on mercury, carbon, silver, platinum and gold materials were applied to the analysis of selenium in various samples. Only selenium in oxidation state + IV is electroactive therefore the most of voltammetric determinations are devoted to it. However, it is possible to detect also other forms of selenium by indirect electrochemistry approach.

scholarly journals Adsorption Studies on Magnetic Nanoparticles Functionalized with Silver to Remove Nitrates from Waters

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1757
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca ◽  
Antonio Soto-Meca ◽  
Miguel Ángel Martín-Pereira ◽  
María del Carmen García-Onsurbe
Keyword(s):  
Magnetic Nanoparticles ◽  
Nitrate Content ◽  
Adsorption Efficiency ◽  
Experimental Conditions ◽  
Dependent Behavior ◽  
Before And After ◽  
Naoh Solution ◽  
High Concentrations ◽  
Interference Studies

This paper presents a novel procedure for the treatment of contaminated water with high concentrations of nitrates, which are considered as one of the main causes of the eutrophication phenomena. For this purpose, magnetic nanoparticles functionalized with silver (Fe3O4@AgNPs) were synthesized and used as an adsorbent of nitrates. Experimental conditions, including the pH, adsorbent and adsorbate dose, temperature and contact time, were analyzed to obtain the highest adsorption efficiency for different concentration of nitrates in water. A maximum removal efficiency of 100% was reached for 2, 5, 10 and 50 mg/L of nitrate at pH = 5, room temperature, and 50, 100, 250 and 500 µL of Fe3O4@AgNPs, respectively. The characterization of the adsorbent, before and after adsorption, was performed by energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. Nitrates can be desorbed, and the adsorbent can be reused using 500 µL of NaOH solution 0.01 M, remaining unchanged for the first three cycles, and exhibiting 90% adsorption efficiency after three regenerations. A deep study on equilibrium isotherms reveals a pH-dependent behavior, characterized by Langmuir and Freundlich models at pH = 5 and pH = 1, respectively. Thermodynamic studies were consistent with physicochemical adsorption for all experiments but showed a change from endothermic to exothermic behavior as the temperature increases. Interference studies of other ions commonly present in water were carried out, enabling this procedure as very selective for nitrate ions. In addition, the method was applied to real samples of seawater, showing its ability to eliminate the total nitrate content in eutrophized waters.

scholarly journals Spatial Variation of Water Chemistry in Aries River Catchment Western Romania

2021 ◽  
Vol 11 (14) ◽  
pp. 6592
Author(s):  
Ana Moldovan ◽  
Maria-Alexandra Hoaghia ◽  
Anamaria Iulia Török ◽  
Marius Roman ◽  
Ionut Cornel Mirea ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Water Quality ◽  
Water Chemistry ◽  
Water Samples ◽  
Mine Drainage ◽  
Pollution Indices ◽  
Mining Activities ◽  
River Catchment ◽  
High Concentrations ◽  
The Impact

This study aims to investigate the quality and vulnerability of surface water (Aries River catchment) in order to identify the impact of past mining activities. For this purpose, the pollution and water quality indices, Piper and Durov plots, as well vulnerability modeling maps were used. The obtained results indicate that the water samples were contaminated with As, Fe, Mn, Pb and have relatively high concentrations of SO42−, HCO3−, TDS, Ca, K, Mg and high values for the electrical conductivity. Possible sources of the high content of chemicals could be the natural processes or the inputs of the mine drainage. Generally, according to the pollution indices, which were correlated to high concentrations of heavy metals, especially with Pb, Fe and Mn, the water samples were characterized by heavy metals pollution. The water quality index classified the studied water samples into five different classes of quality, namely: unsuitable for drinking, poor, medium, good and excellent quality. Similarly, medium, high and very high vulnerability classes were observed. The Durov and Piper plots classified the waters into Mg-HCO3− and Ca-Cl− types. The past and present mining activities clearly change the water chemistry and alter the quality of the Aries River, with the water requiring specific treatments before use.

scholarly journals Determination of essential and non-essential element contents of drinking water and baby water for infant’s nutrition

2021 ◽  
Vol 44 (1) ◽  
pp. 194-202
Author(s):  
Funda Demir ◽  
Meral Yildirim Ozen ◽  
Emek Moroydor Derun
Keyword(s):  
Water Samples ◽  
Infant Nutrition ◽  
Tap Water ◽  
Essential Element ◽  
Essential Elements ◽  
Local Market ◽  
Drinking Waters ◽  
Significant Difference ◽  
Element Contents

Abstract In this study, essential (Ca, Cr, Cu, Fe, K, Mg, Na, P, Zn), and non-essential (Al, Ni, Pb) element contents of the drinking and baby water samples which are sold in the local market and tap water samples in Istanbul were examined. It was determined that elements of Cr, Cu, Fe, P, Zn, Al, and Ni were below detection limits in all water samples. Among the non-essential elements analyzed in water samples, Pb was the only detected element. At the same time, the percentages that meet the daily element requirements of infants were also calculated. As a result of the evaluations made, there is no significant difference in infant nutrition between baby waters and other drinking waters in terms of the element content.

scholarly journals Determination of cobalt in water samples by atomic absorption spectrometry after pre-concentration with a simple ionic liquid-based dispersive liquid-liquid micro-extraction methodology

2010 ◽  
Vol 8 (3) ◽  
pp. 617-625 ◽  
Author(s):  
Hossein Abdolmohammad-Zadeh ◽  
Elnaz Ebrahimzadeh
Keyword(s):  
Ionic Liquid ◽  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Water Samples ◽  
Limit Of Detection ◽  
Absorption Spectrometry ◽  
Experimental Conditions ◽  
Flame Atomic Absorption ◽  
Relative Standard

AbstractA rapid dispersive liquid-liquid micro-extraction (DLLME) methodology based on the application of 1-hexylpyridinium hexafluorophosphate [C6py][PF6] ionic liquid (IL) as an extractant solvent was applied for the pre-concentration of trace levels of cobalt prior to determination by flame atomic absorption spectrometry (FAAS). 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was employed as a chelator forming a Co-PMBP complex to extract cobalt ions from aqueous solution into the fine droplets of [C6py][PF6]. Some effective factors that influence the micro-extraction efficiency include the pH, the PMBP concentration, the amount of ionic liquid, the ionic strength, the temperature and the centrifugation time which were investigated and optimized. In the optimum experimental conditions, the limit of detection (3s) and the enrichment factor were 0.70 µg L−1 and 60, respectively. The relative standard deviation (RSD) for six replicate determinations of 50 µg L−1 Co was 2.36%. The calibration graph using the pre-concentration system was linear at levels 2–166 µg L−1 with a correlation coefficient of 0.9982. The applicability of the proposed method was evaluated by the determination of trace amounts of cobalt in several water samples.

scholarly journals Determination of ultra-trace levels of palladium in water samples by cloud point extraction and graphite furnace atomic absorption spectrometry

2021 ◽  
pp. 174751982110273
Author(s):  
Quan Han ◽  
Yanyan Huo ◽  
Xiaohui Yang ◽  
Xing Yao
Keyword(s):  
Water Samples ◽  
Cloud Point Extraction ◽  
Graphite Furnace ◽  
Chelating Agent ◽  
Absorption Spectrometry ◽  
Graphite Furnace Atomic Absorption ◽  
Ultra Trace ◽  
Triton X ◽  
Optimized Conditions

A highly sensitive method for the determination of ultra-trace levels of palladium in water samples by cloud point extraction and graphite furnace atomic absorption spectrometry is developed. The procedure is based on complexation of palladium with a laboratory-prepared novel chelating agent, 2-(5-bromo-4-methyl-2-pyridylazo)-5-dimethylaminoaniline (5-Br-4-CH3-PADMA) and subsequent micelle-mediated extraction of the product using the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) as an extracting agent. Analytical parameters affecting the separation and detection process, such as pH, concentration of the chelating agent and surfactant, equilibration temperature, and time are investigated. The optimized conditions are as follows: pH 6.0 HAc–NaAc buffer solution, 1 × 10−5 mol L−1 5-Br-4-CH3-PADMA, and 0.1% (w/v) Triton X-114. Under the optimized conditions, the calibration graph is linear in the range of 0.1–12 ng/mL, the detection limit is 0.05 ng/mL for palladium, and the relative standard deviation is 2.9% ( c = 1.0 ng/mL, n = 10). The enrichment factor, defined as the ratio of the aqueous solution volume to that of the surfactant-rich phase volume after dilution with HNO3–methanol solution, is 200. The proposed method is applied to the determination of palladium in water samples with satisfactory results.

scholarly journals Activation of human platelets by immune complexes prepared with cationized human IgG

Blood ◽  
1993 ◽  
Vol 82 (10) ◽  
pp. 3045-3051
Author(s):  
M Schattner ◽  
M Lazzari ◽  
AS Trevani ◽  
E Malchiodi ◽  
AC Kempfer ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Platelet Activation ◽  
Immune Complexes ◽  
Platelet Rich Plasma ◽  
Human Platelets ◽  
Human Igg ◽  
Experimental Conditions ◽  
Induce Platelet Aggregation ◽  
Soluble Immune Complexes ◽  
High Concentrations

The present study shows that the ability of soluble immune complexes (IC), prepared with human IgG and rabbit IgG antibodies against human IgG, to trigger platelet activation was markedly higher for IC prepared with cationized human IgG (catIC) compared with those prepared with untreated human IgG (cIC). CatIC induced platelet aggregation and adenosine triphosphate release in washed platelets (WP), gel-filtered platelets (GFP), or platelet-rich plasma (PRP) at physiologic concentrations of platelets (3 x 10(8)/mL) and at low concentrations of catIC (1 to 30 micrograms/mL). On the contrary, under similar experimental conditions, cIC did not induce aggregation in PRP, WP, or GFP. Low aggregation responses were only observed using high concentrations of both WP (9 x 10(8)/mL) and cIC (500 micrograms/mL). Interestingly, catIC were also able to induce platelet activation under nonaggregating conditions, as evidenced by P-selectin expression. Cationized human IgG alone did not induce platelet aggregation in PRP but triggered either WP or GFP aggregation. However, the concentration needed to induce these responses, was about eightfold higher than those required for catIC. The responses induced either by catIC or cationized human IgG were completely inhibited by treatment with heparin, dextran sulphate, EDTA, prostaglandin E1, or IV3, a monoclonal antibody against the receptor II for the Fc portion of IgG (Fc gamma RII). The data presented in this study suggest that IgG charge constitutes a critical property that conditions the ability of IC to trigger platelet activation.

scholarly journals Revealing the nanoparticles aspect ratio in the glass-metal nanocomposites irradiated with femtosecond laser

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
S. Chervinskii ◽  
R. Drevinskas ◽  
D. V. Karpov ◽  
M. Beresna ◽  
A. A. Lipovskii ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Aspect Ratio ◽  
Femtosecond Laser ◽  
Laser Fluence ◽  
Spherical Shape ◽  
Soda Lime ◽  
Prolate Spheroid ◽  
Soda Lime Glass ◽  
Experimental Conditions ◽  
Glass Metal

Abstract We studied a femtosecond laser shaping of silver nanoparticles embedded in soda-lime glass. Comparing experimental absorption spectra with the modeling based on Maxwell Garnett approximation modified for spheroidal inclusions, we obtained the mean aspect ratio of the re-shaped silver nanoparticles as a function of the laser fluence. We demonstrated that under our experimental conditions the spherical shape of silver nanoparticles changed to a prolate spheroid with the aspect ratio as high as 3.5 at the laser fluence of 0.6 J/cm2. The developed approach can be employed to control the anisotropy of the glass-metal composites.

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