Determination of Gold in Various Environment Samples by Flame Atomic Absorption Spectrometry Using Dispersive Liquid–Liquid Microextraction Sampling

A new dispersive liquid–liquid microextraction separation/preconcentration procedure as a rapid sample-preparation technique is proposed for detection of ultra trace amounts of Au(III) in various media by flame atomic absorption spectrometry using 1,5-diphenyl-1,3,5-pentanetrione as chelating agent. Carbon tetrachloride and methanol were used as extraction and dispersive solvents, respectively. Various parameters that affect the extraction efficiency such as pH, centrifugation rate and time, chelating agent concentration and sampling volume on the recovery of Au(III) were investigated. Under optimum conditions, the enhancement factor of 750, relative standard deviation of 2.7 % and calibration graphs obtained in the concentration range of 0.04–5.6 μg L−1 for gold were obtained. The limit of detection was 1.1 ng L−1. The accuracy of the method was performed by analysis of the certified reference material (CDN-PGMS-10). The developed method was applied successfully to the determination of gold in the catalytic converter, anode slime, ore and seawater samples. The results show that dispersive liquid–liquid microextraction procedure is sensitive, rapid, simple and safe for the separation/preconcentration of gold from complex sample media

Dispersive Liquid-Liquid Microextraction of Bismuth in Various Samples and Determination by Flame Atomic Absorption Spectrometry

A dispersive liquid-liquid microextraction method for the determination of bismuth in various samples by flame atomic absorption spectrometry is described. In this method, crystal violet was used as counter positive ion for BiCl4- complex ion, chloroform as extraction solvent, and ethanol as disperser solvent. The analytical parameters that may affect the extraction efficiency like acidity of sample, type and amount of extraction and disperser solvents, amount of ligand, and extraction time were studied in detail. The effect of interfering ions on the analyte recovery was also investigated. The calibration graph was linear in the range of 0.040–1.00 mg L−1 with detection limit of 4.0 μg L−1 (n=13). The precision as relative standard deviation was 3% (n=11, 0.20 mg L−1) and the enrichment factor was 74. The developed method was applied successfully for the determination of bismuth in various water, pharmaceutical, and cosmetic samples and the certified reference material (TMDA-64 lake water)

Determination of Arsenic(III) and Total Arsenic at Trace Levels in Baby Food Samples via a New Functionalized Magnetic Graphane Oxide Nanocomposite

Baby food safety is an essential issue in health policy. For this reason, a simple, cheap, and fast analytical procedure to developed arsenic(III) and total arsenic determination in baby food samples using functionalized magnetic graphane oxide nanocomposite. A new nanocomposite anchored of tiopronin (TSH) magnetic graphane oxide (GO-PG4@Fe3O4-TSH) was first synthesized/characterized and used as an adsorbent to determine arsenic(III) and total arsenic for baby food samples. Arsenic(III) was directly determined on GO-PG4@Fe3O4-TSH nanocomposite at pH 4.5. The determination of total arsenic used KI and L( +) ascorbic acid solution as reducing reagents. The parameters influential on arsenic(III) determination in the baby food samples including the sample's pH, adsorption time, amount of GO-PG4@Fe3O4-TSH, eluent type, sample volume, reducing reagent type and amount, and also foreign ion effect were investigated. The GO-PG4@Fe3O4-TSH carrying As(III) could easily be separated from baby food samples via applying an external magnetic field. The detection limit for arsenic(III) was found as 0.11 mu g L-1, while the limit of quantification values was computed as 0.37 mu g L-1. The precision of results, expressed as relative standard deviation, was always lower than 1.6% at 1 mg L-1 As(III) levels. The accuracy of this method was confirmed by analysis of certified reference material. The method was successively applied to determine arsenic(III) and total arsenic in baby food samples

Highly selective adsorption of cadmium ions by water-dispersible magnetic thioglycolic acid/graphene oxide composites

A new selective and fast procedure based on magnetic dispersive solid-phase extraction and zeta potential analysis is proposed for the determination of Cd (II) in some food samples. In the developed method, novel magnetic nanoparticles modified with thioglycolic acid were synthesized/characterized and also applied for quantitative determination of trace amounts of Cd (II) in food samples. The prepared nanoparticles were characterized via infrared spectroscopy, electron microscopy and adsorption-desorption experiments. These magnetic nanocomposites carrying Cd (II) could be easily separated from real samples simply by applying an external magnetic field; no filtration or centrifugation was necessary. Several parameters affecting the analytical performance, such as sample pH, amounts of nanocomposite sample, desorption solution volumes and coexisting ions, were investigated in detail. The detection limit of the method was 0.1 mu g l(-1) while the relative standard deviation was 1.2% for a Cd (II) concentration of 0.5 mg l(-1). The proposed method was successfully applied to food sample analysis and standard reference material samples with satisfactory results, and excellent recoveries were obtained in the range 9599% even when the matrix, such as sea water, was complex

Application of a new functionalized magnetic graphane oxide for aluminum determination at trace levels in honey samples by the zetasizer system

Heavy metals in honey are of interest not only for quality control, but also as an environmental indicator. In the present work, we developed a new selective and rapid magnetic dispersive solid-phase extraction (MDSPE) method for the separation/determination of Al(III) in honey samples by the zetasizer system. The synthesis of a new nanocomposite comprised of aminosilanized magnetic graphane oxide (GO/Fe3O4/APS)-coated 2-hydroxy-5-methyl-1,3-benzene-dicarboxaldehyde (HB) (GO/Fe3O4/APS@HB) is synthesized and characterized in for the first time the present work. The parameters influential on the determination of Al(III) including the pH of the sample, sorption time, amount of nanocomposite, eluent type, concentration, volume, and elution time, were investigated and optimized. These magnetic nanocomposites carrying Al(III) could be easily separated from honey samples simply by applying an external magnetic field; no filtration/centrifugation was necessary. Moreover, GO/Fe3O4/APS@HB demonstrates selectivity toward Al(III). Under the optimum conditions, the detection limits (DL) of the method for Al(III) was found to be (3 s) 0.13 mu g L--1,L- the preconcentration factor was calculated as 65, and the relative standard deviation was obtained as <= 2% for n = 11. The method was performed for the determination of Al(III) in some honey samples. The proposed techniques show satisfactory sensitivity, selectivity, detection limits and standard deviation for Al(III) determination in a honey sample. The method is suitable for the analysis of honey samples, which are challenging to analyze using other spectroscopy techniques

Effect of heavy metals and sialic acid in multiple sclerosis

Bu çalışmanın amacı multipl sklerozlu hastalarda ağır metaller, sialik asit ve diğer çevresel faktörlerin etkisini araştırmaktır. Çalışmaya 52 multipl skleroz hastası ve 41 sağlıklı gönüllü kontrol grubu olarak dahil edildi. Sırasıyla, sialik asit ve ağır metallerin belirlenmesi için açlık tükürük ve idrar örnekleri alındı. MS hastalarında, kontrol grubuna göre, Al (p &lt;0.001), As (p &lt;0.001), Ba (p &lt;0.05), Cd (p &lt;0.005), Cs (p &lt;0.001), Cu (p &lt;0.05), Mn (p &lt;0.05), Ni (p &lt;0.001), Pb (p &lt;0.001), Rb (p &lt;0.05), Sr (p &lt;0.05)&nbsp; ve&nbsp; sialik asit düzeyleri (p &lt;0.001) anlamlı yüksek, Ti (p &lt;0.05) ve Fe (p &lt;0.05) değerleri ise düşük bulundu.&nbsp; Siyalik asit, ağır metal seviyeleri, sebze tüketimi, bağırsak alışkanlıkları ve multipl skleroz grubu arasında anlamlı ilişki vardı. Bu çalışmada, yüksek siyalik asit ve ağır metal seviyelerinin, daha az sebze tüketiminin ve kötü bağırsak alışkanlıklarının multipl skleroz için risk faktörü olduğu bulunmuştur.Anahtar kelimeler: Sebze tüketimi, ağır metaller, multipl skleroz, sialik asit, kötü bağırsak alışkanlıkları.&nbsp;The aim of this study is to investigate the effect of heavy metals, sialic acid and other environmental factors in patients with multiple sclerosis. Fifty-two multiple sclerosis patients and 41 healthy volunteers as the control group were included in the study. Fasting saliva and urine samples were taken to determine sialic acid and heavy metals respectively.The levels of Ag (p&lt;0.001), Al (p&lt;0.001), As (p&lt;0.001), Ba (p&lt;0.05), Cd (p&lt;0.005), Cs (p&lt;0.001), Cu (p&lt;0.05), Mn (p&lt;0.05), Ni (p&lt;0.001), Pb (p&lt;0.001), Rb (p&lt;0.05), Sr (p&lt;0.05), and sialic acid levels (p&lt;0.001) were found significantly higher, Ti (p&lt;0.05) and Fe (p&lt;0.05) lower in MS patients compared to the control group. There was a significant relationship between sialic acid, heavy metals levels, vegetable consumption, bowel habits and multiple sclerosis group. In this study, it was found that high levels of sialic acid and heavy metals, less vegetable consumption and bad bowel habits were risk factors for multiple sclerosis.Key words: Vegetable consumption, heavy metals, multiple sclerosis, sialic acid, bad intestinal habits.</p