Simultaneous Enrichment-Separation of Metal Ions from Environmental Samples by Solid-Phase Extraction Using Double-Walled Carbon Nanotubes

A solid-phase extraction (SPE) method has been developed using a column filled with double-walled carbon nanotubes for the preconcentration-separation of Co(II), Cu(II), Ni(II), Pb(II), Fe(III), and Mn(II) ions. Experimental parameters, including pH of the solution, sample volume, flow rate of the sample solution and eluents, etc., were investigated. Quantitative recoveries for the anayte ions were obtained at pH 9.0 with 2 M HNO(3) eluent at a flow rate of 2 mL/min. The influences of matrix ions were also investigated. The preconcentration factor was 100. Addition and recovery experiments for analyte ions in real water samples gave good results. The validity of the presented SPE method was tested by analysis of HR-1 Humber River Sediment certified reference material for each element

Solid-phase extraction of heavy metal ions on bucky tubes disc in natural water and herbal plant samples

A preconcentration-separation procedure has been established based on solid-phase extraction of Fe(III) and Pb(II) on bucky tubes (BTs) disc. Fe(III) and Pb(II) ions were quantitatively recovered at pH 6. The influences of the analytical parameters like sample volume, flow rates on the recoveries of analytes on BT disc were investigated. The effects of co-existing ions on the recoveries were also studied. The detection limits for iron and lead were found 1.6 and 4.9 mu g L (-aEuro parts per thousand 1), respectively. The validation of the presented method was checked by the analysis of TMDA-51.3 fortified water certified reference material. The presented procedure was successfully applied to the separation-preconcentration and determination of iron and lead content of some natural water and herbal plant samples from Kayseri, Turkey

Determination of Traces of Iron and Lead in Food and Water Samples After Preconcentration on Multiwalled Carbon Nanotubes

A new method using multiwalled carbon nanotubes as an SPE adsorbent was developed for the sensitive determination of trace iron and lead prior to flame atomic absorption spectrometry analysis. Iron and lead as 2,9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline chelates were adsorbed quantitatively on multiwalled carbon nanotubes at a pH of 6.0 and easily eluted with 10 mL 1 M HNO3. The influences of matrix ions were also examined. The LOD values for iron and lead were calculated as 1.3 and 2.9 mu g/L, respectively. Validation of the presented procedure was performed by the analysis of TMDA 54.4 fortified lake water and HR-1 Humber River sediment certified reference materials. The method was successfully applied to the determination of trace iron and lead in real environmental samples, and excellent results were achieved

Speciation of chromium by the combination of dispersive liquid-liquid microextraction and microsample injection flame atomic absorption spectrometry

A microextraction procedure was established for the speciation of total Cr, Cr(III), and Cr(VI). Sudan blue II was used as a ligand for speciation works. Some factors affecting the recoveries of chromium species, including type of extraction and dispersive solvents, pH, ligand amount, extraction time, and matrix ions, were examined. Optimum values for the dispersive liquid-liquid microextraction method were pH 6, LOD 0.34 mu g L-1, and preconcentration factor 400. Chromium(III) was quantitatively recovered under optimal conditions, while the recovery of chromium(VI) was below 10%. The relative standard deviation for Cr(III) determinations for the 10-replicate measurement of 0.3 mu g mL(-1) Cr(III) was 6.2%. The accuracy was verified using BCR-144R Sewage Sludge, IAEA 336 Lichen, and TMDA 25.3 certified water for trace elements. The procedure was applied to speciation of chromium in water samples. Total chromium was determined in various wheat, bread, and hair samples

Ultrasound assisted ionic liquid dispersive liquid liquid microextraction of Curcumin and its spectrophotometric determination in food samples

Ultrasound-assisted ionic liquid-based dispersive liquid liquid microextraction procedure (UAIL-DLLME) was developed for determination of trace levels of patent blue V prior to its determination by UV-visible spectrophotometry. Patent blue V was extracted from 25-mL sample into a 100-mu L volume of ionic liquid, 1 -butyl- 3 -methylimidazolium hexafluorophosphate ([bmimil][PF6]), with the aid of sonication in an ultrasonic bath. Several variables affecting microextraction efficiency were optimized Under the optimum experimental conditions, the detection limit (3 s) was 0.68 mu g L-1, and the preconcentration factor was 100. The relative standard deviation for six replicate determinations of patent blue V was 4.5 A. The method was applied to the determination of patent blue V in food samples. The proposed procedure is effective, very simple, and fast

Spectrophotometric Detection of Rhodamine B after Separation-Enrichment by Using Multi-walled Carbon Nanotubes

A new, simple UV-Vis spectrophotometric method for the separation-preconcentration and determination of rhodamine B based on its adsorption onto multi-walled carbon nanotubes has been described. The effects of parameters for the quantitative recoveries of rhodamine B, including pH, flow, sample volumes, etc., were optimized. Matrix effects of concomitant ions or other dyes were also examined. The preconcentration factor and LOD were calculated as 125 and 0.80 mu g/L, respectively. The procedure was applied to the spectrophotometric detection of rhodamine B in a soft drink, dialysis water, textile industry wastewater, and nail polish samples

Flame Atomic Absorption Spectrometric Determination of Gold After Solid-Phase Extraction of Its 2-Aminobenzothiazole Complex on Diaion SP-207

An SPE of Au (III) on a 2-aminobenzothiazole coated Diaion SP 207-column system has been developed. The parameters, including pH of solution, amount of 2-aminobenzothiazole, eluent type, sample volume, and flow rates, were examined. The effects of alkali, alkali earth, and some metals were also studied. The recovery values at optimal conditions and detection limits for Au (Ill) were found as >95% and 3.8 mu g L-1, respectively. The factor of preconcentration was 250. The RSD value was <5%. The capacity of adsorption for the resin was 10.4 mg g(-1). The accuracy of the method was evaluated by the use of CDN-GS-3D gold-certified reference material. The proposed procedure for the determination of gold was applied to water, mine, soil, and anodic slime samples

Ultrasound-Assisted Ionic Liquid-Dispersive Liquid-Liquid of Curcumin in Food Samples Microextraction and Its Spectrophotometric Determination

Background: A rapid and new ultrasound-assisted ionic liquid-dispersive liquid-liquid microextraction method (UA-IL-DLLME) was presented for the determination of curcumin by spectrophotometry. Objective: To determine trace levels of curcumin in food samples by using green and low-cost method development. Methods: 1-Butyl-3-methylimidazolium hexafluorophosphate was used to extract curcumin from sample solutions with the aid of sonication. Optimum extraction efficiency was determined by examining extraction solvents, pH, centrifugation speed, time, sonication period, and temperature. The influences of diverse ions on the recovery of curcumin were examined. The concentration of curcumin in the final solution was measured by spectrophotometer at 425 nm. Results: The enrichment factor achieved was 167. The LOD and the RSD were 0.51 mu g/L and 4.3%, respectively. The presented method was performed to detect curcumin in 20 food samples. Conclusions: The presented UA-IL-DLLME method is simple, low in cost, environmentally friendly, rapid, and sensitive and requires minimal use of toxic organic solvents. Highlights: A microextraction method was applied to increase sensitivity. Higher enrichment factors and lower detection limits were observed. The proposed technique is easy, cost-effective, accurate, and precise