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Micellar electrokinetic chromatographic separation and quantitative analysis of thorium, uranium, gold, and mercury from environmental ore samples

Mallah A, Memon S. Q., Khuhawar M.Y., Solangi A. R., Bhanger M. I.

Acta Chromatographica

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2011

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Vol. 23, no. 1

69--80

EN

A rapid and reliable analytical procedure has been developed for the separation and analysis of dioxouranium, thorium, gold, and mercury by micellar electrokinetic chromatography (MEKC) using bis(acetylacetone)ethylenediamine (H2AA2en) as complexing reagent. Under the optimized conditions (64 mM borate buffer containing 12.25 mM SDS and 13% acetonitrile, pH 8.0, 25 kV, 311 nm as detection wavelength) the ions were separated within 5.0 min. Linear dynamic ranges were 1–5, 8–42, 10–50, and 2–40 μg mL -1, respectively, for gold, mercury, thorium, and uranium and the respective detection limits were 0.66, 3.33, 1.6, and 3.3 μg mL -1. The applicability of method has been evaluated by application to uranium and thorium from ore samples.

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Micellar electrokinetic chromatographic separation and analysis of thorium, uranium, gold, and mercury in environmental ore samples

Mallah A, Memon S. Q., Solangi A. R., Khuhawar M. Y., Bhanger M. I.

Acta Chromatographica

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2010

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Vol. 22, no. 3

405--417

EN

A fast and reliable analytical procedure has been developed for separation and analysis of dioxouranium, thorium, gold, and mercury by micellar electrokinetic chromatography (MEKC) using bis(acetylacetone)ethylenediamine (H 2 AA 2 en) as complexing reagent. Under the optimized conditions (64 mM borate buffer containing 12.25 mM SDS and 13% acetonitrile, pH 7.99; 25 kV; detection wavelength 311 nm), other ions present were separated within 5 min. Linear dynamic ranges 1–5, 8–42, 10–50, and 2–40 μg mL -1 and detection limits 0.66, 3.33, 1.6, and 3.3 μg mL -1, respectively, were achieved for gold, mercury, thorium, and uranium. The applicability of method was evaluated by analysis of uranium and thorium in ore samples.

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Quantitative analysis of eight cephalosporin antibiotics in pharmaceutical products and urine by capillary zone electrophoresis

Solangi A. R., Memon S. Q., Khuhawar M. Y., Bhanger M. I.

Acta Chromatographica

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2007

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No. 19

81-96

EN

A simple and rapid capillary zone electrophoretic (CZE) method has been established for separation and quantification of a mixture of eight ce-phalosporins – cefadroxil (CFL), cefixime (CIX), cefuroxime sodium (CFR), ceftriaxone sodium (CTR), ceftizoxime (CFT), cefaclor (CFC), cefradine (CFD), and cefotoxime (CTA). Conditions affecting the separation were pH, buffer concentration, and applied potential. Separation was performed in less than 11 min with 50 mM sodium tetraborate buffer, pH 9.0, and an applied potential of 30 kV. Reproducible separation was achieved and calibration plots were linear over two to three orders of magnitude of analyte concentration. Limits of detection were in the range 0.5–5 µg mL–1. De-tection was by UV absorbance at 214 nm. When the method was assessed for analysis of cephalosporins in pharmaceutical preparations and in urine, relative standard deviations (RSD, n = 4) were in the range 0.3–1.9%.

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Micellar liquid chromatographic determination of aluminum as its complex with 8-hydroxyquinoline-5-sulfonic acid

Memon M., Bhanger M. I.

Acta Chromatographica

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2004

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No. 14

172-179

EN

A micellar liquid-chromatographic method is proposed for deter-mination of Al(III) as the 8-hydroxyquinoline-5-sulfonic acid derivative, with spectrofluorimetric detection. Cetyltrimethylammonium bromide, a ca-tionic surfactant (0.05 M), was used as mobile phase. The metal chelate was detected at γEx 410 and γEm 510 nm. Response to aluminum is selective in the presence of other metal ions. The method eliminates the need for addi-tion of reagent or organic modifier to the mobile phase, as is normal in RP HPLC. Under optimized conditions the linear range was 20–200 μg L-1 Al(III), the limit of detection 10 μg L-1, and the limit of quantification 40 μg L-1. The method was used to determine aluminum in a variety of water samples.