Quantitative Separation (quantitative + separation)

Distribution by Scientific Domains

Selected Abstracts

Quantitative separation of oxytocin, norfloxacin and diclofenac sodium in milk samples using capillary electrophoresis

Amber R. Solangi
Abstract A simple, sensitive and rapid method has been developed for simultaneous separation and quantification of three different drugs: oxytocin (OT), norfloxacin (NOR) and diclofenac (DIC) sodium in milk samples using capillary electrophoresis (CE) with UV detection at 220 nm. Factors affecting the separation were pH, concentration of buffer and applied voltage. Separation was obtained in less than 9 min with sodium tetraborate buffer of pH 10.0 and applied voltage 30 kV. The separation was carried out from uncoated fused silica capillary with effective length of 50 cm with 75 m i.d. The carrier electrolyte gave reproducible separation with calibration plots linear over 0.15,4.0 g/mL for OT, 5,1000 g/mL for NOR and 3,125 g/mL for DIC. The lower limits of detection (LOD) were found to be 50 ng/mL for OT, and 1 g/mL for NOR and DIC. The method was validated for the analysis of drugs in milk samples and pharmaceutical preparations with recovery of drugs within the range 96,100% with RSD 0.9,2.8%. Copyright 2009 John Wiley & Sons, Ltd. [source]

Ion imprinted polymer particles for separation of yttrium from selected lanthanides

Ramakrishnan Kala
Abstract Lanthanide(III) (Dy, Gd, Tb and Y) ion imprinted polymer (IIP) materials were synthesized via single pot reaction by mixing lanthanide imprint ion with 5,7-dichloroquinoline-8-ol, 4-vinylpyridine, styrene, divinylbenzene and 2,2,-azobisisobutyronitrile in 2-methoxyethanol porogen. The imprint ion was removed by stirring the above materials (after powdering) with 6 mol/L HCl to obtain the respective lanthanide IIP particles. Y-Dy, Y-Gd and Dy-Gd polymer particles were obtained by physically mixing equal amounts of the respective leached individual lanthanide(III) particles. Control polymer (CP) particles were similarly prepared without imprint ion. Application of the above synthesized polymer particles was tested for separation of Y from Dy, Gd and Tb employing batch and column SPE methods using inductively coupled plasma atomic emission spectrometry for the determination. Optimization studies show that Y present in 500 mL can be preconcentrated using Dy-Gd IIP particles and eluted with 20 mL of 1.0 mol/L of HCl, providing an enrichment factor of , 25. Dy-Gd IIP particles offer higher selectivity coefficients for Y over other lanthanides compared to other IIP particles and commercial liquid,liquid extractants. Selectivity studies for Y over other coexisting inorganic species (other than lanthanides) were also conducted and the results obtained show a quantitative separation of Y from other inorganics other than Cu(II) and Fe(III). Furthermore, both batch and column studies indicate the purification of yttrium concentrate from 55.0 0.2 to 65.2 0.2% in a single stage of operation. [source]

Gas chromatographic separation of saturated aliphatic hydrocarbon enantiomers on permethylated ,-cyclodextrin

CHIRALITY, Issue S1 2003
Uwe J. Meierhenrich
Abstract Enantiomers of chiral aliphatic hydrocarbons are generally difficult to separate because they lack functional groups to be derivatized in order to generate diastereomers. The systematic and quantitative separation of a series of branched hydrocarbon enantiomers using a chiral cyclodextrin stationary phase and a cryostat-controlled gas chromatograph is described. The use of a cryogenic system allows the improvement of separations for various chiral aliphatic hydrocarbons. The molecular cyclodextrin-based mechanism of the achieved enantiomeric separations is discussed briefly. Possible applications of this analytical technique are summarized, with special emphasis on the planned enantiomeric separation experiment on a cometary nucleus. Chirality 15:S13,S16, 2003. 2003 Wiley-Liss, Inc. [source]

Microchip micellar electrokinetic chromatography separation of alkaloids with UV-absorbance spectral detection

Carl I. D. Newman
Abstract A microchip device is demonstrated for the electrophoretic separation and UV-absorbance spectral detection of four toxic alkaloids: colchicine, aconitine, strychnine, and nicotine. A fused-silica (quartz) microchip containing a simple cross geometry is utilized to perform the separations, and a miniature, fiber-optic CCD spectrometer is coupled to the microchip for detection. Sensitive UV-absorbance detection is achieved via the application of online preconcentration techniques in combination with the quartz microchip substrate which contains an etched bubble-cell for increased pathlength. The miniature CCD spectrometer is configured to detect light between 190 and 645,nm and LabView programming written in-house enables absorbance spectra as well as separations to be monitored from 210 to 400,nm. Consequently, the configuration of this microchip device facilitates qualitative and quantitative separations via simultaneous spatial and spectral resolution of solutes. UV-absorbance limits of quantification for colchicine, 20,,M (8,mg/L); strychnine, 50,,M (17,mg/L); aconitine, 50,,M (32,mg/L); and nicotine, 100,,M (16,mg/L) are demonstrated on the microchip. With the exception of aconitine, these concentrations are ,20-times more sensitive than lethal dose monitoring requirements. Finally, this device is demonstrated to successfully detect each toxin in water, skim milk, and apple juice samples spiked at sublethal dose concentrations after a simple, SPE procedure. [source]