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Determination of ampicillin and amoxicillin by high-performance thin-layer chromatography

Ghoulipour V., Shokri M, Waqif-Husain S.

Acta Chromatographica

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2011

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Vol. 23, no. 3

483--498

EN

A simple and fast high-performance thin-layer chromatographic method has been developed for the simultaneous determination of ampicillin and amoxicillin. Titanium(IV) silicate (a synthetic inorganic ion-exchanger)-coated thin-layer chromatography (TLC) plates were used to separate them, employing a mixture of K2HPO4 (0.1 M) + KH2PO4 (0.1 M), 1:1 (υ/υ), as mobile phase. The development time was 18 min. The plates were sprayed with fresh 1% solution of ninhydrin in ethanol. The developed method enables highly contrasted chromatograms with red purple spots in white background. Densitometric measurements were made at wavelength 546 nm using Camag TLC Scanner-3. The ampicillin and amoxicillin recovery of the total procedure were equal to 99.99 and 100.43, respectively. The procedure is quantitatively characterized. Linearities were r2 > 0.9958 and 0.9954 for ampicillin and amoxicillin, respectively, and the relative standard deviations were <0.89 and 0.61, respectively. The limits of detection were 2.9 and 1.5 ng per spot and the limits of quantification were 14.5 and 7.5 ng per spot, respectively. The method is rapid, selective, precise, and accurate and thus can be used for the routine analysis of pharmaceutical preparations in quality control laboratories of the pharmaceutical industry. The method is successfully applied for the determination of ampicillin and amoxicillin in human blood plasma and urine.

2

Analysis of tributyltin and triphenyltin in water by ionic liquid-headspace single-drop microextraction then HPLC with fluorimetric detection

Sheikhloie H, Saber-Tehrani M, Abrumand-Azar P, Waqif-Husain S.

Acta Chromatographica

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2009

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Vol. 21, no. 4

577--589

EN

A novel method using ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [C 4 MIM][PF 6 ] as extracting solvent in head-space single drop microextraction followed by HPLC with fluorimetric detection has been developed for analysis of tributyltin (TBT) and triphenyltin (TPhT) in water. Experimental conditions related to SDME performance, for example micro-drop volume, extraction time, stirring rate, salt content, and sample volume were investigated. Under the optimized conditions (micro-drop volume, 10 μL; extraction time, 30 min; stirring rate, 900 rpm; salt concentration, 6%; sample volume, 6 mL), the linear range, detection limit ( S / N = 3), and reproducibility (RSD, n = 4) were 1−100 μL -1, 0.62 μL -1, and 7.8%, respectively, for TBT, and 2−100 μL -1, 0.95 μL -1, and 8.3% for TPhT. All micro-extraction experiments were performed at room temperature (25 ± 1°C). The optimized procedure was successfully used for analysis of TBT and TPhT in deionized water and waste water. Recovery of a 25 μL -1 spike was in the range 86.9–92.1%. The method has also been used for analysis of TBT and TPhT in natural water.

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Rapid chromatographic separation of food additives on thin layers of an inorganic ion-exchanger

Purghazi K., Ghoulipour V., Waqif-Husain S., Mirzaie A.

Acta Chromatographica

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2007

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No. 18

219-225

EN

The chromatographic behaviour of ascorbic acid, benzoic acid, butylated hydroxyanisole, butylated hydroxytoluene, butyraldehyde, butyric acid, cinnamaldehyde, citric acid, ethyl acrylate, ethyl benzoate, ethyl phydroxybenzoate, fumaric acid, lactic acid, lauric acid, maleic acid, methyl p-hydroxybenzoate, oleic acid, p-hydroxybenzoic acid, propionic acid, propyl gallate, propyl p-hydroxybenzoate, salicylic acid, sodium benzoate, and sorbic acid has been studied on thin layers of stannic silicate ion-exchanger with several aqueous, organic, and mixed mobile phases. Rapid separations of one food additive from many other food additives, and ternary and binary separations, are reported.