Bafe Baykedagn; Yared Merdassa; Abera Gure
Volume 4, Issue 1 , March 2017, , Pages 25-33
Abstract
In this study, vortex-assisted low density based dispersive liquid-liquid microextraction followed by high performance liquid chromatography with ultraviolet detector has been developed for the determination of three pesticides including chlorflurenol-methyl, chlorfenvinphos, and diazinon from environmental ...
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In this study, vortex-assisted low density based dispersive liquid-liquid microextraction followed by high performance liquid chromatography with ultraviolet detector has been developed for the determination of three pesticides including chlorflurenol-methyl, chlorfenvinphos, and diazinon from environmental water samples. Different parameters influencing the extraction efficiency such as the type and volume of extraction and disperser solvent, sample pH, salt addition as well as vortex and centrifugation time were investigated and the optimal conditions were obtained. Under the optimum conditions, the calibration curves were linear in the concentration range of 8.5–100, 3.1–100 and 36.5–600 ng/mL for chlorflurenol-Methyl, chlorfenvinphos and diazinon, respectively, with coefficient of determination (r2) of 0.993 or better. The limits of detection and quantification of the analytes, which were determined at 3 and 10 signal-to-noise ratio (S/N) ranged from 0.9–11 and 3.1–36.8 ng/mL, respectively. The proposed method has been successfully applied to the analysis of real water samples. The relative recoveries (%RR) studied at two spiking concentration levels were ranging from 76–108%, with the corresponding relative standard deviation (%RSD) ranging from 1.9–9.9%. The results of study demonstrated that the proposed method is efficient for extraction and/or preconcentration of the three pesticides prior to quantitative determination utilizing HPLC–UV/Vis instrument.
Shivani A. Trivedi; Dharati M. Joshi; Samir G. Patel; Rajendra K. Patel; Archita J. Patel
Volume 2, Issue 1 , March 2015, , Pages 14-21
Abstract
The present study was aimed to develop and validate a high performace liquid chromatography method for determination of thiocolchicoside and dexketoprofen trometamol in combined dosage form. The proposed HPLC method utilizes an Agilent Eclipse C-8 column (5 µm, 250×4.6 mm) at ambient temperature. ...
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The present study was aimed to develop and validate a high performace liquid chromatography method for determination of thiocolchicoside and dexketoprofen trometamol in combined dosage form. The proposed HPLC method utilizes an Agilent Eclipse C-8 column (5 µm, 250×4.6 mm) at ambient temperature. A 23 full factorial design was performed for optimization of mobile phase for separation of two drugs. For the factorial design, the dependent variables chosen were % of acetonitrile, % of 0.1% o-phosphoric acid and pH. The optimum mobile phase consisted of acetonitrile: 0.1% o-phosphoric acid in water (41.9:58.1; pH 2.6). The flow rate was kept 1 mL/min with UV detection at 254 nm. The run time was found to be 1.41 min and 7.58 min for thiocolchicoside and dexketoprofen trometamol, respectively. The method was validated as per ICH guidelines. The calibration plots were linear in the range of 1-5 μg/mL with r2=0.998 for thiocolchicoside and 6-30 μg/mL with r2 = 0.995 for dexketoprofen trometamol. The % recovery values were found to be 98.52 ± 1.21 and 98.16 ± 1.45 for thiocolchicoside and dexketoprofen trometamol, respectively. The minimum detectable and minimum quantifiable amounts were found to be 0.11 and 0.35 μg/mL, respectively for thiocolchicoside and 1.41 and 4.38 μg/mL, respectively for dexketoprofen trometamol. The developed method could be utilized successfully in simultaneously analyzing the drugs in bulk as well as combined dosage form.
