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Validated method to determine (±)-gossypol in Candida tropicalis culture by high-performance liquid chromatography

Cheng C., Cun-Xi N., Jing L., Yong-Qiang W., Yan-Feng L., Wen-Xia G., Wen-Ju Z.

Acta Chromatographica

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2018

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Vol. 30, no. 4

269--273

EN

A validated high-performance liquid chromatography (HPLC) method has been developed to analyze the (±)-gossypol in the selection of strains of Candida tropicalis culture. Since gossypol was easily degraded and oxidized, the addition of antioxidant NADPH-Na4 and acetone extraction was chosen to prevent gossypol degradation and gradient elution assay was applied to obtain gossypol resolution. Concentrations of gossypol in C. tropicalis ZD-3 culture 20 μg/mL were determined, and concentration–time profiles were observed. Linearity of the gossypol standard curve by HPLC area method was ranged from 0.1 to 20 μg/mL with Y = 26.954 × X − 29.547, R2 = 0.9991, and n = 3, with limit of detection (LOD) of 50 ng/mL and lower limit of quantification (LLOQ) of 500 ng/mL. The recovery rate is dose-dependent and ranged from 85.3% to 103.5%. It is a rapid and reliable HPLC method for gossypol quantization in microorganism culture which could be applied in solid fermentation in the feed industry.

2

Jednoczesne oznaczanie nieorganicznych anionów oraz kwasów karboksylowych metodą chromatografii jonowej z elucją gradientową

Kończyk J., Michalski R.

Chemistry, Environment, Biotechnology

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2016

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Vol. 19

111--120

PL

Chromatografia jonowa jest referencyjną metodą oznaczania głównych nieorganicznych anionów i kationów w wodach i ściekach. Wraz z jej rozwojem rozszerza się zakres zastosowań o nowe rodzaje analitów i matryc. Przedmiotem badań była możliwość zastosowania chromatografii jonowej z detekcją konduktometryczną w układzie elucji gradientowe j do oznaczania wybranych nieorganicznych anionów oraz kwasów karboksylowych w próbkach żywności na przykładzie naparów herbat ziołowych. Przedstawiono wpływ składu eluentu i jego gradientu na jednoczesne rozdzielanie jonów: F – , Cl– , NO2 – , NO3 – , Br– , PO4 3– , SO4 2– oraz kwasów: mrówkowego, octowego, szczawiowego i cytrynowego w próbkach naparów z herbat.

EN

Ion chromatography is the reference method for determining the major inorganic anions and cations in water and wastewater. Along with the developments its applications expand to the range of new types o f analytes and matrices. The object of the study was the possibility of using ion chromatography with conductivity de tection and gradient elution of selected inorganic anions and carboxylic acids in food samples for example o f herbal tea infusions. The influence of eluent composition and its gradient on the simultaneous separation o f ions: F– , Cl– , NO2– , NO3 – , Br– , PO4 3– , SO4 2– , as well as formic acid, ace tic acid, oxalic acid, and citric acid in samples of teas was tested.

3

Gradient elution LC-MS determination of dasatinib in rat plasma and its pharmacokinetic study

Wen C, Zhang Q., He Y., Deng M, Wang X., Ma J.

Acta Chromatographica

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2015

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Vol. 27, no. 1

81--91

EN

A sensitive and simple liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) method for determination of dasatinib in rat plasma using one-step protein precipitation was developed. After addition of carbamazepine as internal standard (IS), protein precipitation by acetonitrile was used as sample preparation. Chromatographic separation was achieved on an SB-C18 (2.1 mm × 150 mm, 5 μm) column with methanol-0.1% formic acid as mobile phase with gradient elution. Electrospray ionization (ESI) source was applied and operated in positive ion mode; selective ion monitoring (SIM) mode was used to quantification using target fragment ions m/z 488.2 for dasatinib and m/z 338.7 for the IS. Calibration plots were linear over the range of 10–1000 ng mL−1 for dasatinib in rat plasma. Lower limit of quantification (LLOQ) for dasatinib was 10 ng mL−1. Mean recovery of dasatinib from plasma was in the range 82.2%–93.6%. Relative standard deviation (RSD) of intra-day and inter-day precision were both less than 8%. This developed method is successfully used in pharmacokinetic study of dasatinib in rats.

4

Development and validation of a gradient elution high-performance liquid chromatographic method for determination of talinolol in rat plasma: Application to a preclinical food-drug interaction study

Mahgoub H, Hanafy A., Bamane F. H., Radwan A. E.

Acta Chromatographica

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2015

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Vol. 27, no. 1

67--79

EN

A sensitive and reproducible high-performance liquid chromatographic (HPLC) method for determination of talinolol (TAL) in rat plasma was developed and validated using pindolol (PIN) as an internal standard. Both TAL and PIN were separated on a Zorbax Eclipse XDB C18 column by gradient elution with 0.1% aqueous formic acid and acetonitrile as the mobile phase. Detection was performed using fluorescence measurement at λex 249 nm and λem 333 nm. The method was validated and found to be linear in the range of 10–2000 ng mL−1. The limit of quantification was 10 ng mL−1 based on 100 μL of plasma. The variations for intra- and inter-day precision were less than 10%, and the accuracy values were between 92% and 102.9%. The extraction recoveries were more than 82%. The assay was successfully applied to an in-vivo pharmacokinetic study of TAL in rats that were administered a single oral dose of 10 mg kg−1 TAL. The maximum concentration (Cmax) and the area under the plasma concentration-time curve (AUC0–12) were 0.369 ± 0.024 μg mL−1 and 1.429 ± 0.027 μg h mL−1, respectively. The modulatory effect of apricot juice on P-glycoprotein-related efflux carriers was also investigated. Co-administration of apricot juice resulted in a significant increase of the amount of TAL in plasma (Cmax and AUC0–12 were 0.679 ± 0.021 and 2.357 ± 0.079, respectively; p < 0.05).

5

Development of gradient HPLC-DAD method for assay of ternary mixture containing amebicide and analgesic drugs

Youssef R. M.

Acta Chromatographica

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2014

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Vol. 26, no. 1

67--80

EN

Validated gradient high-performance liquid chromatography-diode array detection (HPLC-DAD) method has been developed for simultaneous determination of diloxanide furoate (DIL), mebeverine hydrochloride (MBV), and metronidazole (MET) in their pharmaceutical preparation. This method was based on a reversed-phase HPLC separation of the cited drugs on a C-18 column (150 mm × 4.6 mm, 5 μm) with a gradient elution system of 0.05 M phosphate buffer with 1% (v/v) of triethylamine adjusted to pH 3.0-methanol as the mobile phase at the flow rate of 1.0 mL min -1. The separation was carried out at ambient temperature. Quantitation was achieved with DAD detection at 260 nm for DIL and MEB, and at 320 for MET based on peak area with linear calibration curves at concentration ranges 4–30, 1–20, and 1–30 μg mL -1 for DIL, MEB, and MET, respectively. The proposed chromatographic method was successfully applied to the determination of the investigated drugs in pharmaceutical preparation. It was validated in compliance with International Conference on Harmonization (ICH) guidelines, in terms of linearity, accuracy, precision, robustness, limits of detection, and quantitation and other aspects of analytical validation.