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Development and validation of HPLC assay method for marbofloxacin determination in veterinary chewable tablets

Oliveira K. R. W., Sversut R. A., Singh A. K., Amaral M. S., Kassab N. M.

Acta Chromatographica

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2019

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Vol. 31, no. 4

291--293

EN

The present study aimed to develop and validate an analytical method for determination of marbofloxacin (MAR) in veterinary chewable tablets. The isocratic reversed-phase chromatographic method was developed and validated using a Vertisep®, RP C18 column (150 mm × 4.6 mm, 5.0 μm). The mobile phase was composed of water–acetonitrile (55:45, v/v) with pH adjusted to 3.0 with ortho-phosphoric acid and a flow rate set at 0.4 mL/min. The proposed method was validated for linearity in a concentration range of 2.5 to 17.5 μg/mL with a correlation coefficient of 0.99991. The mean content of MAR found in chewable tablets was 104.40% with RSD below 2%. The accuracy expressed as average recovery of the proposed method was 98.74%, and the precision expressed as relative standard deviation among repeated analysis was 0.55%. The method has adequate sensitivity with detection and quantitation limits of 0.25 and 0.81 μg/mL, respectively. Based on the presented results and according to the ICH and AOAC guidelines on validation of analytical methods, the proposed method was considered precise, accurate with adequate sensitivity, and robust in the MAR quantitative analysis. Therefore, the method can be used in the quality control of chewable veterinary tablets containing MAR.

2

Matrix solid-phase dispersion method coupled with high-performance liquid chromatography for the simultaneous quantification of selected compounds from freeze dry pomegranate juice

Kamal Y. T., Yusufoglu H., Alam P., Fouda A.

Acta Chromatographica

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2018

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Vol. 30, no. 3

153--157

EN

In this research, a novel method was developed for the matrix solid phase dispersion (MSPD) followed by high-performance liquid chromatography (HPLC) quantification of four marker constituents (vitamin C, gallic acid, rutin, and ellagic acid) in the freeze-dried pomegranate fruit juice. Various MSPD parameters like type of dispersant, sample–dispersant ratio, solvents, its volume, and time of extraction have been optimized after many trials. Furthermore, HPLC method has been developed and optimized for the analysis of all four components. The HPLC separation was achieved using a 250 × 4.6 mm column, particle size of 5 μm, C18 reverse phase column, with a mobile phase consisting of acetonitrile and 0.05% H3PO4, in gradient elution mode with a mobile phase flow rate of 1 mL/min, using ultraviolet (UV)–visible detection at 254 nm. All calibration curves showed good linear regression (r2 ≥ 0.9925) within test ranges. The extraction recoveries of the marker constituents analyzed by MSPD methods were found as ranging from 97.5% to 103.5%. From comparing the chromatograms, validation data and other parameters like time, labor, and feasibility, we found that MSPD technique was most suitable for the analysis as compared to conventional liquid–liquid extraction technique.

3

The simple isocratic HPLC-UV method for the simultaneous determination of reduced and oxidized glutathione in animal tissue

Begic A., Djuric A., Gobeljic B., Stevanovic I., Lukic V., Stanojevic I., Ninkovic M., Saso L., Vojvodic D., Djukic M.

Acta Chromatographica

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2017

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Vol. 29, no. 1

67--84

EN

The aim of our work was to optimize and apply simple high-performance liquid chromatography method with ultraviolet detection (HPLC-UV) for simultaneous determination of reduced (GSH) and oxidized (GSSG) glutathione in biological matrix (specifically, the rat liver tissue was used herein), since the ratio between oxidized and reduced glutathione forms (GSSG-GSH) has been recognized as an important biological marker of oxidatively depleted GSH in oxidative stress (OS)-associated diseases and poisonings. An isocratic chromatographic separation of GSH and GSSG (2.8 min and 6.3 min, respectively) was performed with the mobile phase consisted of sodium perchlorate solution (pH adjusted to 2.8) at flow rate of 1 mL min−1, detection set at 215 nm, and column temperature of 40 °C. The method offers short run time, linearity in the range of 0.01-200 μM concentration for both compounds (R2 = 1), low limits of detection and quantification (GSH: 0.18 μM and 0.56 μM, GSSG: 0.52 μM and 1.58 μM, respectively), precision, accuracy (bias < 2%), and high reproducibility. Through suitable sample handling, an overestimation of GSSG was prevented. High recovery (>99%) was achieved. The method was successfully applied for the analysis of GSH and GSSG in liver homogenates of Wistar rats intraperitoneally exposed to cadmium (Cd) (1 mg kg−1 CdCl2/21 days). Regardless of other Cd-mediated hepatotoxicity mechanisms, herein, we have exclusively interpreted/emphasized oxidative GSH depletion. The presented method is acceptable for a routine analysis of GSH and GSSG in biological matrix, while the calculated ratio GSSG-GSH is considered as a valuable OS marker.

4

Determination of selected nonsteroidal anti-inflammatory drugs in the aquatic environment

Kudlek E., Bohdziewicz J., Dudziak M.

Ecological Chemistry and Engineering. A

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2014

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Vol. 21, nr 2

177--187

EN

Obecność związków farmaceutycznych w środowisku wodnym wymusza opracowanie skutecznej metody ich monitoringu. W pracy przedstawiono opracowany sposób oznaczenia wybranych związków farmaceutycznych z grupy niesteroidowych leków przeciwbólowych i przeciwzapalnych, tj. ibuprofenu i diklofenaku. Do wydzielenia analitów zastosowano ekstrakcję do fazy stałej (SPE), a do analizy jakościowo-ilościową wysokosprawną chromatografię cieczową HPLC (UV) oraz chromatografię gazową sprzężoną z detektorem masowym (GC-MS). Opracowana procedura analityczna umożliwia rozdział i oznaczenie ilościowe mieszaniny związków farmaceutycznych z zadowalającą powtarzalnością i dokładności ą. Wyznaczone wartości stopni odzysku dają możliwość pełnej kontroli ilościowego oznaczenia badanych farmaceutyków w próbkach wodnych. Powyższa metoda może znaleźć zastosowanie do kontroli analitycznej przebiegu procesów uzdatniania wód naturalnych i doczyszczania ścieków pod kątem eliminacji związków farmaceutycznych.

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A simple HPLC method for determining 2-(3-chlorophenyloamino)-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole in brain and plasma of animals: Application to a pharmacokinetic study

Raszewski G., Juszczak M., Lemieszek M. K., Matysiak J., Niewiadomy A., Rzeski W.

Acta Chromatographica

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2014

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Vol. 26, no. 2

255--266

EN

The development, optimization, and validation of a new high-performance liquid chromatography ultraviolet (HPLC-UV) method is presented for determining 2-(3-chlorophenyloamino)-5-(2,4-dihydroxy-phenyl)-1,3,4-thiadiazole (ClABT) in biological samples of rat plasma and brain tissue. ClABT was extracted directly from a plasma supernatant fraction following protein precipitation with acetonitrile and high speed centrifugation. Reverse phase HPLC separation was performed using an ODS-2 Hypersil column with the mobile phase consisting of 0.05 M triethylammonium phosphate buffer solution in acetonitrile and methanol (120:280:600, v/v/v), at room temperature, 1.2 mL min-1 flow rate, and UV-diode-array detection (DAD), at 335 nm. A linear response was obtained between 12.5 and 2000 ng mL-1 at analytically acceptable levels of precision (intra/inter-day) and accuracy. Mean recoveries ranged from 92.7% to 107.9%. It was concluded that the method was specific and precise and thus suitable for quantitative analysis in clinical pharmacokinetic studies of ClABT.

6

Simultaneous determination of ephedra alkaloids in traditional chinese medicines by high-performance liquid chromatography

Chen Y., Li X, Chen F., Zhu Q., Luo J.

Acta Chromatographica

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2012

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Vol. 24, no. 3

475--487

EN

A rapid, simple, and practical high-performance liquid chromatographic method (HPLC) was developed and validated for the simultaneous determination of norephedrine (NME), norpseudoephedrine (NMP), ephedrine (E), pseudoephedrine (PE), and methylephedrine (ME) in traditional Chinese medicines (TCM) which contained Ephedrae Herba (Ephedra). This analysis could be accomplished within 12.5 min with an Alltima Phenyl Column by isocratic elution using a mixture of KH2PO4 (20 mM)-acetonitrile (96:4, v/v) as the mobile phase at a flow-rate of 0.6 mL min−1 and a wavelength of 210 nm. This method was successfully applied to quantify ephedra alkaloids in both Ma-xing-gan-shi decoction and Ephedra decoction. The concentration of total ephedra alkaloids (4.62 mg mL−1) in Ma-xing-gan-shi decoction was much lower than that (7.10 mg mL−1) in Ephedra decoction. Furthermore, the concentration of NME, NMP, E, PE, and ME was significantly lower in Ma-xing-gan-shi decoction than that in Ephedra decoction, respectively. The method was easily acceptable and would be popular with most analytical laboratories.

7

Speciation analysis of arsenic by HPLC-UV in highly contaminated water samples

Jedynak L., Kieroński P., Kowalska J., Golimowski J.

Chemia Analityczna

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2008

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Vol. 53, No. 4

557-568

EN

High performance liquid chromatography with UV detection at 191 nm was applied to determine four arsenic species: inorganic As(III) and As(V), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in water samples. For separation of arsenic compounds anion-exchange column was used. The influence of several parameters, such as the composition of mobile phase and the flow rate on the separation efficiency and the wavelength on detection sensitivity were investigated. The described method was applied to determine arsenic species in highly contaminated water samples. To validate the proposed method, determination of arsenic was performed simultaneously by ICP—MS method.

PL

W pracy przedstawiono zastosowanie wysokosprawnej chromatografii cieczowej z detekcj ą UV przy długości fali 191 nm do rozdzielania i oznaczania czterech form arsenu: nieorganicznego As (III) i As (V) oraz kwasów mono- i dimeryloarsenowego. Rozdzielenie związków arsenu przeprowadzono na kolumnie anionowymiennej. W celu zoptymalizowania warunków pomiaru określono skład fazy ruchomej, szybkość przepływu oraz długość fali stosowaną podczas detekcji. Wiarygodność metody sprawdzono przeprowadzając oznaczenia techniką ICP-MS.