scholarly journals A validated method for coumarin quantification in Meliloti herba and its ethanolic extracts using micellar thin-layer chromatography

2021 ◽  
Vol 5 (1) ◽  
pp. 013-018
Author(s):  
Verushkin Aleksey G ◽  
Kulikov Artem Yu ◽  
Kutsanyan Andranik A

A micellar thin-layer chromatography method for the quantitative determination and validation of coumarin in Meliloti herba and its ethanolic extracts was developed and validated. For achieving good determination, the mobile phase of 5 x 10-4 mol/L Tween-80 in a mixture propanol-2 – water (5:95 v/v) was used. Densitometric determination was carried out at 275 nm. The calibration curve was linear in the range of 0.1-2.5 μg per band. The proposed method is simple, rapid, precise and accurate; replacing hazardous solvents by greener ones correspond to the modern requirements in “Green chemistry” concepts. The obtained data can be used for the routine analysis of coumarin in medical plant and extracts.

Author(s):  
L. S. Logoyda ◽  
D. B. Korobko

Introduction. Thin layer chromatography, or TLC, is a method for analyzing mixtures by separating the compounds in the mixture. TLC can be used to help determine the number of components in a mixture, the identity of compounds, and the purity of a compound.The aim of the study – to develop a thin layer chromatography method for the estimation enalapril in medicines.Research methods. The present study is assessed system solvents of enalapril maleate for thin layer chromatography.Results and Discussion. Method of identification of enalapril maleate in medicines by TLC was developed. We established that the most optimal Rf observed using mobile phase: ammonia (25 %) – propanol (30:70). The detection limits of enalapril maleate in this system are 0.2 mcg. However, those mobile phase is the most express. We explored the validation characteristics – specificity and suitability of the chromatographic system that met, the eligibility criteria established by the SPU.Conclusions. We developed chromatographic methods of identification of enalapril maleate in medicines. The proposed method is rapid, economical and simple.


2020 ◽  
Vol 32 (3) ◽  
pp. 199-202
Author(s):  
Y. Gu ◽  
B. Zeng ◽  
J. Sherma

High-performance thin-layer chromatography (HPLTC)–densitometry methods are described for the analysis of the anti(retro)virals dolutegravir (D), lamivudine (L), and tenofovir disoproxil fumarate (TDF) in a pharmaceutical tablet product. To the best of our knowledge, no previous quantitative planar chromatography method has been reported in the literature for this combination formulation. The method for L was transferred from a thin-layer chromatography (TLC) screening method published in the Global Pharma Health Fund (GPHF) Minilab Manual designed for identification of counterfeit and substandard drug products using a model process published earlier. D and TDF are not included in the list of drugs for which TLC screening methods are published for the Minilab, but HPTLC–densitometry procedures were developed for them using the transfer process guidelines. L was analyzed simultaneously with TDF on Merck Premium Purity silica gel 60 F plates using the mobile phase ethyl acetate–methanol–acetone–concentrated ammonium hydroxide (30:7:3:1) and densitometric scanning at 254 nm. D was analyzed on a second plate by scanning at 366 nm after chromatography with the chloroform–methanol–formic acid (32:8:2) mobile phase. Data for all three drugs are shown to meet the requirements of the model transfer process for calibration curve r values, assay of tablets relative to their label values, peak purity/peak identity tests, and validation by standard addition analysis of samples spiked at 50%, 100%, and 150% of the label value of active ingredients. A TLC screening method for TDF in the combination product was developed and published online with open access.


The possibility of separation of oleic and stearic acids with mobile phases on the basis of surfactants was estimated by the method of a thin-layer chromatography. The influence of surfactant's type and concentration on the retention parameters of the studied acids when using of normal-phase plates for a thin-layer chromatography of Sorbfil UV-254 is investigated in the work. The influence on mobility of oleic and stearic acids of the anionic sodium n-dodecylsulphate, cationic cetylpyridinium chloride and non-ionic Tween-80 in the range of concentration from 1·10-5 mol/l to 0.1 mol/l is estimated. The mixed mobile phases on the basis of two last surfactants taken in various concentrations are also investigated. The рН of eluents was varied in the range from 1 to 9. The addition of 2-propanol into the mobile phase containing surfactant didn't lead to improvement of acids' distribution efficiency. The best results have been received with the eluent, containing 1·10-5 mol/l of cetylpyridinium chloride and boric buffer solution with pH 9. Preliminary modification of silica gel surface with cetylpyridinium chloride did not change the results of chromatography. For clarification of relation of acids' retention with a length of a hydrophobic fragment, and, therefore, a contribution of hydrophobic interactions, in system with the mixed mobile phase on the basis of cetylpyridinium chloride and Tween-80 at pH 3 formic acid, acetic acid, propionic acid, hexanoic acid and myristic acid were analyzed. The smallest mobility was observed for myristic acid (lgPo/w=6.09±0.19) that indicates very strong hydrophobic interactions of acid with the surface of silica gel modified by surfactants. Such interactions are the main reason of bad mobility of studied oleic (lgPo/w=7.7±0.2) and stearic (lgPo/w=8.22±0.19) acids in system with the surfactant-containing eluents. For the manifestation of acidic zones after chromatography, a solution of phosphomolybdic acid, a solution of rhodamine B, a solution of sulfuric acid and an iodine chamber were tested. The best visualization of TLC-сhromatogram is obtained after sprinkle the plates by 6% solution of sulfuric acid in ethanol with their subsequent heating at 110 °C.


2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Andrzej Czyrski ◽  
Bartłomiej Kupczyk

Mercaptopurine and its derivatives are used in the treatment of leukemia. To estimate their lipophilicity, a simple and novel thin layer chromatography method was developed. The mobile phase was the mixture of acetonitrile and water. The acetonitrile content varied by 5% from 50% to 80%. The linear relationship between and for substances with known lipophilicity was found. The lipophilicity of purine derivatives was worked out from the calibration curve. The most lipohilic compound was methylazathioprine (0.64).


2021 ◽  
Vol 10 (1) ◽  
pp. 37-43
Author(s):  
Amal Rezka Putra ◽  
◽  
Khoirunnisa Fauziah Asyikin ◽  
Robertus Dwi Hendarto ◽  
Agus Ariyanto ◽  
...  

Radiochemical purity testing of [153Sm]Sm-EDTMP usually uses the Thin Layer Chromatography method. The mobile phase used is a mixture of 25% ammonia and water. However, the lowest ratio of 25% ammonia in the mobile phase is unknown. Therefore, research related to the use of the lowest concentration in the radiochemical purity test of [153Sm]Sm-EDTMP is necessary. This research method includes labelling of EDTMP using Samarium-153, preparation of the mobile phase with variations in the concentration of 25% ammonia: water, radiochemical purity test and data analysis using t-test statistics. The results of this study are the concentration of 25% ammonia: water (1: 9) to (1: 200) still shows good separation with Rf of [153Sm]SmCl3 and [153Sm]Sm-EDTMP at 0.0, 1.0 respectively, whereas with a thinner concentration of ammonia indicates less optimal separation with Rf [153Sm]SmCl3 at 0.35 to 1.0. Comparison of concentrated ammonia concentrations of 1: 9 and dilute 1: 200 was performed using a statistical t-test. The results of the data analysis showed that the two methods were not significantly different, indicated by the t-value of 0.82 less than 2.78. The conclusion of this study is that the lowest concentration of 25% ammonia and water in the radiochemical purity test of [153Sm]Sm-EDTMP is 1: 200.


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