Effect of the distance moved by the solvent on the rf values in circular chromatography

By conducting the toxicological analysis it is meaningful to determine the analytical system that could identify simultaneously several medicinal preparations quickly and precisely. The purpose of this work was to create and validate the method of thin-layer chromatography that would be suitable to separate the components of antidepressant mixture (amitriptyline hydrochloride, paroxetine hydrochloride, sertraline hydrochloride, fluvoxamine maleate and buspirone hydrochloride) and to identify them. The system was validated with regard to the sensitivity, repetition of data, resistance and particularity. The solvent systems with potential of high separation of components in their mixture were created: acetonitrile, methanol, ammonia solution 25 percent (85:10:5); acetonitrile, methanol, ammonia solution 25 percent (75:20:5); dichlormethane, 1,4-dioxane, ammonia solution 25 percent (50:45:5); dichlormethane, 1,4-dioxane, ammonia solution 25 percent (42:55:3); trichlormethane, 1,4-dioxane, ammonia solution 25 percent (25:70:5); trichlormethane, 1,4-dioxane, ammonia solution 25 percent (60:36:4). One of the most suitable solvent systems for separation of the analyzed mixture (sertraline, amitriptyline, paroxetine, buspirone, fluvoxamine) was determined – acetonitrile, methanol, ammonia solution 25 percent (85:10:5). When this solvent system was used, the average Rf values of the analyzed compounds differed the most. Validation was conducted – the relative standard deviation (RSD, percent) of the average Rf value of the analyzed compounds varied from 0,6 to 1,8 percent and did not exceed the permissible error of 5 percent. The sensitivity of methodology was determined by assessing the intensity of the mixture’s spots on the chromatographic plate. The detection limit of buspirone was 0,0012 µg; sertraline – 0,0008 µg; amitriptyline – 0,0004 µg; fluvoxamine – 0,0004 µg; paroxetine – 0,0008 µg. The resistance of results to the changed conditions – it was determined that when the amounts of the solvents acetonitrile and methanol were increased or decreased to two milliliters, the average Rf values of the analyzed compounds did not change statistically significantly

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Phytochemical evaluation of leaf extracts of Naringi crenulata (roxb.) Nicolson

International Journal of Bioassays ◽

10.21746/ijbio.2016.11.0020 ◽

2016 ◽

Vol 5 (11) ◽

pp. 5110

Author(s):

Sartaj Ahmad Allayie ◽

Mushtaq Ahmed Parray* ◽

Bilal Ahmad Bhat ◽

S. Hemalatha

Keyword(s):

Quantitative Analysis ◽

Solvent System ◽

Great Promise ◽

Phytochemical Analysis ◽

Bioactive Constituents ◽

Leaf Extracts ◽

Traditional Medicines ◽

The People ◽

Wide Range ◽

Rf Values

The use of traditional medicines holds a great promise as an easily available source as effective medicinal agents to cure a wide range of ailments among the people particularly in tropical developing countries like India. The present study investigates the qualitative and quantitative analysis of the major bioactive constituents of N. crenulata leaf extracts. The extractive values of aqueous, acetone and chloroform extracts were found to be 11.34, 4.24 and 6.06 respectively. Qualitative phytochemical analysis of these three solvent extracts confirm the presence of Alkaloids, Saponins, Flavonoids and Phenolic compounds in all the three extracts; however, these phytochemicals were more significant in aqueous extract. Quantitative analysis was carried out using TLC method by different solvent system. Amongst various solvent systems, Butanol: acetic acid: water (9: 0.9: 0.1 v/v/v) shows maximum resolution and number of spots produced at long UV (365 nm) and under iodine vapours. The TLC chromatograms constituted different coloured phytochemical compounds with different Rf values. It can be conveniently used to evaluate the quality of different area samples. This indicates that the leaves can be useful for treating different diseases because the therapeutic activity of a plant is due to the presence of particular class of compounds and thus can serve as potential sources of useful drugs in future.

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Impact of inter-reader contouring variability on textural radiomics of colorectal liver metastases

European Radiology Experimental ◽

10.1186/s41747-020-00189-8 ◽

2020 ◽

Vol 4 (1) ◽

Author(s):

Francesco Rizzetto ◽

Francesca Calderoni ◽

Cristina De Mattia ◽

Arianna Defeudis ◽

Valentina Giannini ◽

...

Keyword(s):

Liver Metastases ◽

Hausdorff Distance ◽

Intraclass Correlation ◽

Three Dimensional ◽

Liver Lesion ◽

Dice Coefficient ◽

Rf Values ◽

Enhanced Computed Tomography ◽

Relative Change ◽

The Impact

Abstract Background Radiomics is expected to improve the management of metastatic colorectal cancer (CRC). We aimed at evaluating the impact of liver lesion contouring as a source of variability on radiomic features (RFs). Methods After Ethics Committee approval, 70 liver metastases in 17 CRC patients were segmented on contrast-enhanced computed tomography scans by two residents and checked by experienced radiologists. RFs from grey level co-occurrence and run length matrices were extracted from three-dimensional (3D) regions of interest (ROIs) and the largest two-dimensional (2D) ROIs. Inter-reader variability was evaluated with Dice coefficient and Hausdorff distance, whilst its impact on RFs was assessed using mean relative change (MRC) and intraclass correlation coefficient (ICC). For the main lesion of each patient, one reader also segmented a circular ROI on the same image used for the 2D ROI. Results The best inter-reader contouring agreement was observed for 2D ROIs according to both Dice coefficient (median 0.85, interquartile range 0.78–0.89) and Hausdorff distance (0.21 mm, 0.14–0.31 mm). Comparing RF values, MRC ranged 0–752% for 2D and 0–1567% for 3D. For 24/32 RFs (75%), MRC was lower for 2D than for 3D. An ICC > 0.90 was observed for more RFs for 2D (53%) than for 3D (34%). Only 2/32 RFs (6%) showed a variability between 2D and circular ROIs higher than inter-reader variability. Conclusions A 2D contouring approach may help mitigate overall inter-reader variability, albeit stable RFs can be extracted from both 3D and 2D segmentations of CRC liver metastases.

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Observed and calculated RF values of several synthetic peptides in paper chromatography

Journal of Chromatography A ◽

10.1016/s0021-9673(00)93454-x ◽

1958 ◽

Vol 1 ◽

pp. 513-520 ◽

Cited By ~ 21

Author(s):

Thomas B. Moore ◽

Carl G. Baker

Keyword(s):

Paper Chromatography ◽

Synthetic Peptides ◽

Rf Values

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A nomogram for measurement of Rf values on chromatograms

Biochemical Education ◽

10.1016/0307-4412(85)90075-5 ◽

1985 ◽

Vol 13 (4) ◽

pp. 177-178

Author(s):

AM Diwan

Keyword(s):

Rf Values

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DEVELOPMENT OF HPTLC METHOD FOR THE ESTIMATION OF ONDANSETRON AND RANITIDINE IN COMBINED DOSAGE FORM

INDIAN DRUGS ◽

10.53879/id.52.12.10321 ◽

2015 ◽

Vol 52 (12) ◽

pp. 42-48

Author(s):

P. J. Patel ◽

◽

D. A Shah ◽

F. A. Mehta ◽

U. K. Chhalotiya

Keyword(s):

Thin Layer ◽

Stationary Phase ◽

Thin Layer Chromatography ◽

Silica Gel ◽

High Performance ◽

Dosage Form ◽

Solvent System ◽

Rf Values ◽

Layer Chromatography ◽

Hptlc Method

A simple, sensitive and precise high performance thin layer chromatographic (HPTLC)method has been developed for the estimation of ondansetron (OND) and ranitidine (RAN) in combination. The method was employed on thin layer chromatography (TLC) and aluminium plates were precoated with silica gel 60 F254 as the stationary phase, while the solvent system was methanol. The Rf values were observed to be 0.5 ± 0.02, and 0.3 ± 0.02 for OND and RAN, respectively. The separated spots were densitometrically analyzed in absorbance mode at 299 nm. This method was linear in the range of 25-300 ng/band for OND and 50-600 ng/band for RAN. The limits of detection for OND and RAN were found to be 3.47 and 1.83 ng/band, respectively. The limits of quantification for OND and RAN were found to be 10.53 and 5.55 ng/band, respectively. The proposed method was validated with respect to linearity, accuracy, precision and robustness. The method was successfully applied to the estimation of OND and RAN in combined dosage form.

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FINGER PRINTING ANALYSIS OF THE PHENOLS FROM HOLOPTELEA INTEGRIFOLIA (ROXB.) PLANT LEAVES USING HPTLC

INDIAN DRUGS ◽

10.53879/id.54.09.10727 ◽

2017 ◽

Vol 54 (09) ◽

pp. 67-71

Author(s):

R. C. Sutar ◽

◽

D. S Musmade

Keyword(s):

High Performance ◽

Methanolic Extract ◽

Phytochemical Analysis ◽

Phytochemical Screening ◽

Plant Leaves ◽

Methanol Extracts ◽

Finger Printing ◽

Rf Values ◽

Layer Chromatography ◽

Tungsten Lamp

The present study was conducted to identify the phenols from methanol extracts (MHI) of medicinally and economically useful leaves of Holoptelea integrifolia (Roxb.) plant using High Performance Thin Layer Chromatography (HPLC) technique. Preliminary phytochemical screening was done and HPTLC studies were carried out on CAMAG HPTLC system equipped with Linomat V applicator (Switzerland). Densitometric scanning was performed with Camag TLC scanner IV in the reflectance absorbance mode at 540 nm and operated by Win CATS software (1.4.6 Camag) with the help of tungsten lamp. Preliminary phytochemical screening of methanolic extract of Holoptelea integrifolia showed the presence of steroids, alkaloids, flavonoids, proteins, phenols and carbohydrates. HPT LC finger printing of phenols of methanolic extract of leaf revealed seven polyvalent phytoconstituents (7 peaks) and corresponding ascending order of Rf values in the range of 0.15 to 0.75. From the results of preliminary phytochemical analysis and above Rf values, we have concluded the presence of phenols in methanol extracts.

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