A rapid screening procedure for some “street-drugs” by thin-layer chromatography

Abstract Thin-layer chromatography on silica gel may be used for the determination of chlorinated pesticide residues in some plant extracts without prior cleanup, thus eliminating the possible loss of pesticides during the cleanup procedure. Rapid screening of a large number of samples is thus possible with consequent saving of time and labor. When necessary, thin-layer chromatography may be used as a prior cleanup for gas chromatography.

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Rapid Screening of Pharmaceuticals by Thin-Layer Chromatography: Analysis of Essential Drugs by Visual Methods

Journal of AOAC International ◽

10.1093/jaoac/78.1.41 ◽

1995 ◽

Vol 78 (1) ◽

pp. 41-49 ◽

Cited By ~ 8

Author(s):

Allen S Kenyon ◽

Paul E Flinn ◽

Thomas P Layloff

Keyword(s):

Thin Layer ◽

Thin Layer Chromatography ◽

The United States ◽

World Health ◽

Rapid Screening ◽

Visual Methods ◽

Screening Process ◽

Standard Dosage ◽

Essential Drugs ◽

Layer Chromatography

Abstract A method for rapidly screening pharmaceuticals by thin-layer chromatography has been designed for use in areas with limited resources and by operators with limited training. An apparatus for performing the analysis in a plastic bag under equilibrium conditions was designed. Results can be reproduced by different operators and in different locations. The analysis can be performed without electricity or in a remote area, away from a laboratory. It is especially suited for field use in developing countries. The method is low cost, maintenance-free, fast, and reliable; it also uses limited volumes of solvents. The analyses can be performed without weighing if reference materials can be supplied in tablet form, provided the drug content is listed and only one unit is required for each analysis. All procedures were developed for the analysis of drugs from a partial list of essential drugs established by the World Health Organization. Three drugs were selected and prepared in the form of reference tablets. Comparisons with the analyses of the drugs in standard dosage forms were made by using reference tablets and primary USP standards. Comparable results were obtained, proving that the screening process can be conducted by using reference tablets and without weighing either the sample or the reference. The method has been successfully demonstrated and used in Swaziland, by high school teachers in the United States, and by personnel from the Ministry of Health in Saudi Arabia. Personnel can be trained in a short time to perform screening analysis of drugs.

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SCREENING OF THE ANTIOXIDANT ACTIVITY OF CRUDE EXTRACTS IN 86 ALGAE SPECIES FROM EL JADIDA COAST (MOROCCO)

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2019v11i3.28666 ◽

2019 ◽

pp. 54-61 ◽

Cited By ~ 1

Author(s):

Fatima Chibi ◽

Halima Rchid ◽

Wafa Arsalane ◽

Rachid Nmila

Keyword(s):

Antioxidant Activity ◽

Thin Layer ◽

Thin Layer Chromatography ◽

Algal Species ◽

Marine Macroalgae ◽

Rapid Screening ◽

Fucus Spiralis ◽

El Jadida ◽

Promising Source ◽

Layer Chromatography

Objective: This work aimed to screen the antioxidant activity of marine macroalgae from the Moroccan Atlantic coast (region of El Jadida). Methods: Evaluation of the antioxidant activity of different collected species, lyophilized and extracted with a solvent mixture chloroform/methanol (2/1; v/v) was conducted according to two techniques, first by thin layer chromatography (tlc) then by spectrophotometry, using a free radical 2,2-diphenyl-1-picrylhydrazyl (dpph). The sampling on a distance of 110 km allowed to harvest 86 algal species (16 brown algae, 47 red algae, 14 green algae and 9 algae being identified). Results: The analysis by thin layer chromatography reveals an antioxidant activity in nearly half of harvested algal species (52.32 %). This activity varies depending on the concentration of the extract and in function of incubation time in the presence of dpph. The monitoring of the kinetics of degradation of dpph by spectrophotometer in the presence of extracts which were active by tlc allowed to confirm the results and select the most active algal species based on the percentage of remaining dpph in the medium after 120 min of reaction: Fucus spiralis (17.02 %), Cyctoseira ericoides (12.16 %) (Phaeophyceae), and Gracilaria multipartita (36%), Halopitys incurvus (5%) (Rhodophyceae). Conclusion: The results show that the methodology adopted in this work is reliable and can be used for rapid screening of antioxidant property in plants and the species: Fucus spiralis, Cyctoseira ericoides, Gracilaria multipartita, and Halopitys incurvus can be a promising source of natural compounds endowed with high antioxidant potential.

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