ISSN: 0022-1198
CODEN: JFSCA
Page Count: 7

Impact of Tropical Conditions on Thin Layer Chromatography in Analytical Toxicology: High Temperatures and Moderate Humidities
Kam, BL
Professor of chemistry, University of Ouagadougou,

Dik, E
Professor of toxicology, associate professor of toxicology, research assistant, University Centre for Pharmacy,

Franke, JP
Professor of toxicology, associate professor of toxicology, research assistant, University Centre for Pharmacy,

de Zeeuw, RA
Professor of toxicology, associate professor of toxicology, research assistant, University Centre for Pharmacy,

ten Dolle, W
Professor of toxicology, associate professor of toxicology, research assistant, University Centre for Pharmacy,

(Received 10 September 1991; accepted 2 December 1991)

Abstract

The impact of high temperatures (24 to 39°C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rf^c values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions.

The impact of high to extremely high humidities (70 to 100%) remains to be investigated.

Keywords:
toxicology, TLC, screening, analytical toxicology, temperature, relative humidity, climatic conditions

Paper ID: JFS13283J
DOI: 10.1520/JFS13283J
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