[Detection of opiates in the urine using thin-layer chromatography]

The determination of opiates in urine by thin layer chromatography may be difficult for the low concentrations of opiates and their mixtures. The result of the analysis is influenced by the isolation recovery, sensitivity of detection and by the choice of the chromatographic conditions for the separation of opiate mixtures. The study of these factors resulted in several modifications of routinely used method, so that the results are reliable for the concentration of opiates in urine 1 mg/l. Nevertheless, for the analysis of opiates in drug abuse control the comparison of thin layer chromatography findings with other chromatographic methods or immunoassays is important for the improvement of the laboratory performance and for the interpretation of the results.