(Arzneimittelfälschungen). Dtsch. Apoth. Ztg. 140, 63-70 (2000). TLC of anabolic steroid hormones (i. a. metandienone, stanozolol, methyltestosterone, clenbuterol hydrochloride) on silica gel with ethyl acetate - n-hexane 1:1. Evaluation under UV at 254 nm. Detection by spraying with 25 % sulfuric acid in ethanol and heating for 10 min at 1208C until optimum development of the colors of the spots. Simple and fast method.

J. Planar Chromatogr. 25, 108-111 (2012). HPTLC of indole acetic acid (1), indole butyric acid (2), and absisic acid (3) in watermelon seeds exposed to heavy metals on silica gel with cyclohexane - methanol - 2-propanol 4:2:1 +1 drop ammonia. Quantitative determination by absorbance measurement at 230 nm. Limit of quantification was 10 ng/zone for (1) and (2) and 6 ng/zone for (3).

I. Classification procedure by thin-layer chromatography.) Classification of pesticides, hypnotics, psychotropics, narcotics, local anesthetics etc. by their Rf values related to standard markers on silica TLC. The standard markers used: methyl yellow, methyl red, tetrabromophenol phthalein ethyl ester, malachite green and rhodamine B.

Chinese J. Chromatogr. (Sepu) 9, 113-116 (1991). TLC on silica with isopropanol - acetic acid - water 14:1:5. Detection by dipping into a solution of potassium hydroxide in ethanol and heating at 160 °C for 10 min. Quantification of fluoro densitometry at 230 nm. Detection limit 40 ng. The calibration curve was linear over the range of 40 - 350 ng with the correlation coefficient of 0.998.

Part 3. Identification of drugs and their metabolites by PCA of standardized TLC data. J. Planar Chromatogr. 7, 233-241, (1994). Principal components analysis of standardized Rf values of 443 drugs and their metabolites chromatographed with four eluent systems provided a two-component model accounting for 70.8% of the total variance. The "scores" plot enabled either identification, or restriction of the range of inquiry to few candidates. This simple, cheap and fast analytical method is of vital importance in the identification of an unknown drug in cases of overdose intoxication or poisoning, and is particularly valuable in the unaided search for drugs and their metabolites in instances when the substance is very polar and cannot be identified by gas chromatography.

Proc. 9th Internat. Symp. Instr. Chromatogr., Interlaken, April 9.-11., 155-159 (1997). HPTLC of D/L- methadone and L-methadone on diol with toluene - hexane - diethylamine 3:6:1. Detection by derivatization with modified Dragendorff reagent; quantification by densitometry at 254 nm.

J. Chromatogr. B 751 (1), 19-27 (2001). TLC on silica gel with hexane - toluene - diethylamine 13:4:1. Quantitation by densitometry at 234 nm. Evaluation of the accuracy, precision, detection and quantitation limits of the methods by comparison with HPLC.

J. Ethnopharmacol. 158, 454-457 (2014). The authors described how the European Pharmacopoeia provides a legal and scientific reference for the quality control of medicines. The document highlighted HPTLC as a tool for the screening of herbal drugs containing certain contaminants, such as aristolochic acids._x000D_