J. Chromatogr. Sci. 54 (4), 647-652 (2016). Presentation of a sensitive, accurate and selective method for the simultaneous determination of paracetamol (PAR), its toxic impurity 4-aminophenol (4-AP), pseudoephedrine HCl (PSH) and loratidine (LOR). HPTLC on silica gel with acetone – hexane – ammonia 40:50:1. Densitometric evaluation at 254 nm for PAR, 4-AP and LOR, and at 208 nm for PSH. The method was used for the determination of PAR, PSH and LOR in commercial tablets and in plasma in the ranges of 0.5–6.0 µg/zone, 1.6–12.0 µg/zone and 0.4–2.0 µg/zone for PAR, PSH and LOR, respectively. Comparison of the results obtained by the proposed method with those obtained by HPLC method showed no significance difference between both methods regarding accuracy and precision.

J. Planar Chromatogr. 31, 389-395 (2018). HPTLC of paracetamol (1), pamabrom (2), and pyrilamine maleate (3) on silica gel with chloroform ‒ acetonitrile 3:7. Quantitative determination by absorbance measurement at 275 nm. The hRF values for (1) to (3) were 76, 46 and 12, respectively. Linearity ranged between 10-280 ng/zone for (1), 5-45 ng/zone for (2) and 1-20 ng/zone for (3). The intermediate precision was <2 % (n=3). The recovery was between 99.2 and 100.4 %.

(Thin-layer chromatography and high pressure liquid chromatography in mycotoxin analysis.) Z. Lebensm. Unters. Forsch. 178, 79-80 (l984). TLC and HPTLC methods support each other; the TLC method is preferred when the samples to be analyzed are of variable origin while HPLC is attractive when samples are uniform or at least similar.

J. Chromatogr. 351, 363-365 (1986). TLC of the diastereomeric D and L forms of hydroxylated fatty acids, whose hydroxyl and carboxylic groups are close together, on silicone-bonded silica with heptane - methyl formate- ether - acetic acid 50:40:10:2. Detection by spraying with 2 % molybdic acid in ethanol. Comparison with capillary GC method.

(Biological-physiological procedures of detection in thin-layer-chromatography procedures after manual transfer.) GIT-Suppl. 3, 79-87 (1986). Survey of indirect detection methods using bio-detectors, which are often more sensitive than known chemical reactions. Application for the detection of substances with antibiotics activity. Active plant hormones, pesticides, mycotoxins and compounds with cytostatic activity. Useful technique: Place developed plate on agar or gelatine sheet containing the antibiotic allyactive compound.

Chromatographia 27, 617-621 (1989). Evaluation of the florisil clean-up procedure for its suitability of quantifying aflatoxin in sorghum grain by bi-directional HPTLC. Investigation of the accuracy and precision of the method. Detec tion limits, 0.13˜0.36 µg/kg. Comparison with the AOAC CB method.

J. Planar Chromatogr. 2, 106-118 (1989). Comparison of methods. Review with 134 references discussing all kinds of planar separation techniques including TLC, HPTLC, and various kinds of electrophoresis. TLC and HPTLC coupled with different detection techniques such as radio detection and spectrophotometry are discussed. In general, planar chromatographic techniques are more rapid than column chromatographic techniques and have similar sensitivity and reproducibility. HPTLC has been applied to a very limited extent, but holds great promises for quantitative analysis. For molecules larger than MW 10’000, electrophoresis is considered the method of choice.

J. Chinese Herb Med. (Zhongcaoyao) 21, 203-205 (1990). TLC of berberine on silica with a) butanol – water – acetic acid 7:2:1, b) benzene – ethyl acetate – propanol – methanol – 70% ethylamine 16:8:4:1:1. Comparison of the results with those obtained by HPLC.