J. Ethnopharmacol. 193, 627-636 (2016). HPTLC of hyperoside (1), rutoside (2), apigenin (3), spiraeoside (4), quercetin (5), and isoquercitrin (6) on silica gel with ethyl acetate – formic acid – glacial acetic acid – water 100:11:11:26. Detection by spraying with natural product/PEG reagent, followed by drying for 10 min. Quantitative determination by absorbance measurement at 366 nm. The hRF values for (1) to (6) were 55, 37, 95, 6, 92 and 57, respectively._x000D_

Innov. Food Sci. Emerg. Technol. 37, 184-191 (2016). HPTLC of aflatoxin B1 in Aspergillus flavus isolates on silica gel with toluene – isoamyl alcohol – methanol 90:32:2. Qualitative determination under UV light at 360 nm.

J. Liq. Chromatogr. Relat. Technol. 40, 239-246 (2017). Review of TLC methods for the analysis of polyphenols, dyes, carboxylic acids, biogenic amines, and vitamin C in quality assessment and authentication of non-fermented or fermented beverages derived from fruits.

J. Planar Chromatogr. 30, 264-270 (2017). HPTLC of quercetin (1), apigenin (2) and kaempferol (3) in the stem bark of C. macleodii, C. rothi and C. dichotoma on silica gel with toluene ‒ ethyl acetate ‒ glacial acetic acid ‒ formic acid 10:10:1:2. Quantitative determination at UV 254 nm. The hRF values for (1) to (3) were 64, 66 and 71. LOD and LOQ were 9 and 29 ng/zone for (1), 30 and 92 ng/zone for (2) and 57 and 173 ng/zone for (3), respectively. The intermediate precision (n=6) was below 2 % for (1) and (2).

J. Liq. Chromatogr. Relat. Technol. 40, 22-286 (2017). HPTLC of clarithromycin (1), azithromycin (2), and amodiaquine (3) and artesunate (4) on silica gel with methanol – ethyl acetate – concentrated ammonium hydroxide 40:10:1 for (1) and (2) and acetone – water – concentrated ammonium hydroxide 40:7:2 for (3) and (4). Detection by heating for 15 and 30 min, respectively, for (1) and (2) at 160 °C to activate fluorescence quenching. Naturally fluorescence quenching zones of (3) were scanned at 254 nm and (4) after heating the plate for 5 min at 180 °C to activate fluorescence quenching.

J. Chromatogr. Sci. 54 (7), 1096-1104 (2016). TLC of the extracts of the dried aerial parts of 12 plants of Cirsium species and five selected standards (naringin, apigenin, rutin, caffeic acid and chlorogenic acid) on silica gel with ethyl acetate – formic acid – acetic acid – water 24:3:3:8 on RP-18 phase with 5 % aqueous solution of formic acid – methanol 7:3 for the first development and the same system in the ratio of 1:1 for the second development. Analysis of the results by chemometrics. The comparison of individual Cirsium species and the identification of unknown species by using the similarity indices (Pearson's correlation coefficient, determination coefficient and congruence coefficient), distance indices (Euclidean distance, Manhattan distance and Chebyshev's distance) and Multi-Scale Structural SIMilarity. Based on chemometric analysis, the first extract of the widely grown species is identified as Cirsium arvense and the second one as Cirsium rivulare.

J. Planar Chromatogr. 30, 502-509 (2017). HPTLC of chlorogenic acid (1), gallic acid (2), caffeic acid (3), quercetin (4), p-coumaric acid (5) and kaempferol (6) in the fresh leaves, flowers, pods, and dried pods and seeds of M. oleifera on silica gel with toluene – ethyl acetate – formic acid 14:10:1. Quantitative determination by absorbance measurement at 282 nm. The hRF values for (1) to (6) were 1, 31, 41, 45, 49 and 52, respectively. Linearity was between 0.1 and 1.5 μg/zone for (1) to (6). LOD and LOQ were 142 and 382 ng/μL for (1), 126 and 343 ng/μL for (2), 114 and 410 ng/μL for (3), 116 and 301 ng/μL for (4), 125 and 356 ng/μL for (5) and 110 and 345 ng/μL for (6), respectively. The intermediate precision was <3 % (n=6). Average recovery was 96.2 % for (1), 97.9 % for (2), 97.3 % for (3), 96.5 % for (4), 97.1 % for (5) and 96.2 % for (6).

J. AOAC Int. 99, 1204-1212 (2016). HPTLC of St. John’s wort labeled as Hypericum perforatum on silica gel with ethyl acetate – dichloromethane – formic acid – acetic acid – water 100:25:10:10:11 (USP 38-NF33), ethyl acetate – formic acid – water 30:2:3 (European Pharmacopoeia) and ethyl acetate – acetic acid – formic acid – water 100:11:11:26 (USP 37-NF32). For the investigation of synthetic dyes, samples were analyzed on RP-18 with methanol – 5 % aqueous sodium sulfate 3:4. Detection by dipping into natural products reagent (1 g diphenylborinic acid 2-aminoethylester in 200 mL ethyl acetate), then in polyethylene glycol reagent (10 g PEG 400 (macrogol) in 200 mL dichloromethane). Qualitative identification under UV 254 and 366 nm. A decision tree was developed to analyze adulterated samples labeled as Hypericum perforatum. If for example under UV 366 nm after derivatization a yellow fluorescent zone is seen at hRF 46, samples are probably mixed with another undesired species. In addition, if a bluish zone is seen at application position of samples identified with the test USP 38-NF32 and examined under white light prior derivatization, the sample is probably mixed with dyes.