J. Planar Chromatogr. 34, 427-435 (2021). HPTLC of phyllanthin (1) and hypophyllanthin (2) in Phyllanthus amarus on silica gel with toluene - ethyl acetate 17:3. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) and (2) were 21 and 35, respectively. Linearity was between 2 ans 7 μg/zone for (1) and (2). LOD and LOQ were 1 and 3 μg/zone for (1) and (2), respectively. Intermediate precisions were below 2 % (n=3).

J. Planar Chromatogr. 34, 437-446 (2021). HPTLC of phenolic compounds in the leaf extract of Costus pictus on silica gel with chloroform - glacial acetic acid - methanol - water 16:8:3:2. Compounds with the same hRF values were analyzed by high-performance liquid chromatography, diode array detector and tandem mass spectrometry.

J. Planar Chromatogr. 34, 323-328 (2021). HPTLC of plumbagin in the roots of Plumbago zeylanica on silica gel with toluene - ethyl acetate 9:2. Quantitative determination by absorbance measurement at 270 nm. The hRF value for plumbagin was 84. Linearity was between 100 and 600 ng/zone. LOD and LOQ were 70 and 200 ng/zone, respectively. Intermediate precisions were below 2 % (n=3). Average recovery was 98.8 %.

J. Planar Chromatogr. 34, 297-305 (2021). HPTLC of four kinds of hydroxynaphthoquinone ingredients, namely β-hydroxyisovaleryl shikonin (1), L-shikonin (2), β-acetoxyisovaleryl shikonin (3), and acetyl shikonin (4) in the roots of Arnebia euchroma on silica gel with cyclohexane - dichloromethane - ethyl acetate - formic acid 50:90:6:11. Quantitative determination by absorbance measurement at 520 nm. The hRF values for (1) to (4) were 20, 30, 50 and 60, respectively. Linearity was between 56 and 678 ng/zone for (1), 64 and 768 ng/zone for (2), 132 and 1590 ng/zone for (3) and 253 and 3042 ng/zone for (4). Intermediate precisions were below 3 % (n=3). Average recovery was 99.5 % for (1), 100.6 % for (2), 98.6 % for (3) and 97.0 % for (4).

J. Food Sci. 85, 1781-1792 (2020). HPTLC of scented (joha) rice and black rice variety on silica gel with chloroform - methanol 19:1 + 0.1 % formic acid and butanol - acetic acid - water 4:1:5. Detection by spraying with p-anisaldehyde and visualization under UV light at 200, 250 and 350 nm. The husk of the selected rice varieties contained the nonpolar metabolites whereas the seeds contain nonpolar as well as polar metabolites.

J. Ethnopharmacol. 275, 114054 (2021). HPTLC of ellagic acid in Anogeissus latifolia on silica gel with toluene - ethyl acetate - formic acid 20:5:1. Detection by spraying with anisaldehyde - sulphuric acid reagent, followed by heating at 105 °C. The hRF value for ellagic acid was 38.

Phytochem. Anal. 3093 (2021). HPTLC of hyperforin (1), hypericin (2) and hyperoside (3) in Hypericum species on silica gel with n-hexane - ethyl acetate 4:1 for (1), toluene - chloroform - ethyl acetate - formic acid 80:50:35:6 for (2) and ethyl acetate - formic acid - acetic acid - water 15:2:2:1 for (3). Detection by spraying with a derivatizing reagent (20 mL of sulfuric acid were carefully added to 120 mL methanol and diluted with 200 mL methanol), followed by heating. Quantitative determination by absorbance measurement at 366 nm. The hRF values of (1) to (3) were 49, 35 ad 49, respectively. Linearity was between 0.4 and 1.4 µg/zone for (1), 20 and 100 ng/zone for (2) and 10 and 100 ng /zone for (3). The intermediate precision was below 2 % (n=6) for (1) to (3). The LOD and LOQ were 120 and 400 ng/zone for (1), 6 and 20 ng/zone for (2) and 3 and 10 ng/zone for (3), respectively. Recovery was between 101.0 and 101.2 % for (1), 98.8 and 100.1 % for (2) and 100.4 and 101.4 % for (3).

Phytochem. Anal. 33, 83-93 (2022). HPTLC of table olives (Olea europaea) on silica gel with dichloromethane - methanol - acetic acid 45:5:1. Detection by spraying with sulfuric vanillin reagent (5 % vanillin in methanol - 5 % sulfuric acid in methanol 1:1) and under UV light at 254 and 366 nm. Further analysis by nuclear magnetic resonance.