J. Planar Chromatogr. 33, 457-462 (2020). HPTLC of scopoletin (1) and gallic acid (2) in the aerial parts of Jatropha glandulifera on silica gel with toluene - ethyl acetate - glacial acetic acid 75:25:1. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) and (2) were 69 and 40, respectively. Linearity was between 100 and 600 ng for (1) and (2). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 70 and 200 ng for (1) and 40 and 100 ng for (2), respectively. Recovery was between 98.8 and 98.9 % for (1) and 97.4 and 98.1 % for (2).

J. Planar Chromatogr. 33, 489-499 (2020). HPTLC of fructose (1), glucose (2) and sucrose (3) in honey on silica gel with 1-butanol-2-propanol - boric acid - water 3:5:1. Detection by spraying with 2 mL of aniline diphenylamine phosphoric acid reagent, followed by heating at 110 ºC for 10 min. The hRF values for (1) to (3) were 14, 32 and 27, respectively. Linearity was between 250 and 1250 ng/zone for (1) to (3). Intermediate precision was below 7 % (n=3). The LOD and LOQ were 22 and 67 ng for (1), 33 and 100 ng for (2) and 21 and 64 ng for (3), respectively. Average recovery was 100.7 % for (1), 101.4 % for (2) and 104.0 % for (3).

J. Planar Chromatogr. 33, 473-479 (2020). HPTLC of rutin (1), gallic acid (2) and quercetin (3) in the aerial parts of Euphorbia hirta and Euphorbia thymifolia on silica gel with toluene - ethyl acetate - methanol - formic acid 30:15:13:4. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) to (3) were 2, 56 and 72, respectively. Linearity was between 40 and 480 ng/zone for (1) to (3). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 15 and 45 ng/zone for (1), 45 and 139 ng/zone for (2) and 20 and 61 ng/zone for (3), respectively. Recovery ranged 98.3-100.2 % for (1), 98.5-99.6 % for (2) and 95.5-99.1 % for (3).

J. Planar Chromatogr. 33, 463-472 (2020). HPTLC of chlorogenic acid in the fruit extracts of Lufa acutangula, Sechium edule, Trichosanthes cucumerina and Trichosanthes dioica on silica gel with ethyl acetate - chloroform - formic acid 12:8:1. Quantitative determination by absorbance measurement at 254 nm. The hRF value for chlorogenic acid was 55. Linearity was between 200 and 1000 ng/zone. Intermediate precision was below 2 % (n=3). Recovery was between 99.7 and 99.9 %.

J. Planar Chromatogr. 33, 501-509 (2020). HPTLC of chloramphenicol (1), dexamethasone sodium phosphate (2) and tetrahydrozoline HCl (3) in the absence or presence of p-nitroacetophenone (4) on silica gel with ethanol - water - ammonia 14:5:1 (method A) and acetonitrile - water - ammonia 20:6:1 (method B). Quantitative determination by absorbance measurement at 242 and 220 nm. The hRF values for (1) to (3) were 76, 65 and 20, respectively, in method A and the hRF values for (1) to (4) were 78, 38, 58 and 87, respectively, in method B. Linearity was 0.1-1.4 µg/zone for (1), 0.2-1.2 µg/zone for (2) and 0.1-0.5 µg/zone for (3) in method A and 0.6-1.8 µg/zone for (1), 0.8-3.2 µg/zone for (2), 0.01-0.1 µg/zone for (3) and 0.3-1.4 µg/zone for (4) in method B. Intermediate precision was below 2 % (n=3). The LOD and LOQ were 30 and 90 ng/zone for (1), 40 and 120 ng/zone for (2) and 20 and 60 ng/zone for (3) in method A and 60 and 180 ng/zone for (1), 130 and 390 ng/zone for (2), 3 and 9 ng/zone for (3) and 70 and 210 ng/zone for (4) in method B. Average recovery was 100.1 % for (1), 100.2 % for (2), 100.6 % for (3) in method A and 100.1 % for (1), 99.9 % for (2) and 100.2 % for (3) in method B.

J. Planar Chromatogr. 33, 511-522 (2020). HPTLC of celecoxib (1) and diacerein (2) on nanosilica gel with n-hexane - ethyl acetate - tetrahydrofuran - glacial acetic acid 35:15:5:4. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) and (2) were 59 and 37, respectively. Linearity was between 20 and 320 ng/zone for (1) and 5 and 80 ng/zone for (2). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 7 and 20 ng/zone for (1) and 2 and 5 ng/zone for (2), respectively. Average recovery was 99.9 % for (1) and 99.6 % for (2).

J. Planar Chromatogr. 33, 381-390 (2020). HPTLC of riociguat in tablets on silica gel with ethyl acetate - methanol - glacial acetic acid 80:20:3. Quantitative determination by fluorescence measurement at 300/>465 nm. The hRF value for riociguat was 59. Linearity was between 5 and 25 ng/zone. Intermediate precision was below 2 % (n=3). The LOD and LOQ were 3.4 and 10.2 ng/zone, respectively. Recovery was between 98.7 and 99.1 %. The method was compared with spectrofluorimetric and UV-spectrophotometric methods.

J. Planar Chromatogr. 33, 353-364 (2020). HPTLC of friedelin (1), methylputranjate (2), putrone (3), roxburghonic acid (4), putranjivadione (5), and roxburghonol (6) in the bark of the plant Putranjiva roxburghii on silica gel with n-hexane - ethyl acetate 9:1. Detection by dipping into perchloric acid reagent (50 mL 70% perchloric acid in 50 mL acetone), followed by heating at 110-120 ºC for 5 min. Quantitative determination by absorbance measurement at 570 nm. The hRF values for (1) to (6) were 79, 46, 36, 31, 25 and 21, respectively. Linearity was between 1 and 5 µg/zone for (1) to (6). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 780 and 2600 ng/zone for (1), 210 and 700 ng/zone for (2), 170 and 570 ng/zone for (3), 350 and 1170 ng/zone for (4), 460 and 1530 ng/zone for (5) and 380 and 1270 ng/zone for (6), respectively. Average recovery was 98.0 % for (1), 99.1 % for (2), 97.6 % for (3), 98.9 % for (4), 98.7 % for both (5) and (6).