J. Planar Chromatogr. 36, 257-263 (2023). HPTLC of ibuprofen on silica gel with acetic acid - ethyl acetate - n-hexane 5:24:71. Quantitative determination by absorbance measurement at 254 nm. Digital images were taken with a smartphone in a dark room under UV light. Image analysis was performed using the processing software Fiji. Linearity was in the range of 3-5 mg/mL. LOD and LOQ were 0.9 and 2.9 mg/mL, respectively. Mean recovery was 99.9 %.

J. Planar Chromatogr. 36, 251-256 (2023). HPTLC of paracetamol in plasma on silica gel with acetone - hexane - ammonia 40:50:1. Quantitative determination by absorbance measurement at 254 nm. The hRF value for stigmasterol was 33. Linearity was in the range of 80-180 μg/mL. Intermediate precisions were below 5 % (n=3). LOD and LOQ were 9 and 27 μg/mL, respectively. Recovery was between 99.6 and 106.8 %.

J. Planar Chromatogr. 36, 295-305 (2023). HPTLC of propyphenazone (1), caffeine (2) and ergotamine tartrate (3) in tablets and spiked human plasma on silica gel with methanol - ethyl acetate - glacial acetic acid 10:90:1. Quantitative determination by absorbance measurement at 210 nm. The hRF values for (1) to (3) were 84, 56 and 18, respectively. Linearity was in the range of 0.1-12 μg/zone for (1) and 0.1-10 μg/zone for (2) and (3). Intermediate precisions were below 2 % (n=3). Average recovery was 101.4 % for (1), 99.2 % for (2) and 101.1 % for (3).

J. Planar Chromatogr. 36, 307-313 (2023). HPTLC of erlotinib in bulk and tablet formulation on silica gel with ethyl acetate - toluene - glacial acetic acid 35:15:1. Quantitative determination by absorbance measurement at 246 nm. The hRF value for erlotinib was 39. Linearity was in the range of 200-800 ng/zone. Intermediate precisions were below 1 % (n=3). LOD and LOQ were 5 and 15 ng/zone, respectively. Average recovery was 100.1 %.

J. Planar Chromatogr. 36, 265-277 (2023). HPTLC of amlodipine besylate (1), metoprolol succinate (2) and telmisartan (3) in a synthetic mixture on silica gel with toluene - isopropanol - methanol - triethylamine 30:10:5:1. Quantitative determination by absorbance measurement at 233 nm. The hRF values for (1) to (3) were 48, 36 and 15, respectively. Linearity was in the range of 500-2500 ng/zone for (1), 400-2000 ng/zone for (2) and 100-500 ng/zone for (3). Intermediate precisions were below 2 % (n=6). LOD and LOQ were 51 and 154 ng/zone for (1), 161 and 488 ng/zone for (2) and 26 and 79 ng/zone for (3), respectively. Mean recovery was 98.9 % for (1), 99.4 % for (2) and 100.2 % for (3).

J. Planar Chromatogr. 36, 137-146 (2023). HPTLC of alfuzosin (1) and tadalafil (2) on silica gel with dichloromethane - toluene - methanol 7:1:2. Quantitative determination by absorbance measurement at 235 nm. The hRF values for (1) and (2) were 31 and 82, respectively. Linearity was in the range of 400-2400 ng/zone for (1) and 200-1200 ng/zone for (2). Intermediate precisions were below 2 % (n=3). LOD and LOQ were 21 and 63 ng/zone for (1) and 10 and 31 ng/zone for (2). Average recovery was 100.7 % for (1) and 99.6 % for (2).

Chinese J. Pharm. Research 42 (2), 98-104 (2023). Ganoderma lucidum is the dry fruiting body of fungus, a medicinal plant, having the effect of relieving asthma and relieving nerves. Ganoderma lucidum is widely distributed in China and mainly concentrated in Zhejiang, Anhui, Shandong, Jilin, and Fujian. In this study, the HPTLC method for quality detection and origin traceability was established towards the medicinal material produced in Fujian and other areas. HPTLC of the ethanol extracts of the sample materials on silica gel with chloroform – acetonitrile – methanol – formic acid 130:15:2:2, three times to distances of 3 cm, 6 cm, 8 cm. Detection by spraying with 3 % sulfuric acid in ethyl acetate and heating at 105°C until the bands are clearly visualized, evaluation at UV 366 nm. The bands on the thin layer chromatogram were identified by fingerprint comparison using standard samples, and cluster analysis for the data of samples from different producing areas was performed using digital characterization. As results, the HPTLC analysis detected 17 distinct bands and among them, 11 components were identified, e.g. ganoderenic acid C (hRf 0.31), ganoderic acid C2 (hRf 33), ganoderic acid l (hRf 35), ganoderic acid G (hRf 41), ganoderic acid A (hRf 44), ganoderic acid B (hRf 46), ganolactone B (hRf 53), 3β,7β,15β-trihydroxy-11,15-dihydroxy-lanostane-8-alkene-24→20 lactone (hRf 56), ganoderenic acid D (hRf 61), ganoderic acid D (hRf 63) and 20 (21)-dehydrolucidenic acid A (hRf 65). A total of 10 HPTLC bands were identified in Fujian Ganoderma lucidum, among which ganoderic acid C2, ganoderic acid D and two unknown component bands (hRf 14 and 17) were unique and could be used as markers of Fujian Ganoderma lucidum. Thus samples of Fujian Ganoderma lucidum can be differentiated from those of other areas, when the Euclidean distance is 25 in Euclidean cluster analysis.

J Chromatogr Sci, 61 (3), 269-278 (2023). Development of a method for identification, quantification and stability study of linalool in Homalomena aromatica Schott, a herb with anti-rheumatism, nourishing and strengthening effects, and for the treatment of stomach disease. HPTLC hyphenated with MS for linalool on silica gel with toluene - ethyl acetate 19:1. Detection  with p-anisaldehyde reagent. The hRf of linalool is 35, identification of linalool at m/z 137, (M + H)+ by using MS technique. Study of the stability of linalool by investigating the effect of acid, base, UV, sunlight, thermal stress and H2O2 on it, the highest effect was observed with acidic pH with a 65 % degradation. The content of linalool was 58 % in the volatile oil of H. aromatica.