– a botanical source of the Ayurvedic drug Jivanti. J. Planar Chromatogr. 31, 150-154 (2018). HPTLC of β-sitosterol (1), lupeol (2), and oleanolic acid (3) in Leptadenia pyrotechnica with toluene – ethyl acetate 9:4 for (1); toluene – ethyl acetate – formic acid 70:30:3 for (2), and toluene – methanol – formic acid 45:20:1 for (3). Detection by spraying with freshly prepared p-anisaldehyde sulfuric acid reagent, followed by heating at 110 °C for 3 min. Quantitative determination by absorbance measurement at 530 and 540 nm. The hRf values for (1) to (3) were 64, 84 and 47, respectively. Linearity was in the range of 2-10 μg/zone for (1) to (3). The intermediate precision was below 0.6 %. The LOD and LOQ were 410 and 1270 ng/zone for (1), 550 and 1680 ng/zone for (2) and 300 and 920 ng/zone for (3), respectively. Average recovery for (1) to (3) was 99 %.

J. Chromatogr. Sci. 56, 317-326 (2018). Development of an accurate, sensitive and highly selective stability-indicating method for simultaneous determination of agomelatine (AGM) and its forced degradation products (Deg I and II) by HPTLC on silica gel with chloroform – methanol – ammonia 90:10:1. Quantitative determination by densitometry at 230 nm over the concentration range of 0.2-1.2 μg/band for AGM in pure form and human plasma, and 0.1-1 μg/band for both Deg I and II. The method was successfully applied for the analysis of AGM in pharmaceutical formulations. Statistical comparison of the results to those obtained by HPLC revealed its high accuracy and good precision.

J. Planar Chromatogr. 31, 318-326 (2018). HPTLC of quercetin (1), kaempferol (2), and keto-β-boswellic acid (3) in the herbal extracts of Spinacia oleracea and Boswellia serrata on silica gel with hexane ‒ ethyl acetate ‒ glacial acetic acid 30:20:1. Quantitative determination by absorbance measurement at 272 nm. The hRF values for (1) to (3) were 22, 40 and 54, respectively. Linearity ranged between 1500-3500 ng/zone for (1), 200-600 ng/zone for (2) and 1040-3120 ng/zone for (3). LOD and LOQ were 185 and 560 ng/zone for (1), 42 and 125 ng/zone for (2), and 324 and 981 ng/zone for (3), respectively. The intermediate precision was <2 % (n=3). Recovery ranged between 97 and 100 %.

J. Planar Chromatogr. 31, 421-428 (2018). HPTLC of solamargine in Solanum species on silica gel with dichloromethane ‒ methanol ‒ 2.5% aqueous ammonia 75:25:2. Detection by dipping into anisaldehyde sulfuric acid reagent, followed by heating at 110 °C. Quantitative determination by absorbance measurement at 540 nm. The hRF value for solamargine was 15. Linearity was between 25 and 300 ng/zone. LOD and LOQ were 1 and 4 ng/zone. The intermediate precision was <2 % (n=3). Average recovery was 101.2 %.

J. Planar Chromatogr. 31, 461-468 (2018). HPTLC of dabigatran etexilate mesylate on silica gel with methanol ‒ ethyl acetate ‒ benzene 3:4:4. Quantitative determination by absorbance measurement at 225 nm. The hRF value for dabigatran etexilate mesylate was 82. Linearity was between 0.3 and 3 μg/zone. LOD and LOQ were 0.03 and 0.09 μg/zone. The intermediate precision was <2 % (n=3). Average recovery was 98.9 %.

varieties by analytical OPLC. Proc. Intern. Symposium on TLC with special Emphasis on OPLC, Szeged, 46 (1984). OPLC (OPTLC) of trimethyl-L-lysine on silica with propanol - methanol - 0.l M sodium acetate in water 20:3:30. Detection with Dragendorff reagent. Densitometry by absorbance at 525 nm.

Acta Veterinaria 32, 97-101 (1984). TLC of monensin, nigericin on silica with chloroform - methanol 9:1. Spraying with vanillin - sulfuric acid solution, followed by heating at 800C for 5 minutes. Scanning by absorbance at 505 nm for monensin, at 510 nm for nigericin. Standard deviation + 0.8 - + 4 %.

Anal. Chem. 56, 1600-1603 (1984). HPTLC of gibberellins A3 and A4+A7 on silica with cyclohexane - acetone 4:5. Detection/quantification after exposure to concentrated hydrochloric acid for 30 minutes. Fluorescence scanning at 366 nm / > 400 nm.