J. Planar Chromatogr. 26, 260-266 (2013). HPTLC of of iridoids 10-O-trans-p-coumaroylcatalpol (1), 4-hydroxy-E-globularinin (2) and premnosidic acid (3) in the stem bark of Premna integrifolia on silica gel with ethyl acetate - methanol - water - acetic acid 40:6:3:1. Detection by dipping into vanillin - sulphuric acid reagent (1 % vanillin in ethanol - sulfuric acid 19:1), followed by heating at 110 ºC for 3 min. Quantification by absorbance measurement at 510 nm. The hRf values for (1) to (3) were 52, 41 and 33, respectively. Linearity was in the range of 1-10 µg/zone for (1) to (3). LOD and LOQ were 198 and 663 ng/zone for (1), 312 and 1040 ng/zone for (2) and 200 and 666 ng/zone for (3), respectively. Average recoveries for (1) to (3) were found to be 97.3 %, 98.3 % and 97.6 %, respectively. Intermediate/interday/intra-day precision was below 2 % (n=9).

J. Planar Chromatogr. 26, 215-225 (2013). HPTLC of gatifloxacin and 8 related substances on silica gel with methanol - 1,2-dichloroethane - ammonia - acetonitrile 28:72:5:5. Quantitative determination by absorbance measurement at 366 nm. The hRf value for gatifloxacin was 42. Linearity was in the range of 20-1000 ng/zone. LOD and LOQ were 2.6 and 5.6 ng/zone. Intermediate/interday/intra-day precision was below 2 % (n=6). The method showed comparable results with a validated RP-HPLC mehod.

J. Planar Chromatogr. 26, 312-315 (2013). HPTLC of L-dopa (1) and rutin (2) in a polyherbal formulation on silica gel with butan-1-ol - acetic acid - water 4:1:1 for (1) and ethyl acetate - butan-1-ol - formic acid - water 5:3:1:1 for (2). Quantification by absorbance measurement at 288 nm for (1) and 254 nm for (2). The hRf values for compounds (1) and (2) were 45 and 50, respectively. Linearity was in the range of 0.4-1.2 µg/zone for (1) and 0.4-0.9 µg/zone for (2). LOD and LOQ were 64 and 159 ng/zone for (1) and 76 and 228 ng/zone for (2), respectively. Average recoveries were 99.6 % for (1) and 100.1 % for (2). Intermediate/interday/intra-day precision was below 5 % (n=8).

J. Planar Chromatogr. 27, 240-244 (2014). HPTLC of sulfide ions derivatized with 4-[p-,Ndimethylamino) phenyl]-2,6-diphenylpyrylium cations (25 μmol) in acetonitrile) on silica gel with a mixture of phosphoric buffer (pH 3.0) - propan-2-ol - acetonitrile 8:8:1. Quantitative determination by scanning and image analysis. The hRF values for thyopyrylium and the derivatization reagent were 73 and 54, respectively. Linearity was in the range of 40-500 pmol/zone. The intermediate/interday/intra-day precisions were below 2 % (n=9). The LOD and LOQ were 11 and 33 pmol/zone, respectively. Recovery was between 98 and 108 %.

J. Planar Chromatogr. 27, 157-161 (2014). HPTLC of withanoside V (1), withaferine A (2), 1,2-deoxywithastramonolide (3), withanone (4), withanolide A (5), and withanolide B (6) on silica gel with dichloromethane - toluene - methanol - acetone - diethyl ether 13:14:8:3:1. Quantitative determination by absorbance measurement at 235 nm. The hRF values for (1) to (6) were 7, 55, 61, 63, 66 and 77, respectively. Precision was below 2 % (n=3). The LOD and LOQ were 60 and 250 ng/zone for (1), 120 and 350 ng/zone for (2), 80 and 300 ng/zone for (3), (4) and (6), and 60 and 250 ng/zone for (5), respectively. Average recoveries for (1) to (6) were 97, 98, 99, 98, 98 and 99 %, respectively.

J. Planar Chromatogr. 27, 2980-2988 (2014). HPTLC of piperine in commercial samples of pepper on silica gel with acetone - n-hexane 3:2. Quantitative determination by absorbance measurement at 360 nm. The hRF value for piperine was 90. The LODs and LOQs were 590 and 1800 ng/zone, respectively. Recoveries were between 98.1 and 99.2 %

J. Planar Chromatogr. 27, 294-298 (2014). HPTLC of amiloride hydrochloride (1) and torsemide (2) in dosage forms on silica gel with chloroform - methanol - ammonia 15:7:2. Quantitative determination by absorbance measurement at 286 nm. The hRF values for (1) and (2) were 46 and 24, respectively. Linearity was in the range of 50-300 ng/zone for (1) and 100-600 ng/zone for (2). The intermediate/inter-day/intra-day precision were below 4 % (n=3). The LOD and LOQ were 16 and 50 ng/zone for (1) and 33 and 100 ng/zone for (2), respectively. Recoveries for (1) and (2) were between 97.4 and 99.5 %.

CBS 111, 7-9 (2013). HPTLC of benzophenone-3 (BP-3), butyl methoxydibenzoyl-_x000D_methane (BM-DBM), 3-benzylidene camphor (3‑BC), 4‑methylbenzylidene camphor (4‑MBC), octocrylene (OCR), ethylhexyl methoxycinnamate (EHMC), ethyl-hexyl salicylate (EHS), diethylhexyl butamido triazone (DEBT), octyldimethyl p-aminobenzoic acid (OD-PABA), 2-hydroxy-4-methoxy-benzophenone-5-sulfonic acid (HMBS), ethylhexyl triazone (EHT) on amino phase with petroleum ether - t-butyl-methyl ether - methanol 7:2:1 and 1 % triethylamine (HMBS with methanol – acetic acid 9:1), migration distance max. 48 mm from lower edge. For reaction with the UV filters the plate was stored up to 2 h in a dark at room temperature, then heated to 33 °C, and irradiated under natural sunlight or with a Suntest CPS+ at 350 W/m2. Quantitative absorbance measurement at UV 254 nm. The UV filters known as common triggers for photoallergic reactions showed the greatest tendency to bond to the amino phase. Thus, the developed screening method is well suited to estimate the potential of_x000D_ different UV filters to form protein adducts and to identify possible skin sensitizers.