J. Planar Chromatogr. 27, 409-415 (2014). TLC of propanolol enantiomers on silica gel impregnated with 15 nm gold nanoparticles (AuNPs) and 10.0 mM L-cysteine (L-cys) pH = 8.1, as first and second layer, respectively and developed with 10.0 mM copper(II) acetate, in 70% ethanol – water adjusted at pH 6.3.

leaves by high-performance thin-layer chromatography. J. Planar Chromatogr. 27, 357-361 (2014). HPTLC of (1) lawsone, (2) methylene-3,3'-bilawsone, and (3) lawsone methyl ether on silica gel with n-butyl acetate – chloroform – glacial acetic acid 60:40:1. Quantitative determination by absorbance measurement at 280 nm. The hRF values for (1) to (3) were 23, 15 and 36, respectively. Linearity was between 5 and 15 μg/zone for each substance. The intermediate intra-day and inter-day precisions were below 2 % (n=3). The LOD and LOQ were 200 and 600 ng/zone for (1) to (3), respectively.

J. Planar Chromatogr. 27, 392-397 (2014). HPTLC of (1) rifampicin, (2) isoniazid, and (3) pyrazinamide in a dosage tablet on silica gel with ethyl acetate – acetone – methanol – glacial acetic acid 18:5:5:2. Quantitative determination by absorbance measurement between 200 and 800 nm. The hRF values of (1) to (3) were 25, 44 and 74, respectively. Linearities were in the range of 250-600 ng/zone for (1), 125-300 ng/zone for (2) and 625-1500 ng/zone for (3). The intermediate precision was below 2.3 % (n=6) . Mean recoveries for (1) to (3) were 100.0, 98.6 and 99.4 %, respectively.

Heilongjiang Med. J. 26 (5), 746-750 (2013). Ganmaoling Jiaonang capsules are a TCM preparation composed of traditional Chinese herbal and Western drugs, with antipyretic and analgesic effects, which is used for headaches, fever, runny nose, sore throat, etc. For quality control, TLC on silica gel (1) for Evodia lepta (Spreng.) Merr with water-saturated toluene – ethyl acetate – formic acid 5:4:1, detection at UV 366 nm; (2) for Herba Bidentis bipinnate and Herba Bidentis pilosae with chloroform – methanol – formic acid 35:5:2, detection by (A) exposure to ammonia vapor and evaluation under white light and (B) spraying with 10 % sulfuric acid in ethanol and heating at 105 °C until the zones are visible; (3) for Ilex asprella (Hook. et Arn.) Champ. ex Benth. with benzene – acetone 9:1, detection at UV 366 nm. Quantitation of 4-acetamidophenol, chlorpheniramine maleate and caffeine by HPLC.

Chinese J. of Pharm. Research 33 (6), 328-331 (2014). Yinyanghuo Tongluo Wan pill is a TCM preparation for special treatment of diabetic peripheral neuropathy. For quality control, TLC on silica gel (1) for processed Epimedium and the standard icariin with ethyl acetate – butanone – formic acid 10:1:1:1, detection by spraying with 3 % aluminum trichloride in ethanol and heating mildly until the zones are visible at UV 366 nm; (2) for Panax ginseng C. A. Mey., ginsenoside Rb1, ginsenoside Re, and ginsenoside Rg1 with chloroform – methanol – water 13:7:2, detection by spraying with 10 % sulfuric acid in ethanol and heating at 105 °C until the zones are visible and at UV 366 nm; (3) for Ligusticum chuanxiong Hort. with cyclohexane - ethyl acetate 9:1, detection at UV 366 nm; (4) for Paeonia lactiflora Pall. and paeoniflorin with chloroform – methanol – ethyl acetate – concentrated ammonia 20:8:4:1, detection by spraying with 5 % vanillin in sulfuric acid – ethanol 1:4, followed by heating until the zones are visible; (5) for Atractylodes macrocephala Koidz. with petroleum ether (60-90 °C), detection by spraying with 5 % vanillin in sulfuric acid – ethanol 1:4, followed by heating until the zones are visible; (6) for Cassia twig with petroleum ether (60-90 °C) – ethyl acetate 17:3, detection by spraying with 5 % vanillin in sulfuric acid – ethanol 1:4, followed by heating at 105 °C until the zones are visible, and at UV 366 nm.

Anal. Sci. 31, 535-541 (2015). HPTLC of neochlorogenic acid (1), chlorogenic acid (2), cryptochlorogenic acid (3), caffeic acid (4), rutin (5), hyperin (6), isoquercetin (7), quercitrin (8) and quercetin (9) on silica gel with ethyl acetate - methanol - formic acid 15:1:2. Quantitative determination by absorbance measurement at 365 nm. The hRF values of (5), (6) and (8) were 14, 25 and 44. Linearity was in the range of 1.3-41.6 µg/mL for (1), 2.9-94.3 µg/mL for (2), 1.3-41.4 µg/mL for (3), 0.4-12.4 µg/mL for (4), 0.8-25.7 µg/mL for (5), 2.5-81.0 µg/mL for (6), 0.9-28.9 µg/mL for (7), 6.4-203.8 µg/mL for (8) and 0.7-23.5 µg/mL for (9). LOD and LOQ for (1) to (9) were in the range of 40-80 and 120-280 ng/mL, respectively. The intermediate/interday/intraday precision was 2.7 %. Recoveries for (1) to (9) ranged from 97 to 103 %.

and species comparison study using high-performance thin-layer chromatography - mass spectrometry. J. Planar Chromatogr. 28, 280-286 (2015). HPTLC of trichostachine (1), piperine (2), 4,5-DHPL (3), guineensine (4), pellitorine (5) and sesamin (6) in Piper longum, Piper chaba and Piper nigrum on silica gel with ethyl acetate - n-hexane - dimethyl amine 40:60:1. Quantitative determination by absorbance measurement at 273 nm for (4) and (5), 294 nm for (3) and (6) and 340 nm for (1) and (2). The method was coupled with MS to identify the 6 markers. The hRF values for (1) to (6) were 12, 36, 46, 71, 78 and 82, respectively. Linearity was in the range of 25-1000 ng/zone for (1) to (6). LOD was between 4 and 7 ng/zone whereas LOQ was between 14 and 20 ng/zone for (1) to (6). The intermediate precision was below 1 % (n=4). Recoveries were in the range of 99-103 %.

J. Planar Chromatogr. 28, 452-457 (2015). HPTLC of caffeic acid (1), vanillic acid (2), syringic acid (3) and kaempferol (4) in flowers and flower buds of Bauhinia purpurea L., Bauhinia variegata L., and Bauhinia acuminata L. on silica gel with toluene - ethyl acetate - formic acid 5:4:1. Quantitative determination by absorbance measurement at 350 nm. The hRF values for (1) to (4) were 54, 61, 57 and 64. Linearity was in the range of 100-700 ng/zone for (1) to (4). LOD and LOQ were 40 and 100 ng/zone for all four substances. The intermediate precision was below 1.8 % (n=3). Recovery ranged from 97-99 % for (1), 97-100 % for (2), 99-100 % for (3) and 98-99 % for (4).