J. Chil. Chem. Soc. 58, 1737-1740 (2013). HPTLC of enalapril maleate in tablets on silica gel with 1-buthanol - glacial acetic acid - water 12:3:5. Quantitative determination by absorbance measurement at 207 nm. The hRf values of enalapril and its degradation products enalapril diketopiperazine and enalaprilat were 62, 82 and 52, respectively. Linearity was in the range of 200-1200 ng/zone for enalapril. LOD and LOQ were 23 and 72 ng/zone. Intermediate intra- and inter-day precision was below 2 % (n=6).

J. Liq. Chromatogr. Relat. Technol. 37, 61-72 (2014). HPTLC of khellin in the fruits of Ammi visnaga on silica gel with chloroform - acetone 9:1. Quantitative determination by absorbance measurement at 248 nm. The hRf of khellin was 29. Linearity was between 50 and 300 ng/zone. LOD and LOQ were 10 and 25 ng/mL. Recovery (by standard addition) was in the range of 98-99 %. Intermediate intra- and inter-day precision was below 1.6 % (n=6). The results obtained were comparable with HPLC results.

J. Planar Chromatogr. 26, 427-434 (2013). HPTLC of oseltamivir (1) in pharmaceuticals counterfeited with ascorbic acid (2) on silica gel with methanol - water 3:2 +1 drop ammonia. Quantitative determination by absorbance measurement at 254 nm. The hRf values for (1) and (2) were 70 and 83, respectively. Linearity was between 5 and 14 µg/zone. LOD and LOQ were 2 and 5 µg/zone. Average recovery (by standard addition) was found to be 100.6 %. Intermediate intra- and inter-day precision was below 1.6 %. Comparing with colorimetric method, HPTLC method provided advantages in terms of speed, lower cost, and environmental protection without sacrificing accuracy.

J. Planar Chromatogr. 27, 260-266 (2014). HPTLC of cichoric acid (1), chlorogenic acid (2) and echinacoside (3) in commercial Echinacea products on silica gel with ethyl acetate - formic acid - acetic acid - water 100:11:11:17. Quantitative determination by absorbance measurement at 254 and 366 nm. The hRF values for (1) to (3) were 80, 50 and 32, respectively. Linearity was in the range of 500-3500 ng/zone for (1), 100-700 ng/zone for (2) and 200-1200 ng/zone for (3). The intermediate/interday/intra-day precisions were between 4-12 % (n=3). The LOD and LOQ were 300 and 600 ng/zone for (1), 20 and 60 ng/zone for (2) and 98 and 123 ng/zone for (3), respectively.

J. Planar Chromatogr. 27, 140-144 (2014). HPTLC of andrographolide (1), neoandrographolide (2) and deoxyandrographiside (3) in the aerial parts of Andrographis paniculata on silica gel with dichloromethane - toluene - ethanol 13:5:3. Detection by dipping into p-anisaldehyde–sulfuric acid reagent, followed by heating at 110 ºC for 6 min. For quantification, image analysis with an office scanner at 200 dpi and densitometric measurement in absorbance mode at 540 nm. The hRF values for (1) to (3) were 61, 35 and 16, respectively. Linearity was in the range of 3-24 μg/zone for (1) and 1-8 μg/zone for (2) and (3). The intermediate/interday/intra-day precisions were below 3 % (n=3). The LOD and LOQ were 510 and 1700 ng/zone for (1), 140 and 480 ng/zone for (2) and 6 and 190 ng/zone for (3), respectively. Recovery was between 96.1 and 104.3 % for (1) to (3). Comparable results were obtained with the TLC-image analysis method, TLC-densitomety and HPLC.

J. Planar Chromatogr. 27, 107-112 (2014). HPTLC of disulfiram on RP-18 with methanol - water 9:1. Detection by spraying with copper(II) sulfate (0.5 mol/L), followed by heating at 50 ºC for 2 min. Quantitative evaluation with an office scanner at 300 dpi followed by image processing with software. The hRf value for disulfiram was 67. Linearity was in the range of 1-10 μg/zone. The intermediate/interday/intra-day precisions were below 1 % (n=6). The LOD and LOQ were 260 and 860 ng/zone, respectively. Recovery was in the range of 92.4-102.0 %.

J. Planar Chromatogr. 27, 5-10 (2014). _x000D_HPTLC of magnolol (1) and konokiol (2) in the cortex of Magnoliae officinalis on silica gel with toluene - methanol 10:1. Detection by dipping into 2,2-diphenyl-1-picrylhydrazyl radical reagent (DPPH) in ethanol (1 g/L) for 40 min. Quantitative determination by absorbance measurement at 550 nm. Linearity was in the range of 160-960 ng/zone for (1) and 162-977 ng/zone for (2). The intermediate/interday/intra-day precisions were below 2 % (n=6). The LOD and LOQ were 40 and 149 ng for (1) and 32 and 85 ng for (2), respectively. Recovery was in the range of 94.5-105.9 % for (1) and 86.6-103.4 % for (2). The HPTLC-DPPH method showed comparable results to an HPLC method._x000D_

J. of China Pharm. 27 (7), 722-724 (2013). Xihuang Wan pill is a herbal TCM prescribed for treatment and adjuvant therapy of various cancers. Huoxue Zhitong San powder is a herbal TCM prescribed for traumatic injury and ecchymoma. In the drug market fraud rosin was found to be added to the key ingredient olibanum. For quality control, HPTLC of the sample extracts and the standards acetyl-11-keto-beta-boswellic acid (AKBA), 11-keto-beta-boswellic acid (KBA), beta-boswellic acid (beta-BA), acetyl-beta-boswellic acid (beta-ABA), and abietic acid (LOD=1.0 µg), on silica gel with toluene – ethyl acetate – heptane – formic acid 80:20:10:3 with chamber saturation for 20 min, detection 1) under UV 254 nm and UV 366 nm; 2) by spraying with a fresh solution of anisaldehyde – sulfuric acid – acetic acid 1:10:1000 and heating at 105 °C until the zones were visible in daylight. Verification of abietic acid from added rosin by HPLC. The method was used for the analysis of 63 batches of Xihuang Wan pills sampled from 13 pharmaceutical factories and 10 batches of Huoxue Zhitong San powder from 4 factories.