J. Planar Chromatogr. 25, 420-425 (2012). HPTLC of juglone (1), quercetin (2), myricetin (3), rutin (4), caffeic acid (5), and gallic acid (6) in the stem bark of Juglans regia L. on RP-18 with methanol - water - formic acid - acetic acid 61:58:3:3. Quantitative determination by absorbance measurement at 254 nm. The hRf values of compounds (1) to (6) were 16, 20, 31, 42, 55 and 78, respectively. Linearity was in the range of 13-800 ng/zone for (1) and (5), 100-1000 ng/zone for (2) and (6) and 50-800 ng/zone for (3) and (4). Limits of detection and quantification were 4 and 13 ng/zone for (1) and (5), 30 and 100 ng/zone for (2), 15 and 50 ng/zone for (3), (4) and (5), respectively. The intra-day and inter-day precisions for compounds (1) to (6) were in the range of 0.6-1.3 % and 0.5-1.9 %, respectively. Average recovery was between 98.6 and 101.1 %.

J. Liq. Chromatogr. Relat. Technol. 35, 1429-1443 (2012). Comprehensive HPTLC profiling of sugars, sugar alcohols, amino acids, flavonoids, and phenolic acids as well as further bioactive and antioxidative compounds in the Indian natural efficiency enhancer herbs Hippophae rhamnoides, Valeriana wallichii, Triticum aestivum, and fungus Cordyceps sinensis. HPTLC on silica gel with different mobile phases: for sugars, n-butanol–- isopropanol – acetic acid – boric acid solution 6:14:1:3, for amino acids, n-butanol – ammonia (25%) – pyridine – water 39:10:34:26, and for sugar alcohols, ethanol – ethyl acetate – water 7:2:1. Quantitative determination of sugars by absorbance measurement at 370 nm after derivatization with aniline diphenylamine o-phosphoric acid reagent (mixture of 70 mL aniline solution and 70 mL diphenylamine solution, 2 % in acetone each, and 10 mL o-phosphoric acid, 85%). Unknown marker compounds were characterized by HPTLC-attenuated total reflection fourier transform infrared spectroscopy (HPTLC-ATR FTIR) and HPTLC- electrospray ionization mass spectrometry (HPTLC-ESI-MS).

J. Planar Chromatogr. 25, 301-305 (2012). HPTLC of kaempferol (1) and apigenin (2) in the whole-plant powder of Sida spinosa Linn. on silica gel with dichloromethane - methanol - formic acid 16:2:1. Quantitative determination by absorbance measurement at 340 nm. Linearity was in the range of 150-450 µg/mL for (1) and 50-150 µg/mL for (2). The intermediate/inter-day/intra-day precision was below 2 %. Recovery was 99.5 % for (1) and 99.3 % for (2).

CBS 110, 2-4 (2013). HPTLC of caffeic acid, chlorogenic acid, and rutin hydrate on silica gel (prewashed with methanol and dried under vacuum at 50 °C for 30 min) with formic acid - ethyl acetate - water - methyl ethyl ketone 5:30:6:18 with chamber saturation for 5 min over a developing distance of 5 cm. Detection under UV 254 nm. Elution of substance zones with TLC-MS Interface using methanol and a flow-rate of 0.3 mL/min for 6 min. Evaporation of methanol under nitrogen, residue taken up with methanol-d4. Subsequent off-line quantitative 1H-NMR spectroscopic analysis of the residue, acquisition time 30 min. Linearity for all substances was confirmed in the range of 10 - 80 µg/mL. Recoveries were in the range of 100.5 % for chlorogenic acid and up to 103.4 % for caffeic acid, with precisions under 3.9 % (%RSD, n=3).

J. Planar Chromatogr. 26, 14-20 (2013). HPTLC of permethrin on silica gel with hexane - diethylether - ethyl acetate 22:2:1. Quantitative determination by absorbance measurement at 227 nm. The hRf values of cis- and trans-permethrin were 72 and 62, respectively. Linearity was in the range of 300-1800 ng/zone. LOD of cis- and trans-permethrin was 1.6 and 2.4 ng/zone, respectively. LOQ was 4.9 and 7.4 ng/zone for cis- and trans-permethrin, respectively. Intermediate precision was below 2 %.

J. Liq. Chromatogr. Relat. Technol. 36, 700-716 (2013). HPTLC of sertraline in bulk and formulation on silica gel with toulene - ethyl acetate 1:5+1 drop ammonia. Quantitative determination by absorbance measurement at 273 nm. The hRf value of sertraline was 70. Linearity was in the range of 25-2000 ng/zone. LOD and LOQ were 15.3 and 46.8 ng/zone. Intermediate precision was below 0.83 %. Recovery range was in the range of 99.6-100.3 %. The hRf values of acid and base-induced degradation products were 40, 52, 90 and 25.

J. Planar Chromatogr. 25, 133-137 (2012). HPTLC of thiocolchicoside (1) and aceclofenac (2) in combined dosage form on silica gel with methanol - chloroform - water 48:1:1. Quantitative determination by absorbance measurement at 254 nm. The hRf values of (1) and (2) were found to be 70 and 83, respectively. Linearity was in the range of 30-180 ng/band for (1) and 750-4500 ng/band for (2). Recovery was in the range of 98.7-101.2 % for both.

J. Planar Chromatogr. 26, 336-342 (2013). HPTLC of diosmin (1), hesperidin (2), and ascorbic acid (3) on silica gel with ethyl acetate - methanol - water 15:3:2 for (1) and (2) and ethyl acetate - methanol - water - acetic acid 15:10:2:1 for (3). Quantification by absorbance measurement at 340 nm for (1), 286 nm for (2) and 265 nm for (3). The hRf values for (1), (2) and (3) were 34, 40 and 56, respectively. Linearity was in the range of 100-800 ng/zone for (1) and (2) and 50-400 ng/zone for (3). LOD and LOQ were 6 and 17 ng/zone for (1), 4 and 13 ng/zone for (2) and 4 and 13 ng/zone for (3), respectively. Recoveries were in the range of 98.1-99.3 % for (1), 98.4-99.5 % for (2) and 98.0-99.1 % for (3). Intermediate/interday/intra-day precision was below 2 % (n=6).