J. Ethnopharmacol. 152, 292-301 (2014). HPTLC of extracts of Curcuma longa, Curcuma aromatica and Curcuma zanthorrhiza on silica gel with 1) toluene - acetic acid 4:1 (for curcuminoid determination), 2) acetonitrile - acetone - water 2:2:1 (sugars), and 3) dichloromethane (essential oils). Detection by dipping in anisaldehyde reagent (curcuminoid and essential oil systems) and aniline-diphenylamine-phosphoric acid (sugars) followed by heating at 100 °C, evaluation under white light and UV at 366 nm. Bis-demethoxycurcumin (hRF 18) was only present in Curcuma longa. The HPTLC results were compared with 1H-NMR spectroscopic analyses. The NMR analyses provided a sharper picture than HPTLC but only the combination of both methods enabled the authors of the study to understand both the general variability and the specific differences between the analyzed products.

Chinese J. Inform. Trad. Chinese Med. 20 (5), 67-69 (2013). Yinao Huoxue Keli granule is a TCM compound for the treatment of hemiplegia, numbness of limbs, deviation of mouth and tongue. For quality control, HPTLC on silica gel (1) for Salvia miltiorrhiza Bunge with chloroform – acetone – formic acid 8:1:1, detection by spraying with 3 % ferric chloride in 2 N hydrochloric acid – water 1:100 and heating at 105 °C until the spots were visible, identification by fingerprint comparison with the standard protocatechuic aldehyde and the standard ingredient drug; (2) for Panax quinquefolius L., ginsenoside Re, Rb1 and pseudoginsenoside F11 with the lower phase of chloroform – ethyl acetate – methanol – water 15:40:22:10 placed at 5-10 °C for 12 h, detection by spraying with 10 % sulfuric acid in ethanol and heating at 105 °C until the spots were visible.

J. Planar Chromatogr. 28, 139-143 (2015). TLC of 16 polyaromatic hydrocarbons on RP-18 phase. In the first direction, the plate is developed twice with n-pentane at -20 °C, and in the second direction with acetonitrile - methanol - water 12:8:3:3. Both developments were carried out over a distance of 43 mm. Detection by chemiluminescence: a solution of 225 mg Bis(2,4,6-trichlorophenyl)oxalate dissolved in 45 mL of n-butyl acetate was prepared. 125 μL hydrogen peroxide 30 % were vigorously shaken with this solution for 20 min. The mixture is suitable for chemiluminescence measurements within a period of 48 h. The best results were observed when the plate was dipped in this solution for 1 s and dried until no light reflection could be seen on the surface. Then, the TLC plate was covered by a glass plate and measured for 1 min using a very light-sensitive CCD camera. The proposed chemiluminescence screening method is able to separate PAHs from PAH oxidation products and detects benzo[a]pyrene and perylene with a LOD of 95 pg/band for benzo[a]pyrene and 48 pg/band for perylene. Although these compounds were separated from all other PAHs in the standard, a separation of both compounds was not possible from one another.

J. Liq. Chromatogr. Relat. Technol. 38, 1160-1163 (2015). HPTLC of glucose and maltose in Biomphalaria glabrata after coexposure with Echinostoma caproni and Schistosoma mansoni on silica gel with 1-butanol - glacial acetic acid - diethyl ether - deionized water 27:18:5:3. Detection by spraying with 5 g 1-naphthol and 20 mL concentrated sulfuric acid in 160 mL ethanol and 13 mL deionized water, followed by heating at 110 °C for 10 min. Quantitative determination by absorbance measurement at 515 nm. The hRF values of maltose and glucose were 40 and 50, respectively.

Food Chem. 177, 354-360 (2015). HPTLC of ochratoxin A in rice bran, wheat bran and wheat flour on silica gel with n-hexane - ethyl acetate - acetic acid 36:8:3. Quantitation by absorbance measurement at UV 366 nm. Linearity was between 50 and 300 ng/zone. The LOD and LOQ for ochratoxin A was 10 and 30 ng/zone, respectively. Recovery was in the range of 86-113 %.

J. Liq. Chromatogr. Relat. Technol. 38, 1577-1584 (2015). Reversed-phase TLC of 54 new antiproliferative 6,9-disubstituted quinobenzothiazines on RP-18 with acetone-TRIS buffer pH 7.4 mixtures containing amounts of acetone in the range of 50-85 % (v/v) in 5 % increments. Detection at UV 254 nm. The lipophilicity parameters of these compounds were determined experimentally and compared with theoretical values.

J. Planar Chromatogr. 28, 426-435 (2015). HPTLC of methyl 4-hydroxybenzoate, ethyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate and butyl 4-hydroxybenzoate on silica gel with petroleum ether - acetic acid 20:3. Quantitative determination by absorbance measurement at 254 nm. The influence of experimental settings on densitometric evaluation using the TLC Scanner 4 was investigated to assess the impact on signal intensities, peak shape/resolution and quantitative results. Peak positions can shift for up to 0.5 mm for fast scan speeds. For improved quantitative results the scan slit length should be set to 75 % of the band length, the scan speed to 5 or 10 mm/s and data resolution to 25 or 50 μm/step. The resolution mode of the optical system provided higher signal intensities compared to the light mode. Peak broadening was observed for higher scan speeds, whereby the signal height decreased significantly, if compared to the peak area evaluations. The effects of the instrumental settings on the signal intensity were less pronounced for the evaluations via peak area. Hence, peak area evaluations were more robust with regard to the changed settings.

Phytochemistry. 119, 51-61 (2015). HPTLC of cochloxanthine (1) and dihydrocochloxanthine (2) in Cochlospermum species on silica gel with acetone - hexane 1:1. Detection by spraying with anisaldehyde reagent, followed by heating at 110 °C for 5-10 min. Identification under UV light at 254 nm and 366 nm. The hRF values for (1) and (2) were 53 and 49, respectively.