J. Planar Chromatogr. 25, 65-71 (2012). HPTLC of dapsone in presence of its oxidative degradants on silica gel with acetate - toluene 1:1. Quantitative determination by absorbance measurement at 289 nm. Linearity was in the range of 0.5-6.0 µg/zone. Recovery was 99.4 %. The method showed comparable results to a validated HPLC method.

J. Planar Chromatogr. 26, 190-195 (2013). Enlarging of the two-phase microcircular planar liquid chromatography (PLC) into a three-phase chromatographic technique by adding gas flow containing specific chemicals like acids, bases, alcohols, esters, hydrocarbons. The flow speed of 2 L/min flushes the gas volume over the 100 mm × 100 mm PLC plate 200 times per minute at room temperature. Reproducibility was obtained in the ±0.1 % range in qualitative evaluations and ±0.5 % down to ±0.05 % range for quantitative analyses.

J. Planar Chromatogr. 25, 101-107 (2012). HPTLC of mixtures of the pesticides glyphosate, acephate, chlorpyrifos, malathion/methyl parathion, and isoproturon on silica gel impregnated with 0.01 % CTAB (Ncetyl-N,N,N-trimethyl ammonium bromide) and developed with hexane - acetone 1:1. LOD of the pesticides was aproximately 20 µg/band. The method can also be applied for fast determination of pesticides in cereals, vegetables and fruit grains.

Chinese J. of Inform. on TCM 19 (9), 59-60 (2012). Some Aconitum medicinal herbs, such as Aconite root, Radix Aconiti Kusnezoffii, Radix Aconiti Lateralis Preparata etc. are used as the component drugs in TCM anti rheumatic preparations like Hulisan capsules, Yaoxitong capsules and Panlongqi tablets. The main active component in Aconitum is aconitine which has significant anti-inflammatory and analgesic activity, but is a potent toxic ingredient as well. For quality control of the formulations and ensuring their medication safety, a method for the limit test of aconitine in Hulisan capsules, Yaoxitong capsules and Panlongqi tablets has been presented. TLC on silica gel with cyclohexane – ethyl acetate – diethylamine 10:7:1, detection first by spraying with 5 % potassium iodobismuthate in water – hydrochloric acid 200:1 and then by exposing to iodine vapors, viewing in daylight. Semiquantification of aconitine by comparison of zones with the standard applied in concentrations meeting the safety limit.

J. Liq. Chromatogr. Relat. Technol. 36, 2395-2404 (2013). HPTLC of carbidopa (1) and levodopa (2) in tablets on RP-18 with citrate buffer (pH 3.0) - methanol - formic acid 96:4:5. Detection by spraying with 0.02 % 2,2-diphenyl-1-picrylhydrazyl solution in ethanol (DPPH radical reagent). The hRf values of compounds (1) and (2) were 39 and 63, respectively. Linearity was in the range of 50-300 ng/zone for both (1) and (2). Intermediate precision was below 3.7 %. LOD and LOQ were 20.5-60.7 ng/zone for (1) and 27.8-61.1 ng/zone for (2), respectively. Recovery (by standard addition) was 99.6-95.4 % for both.

J. Planar Chromatogr. 26, 510-516 (2013). HPTLC of metoprolol tartrate (1) and hydrochlorothiazide (2) and hydrochlorothiazide degradation product (3) on silica gel with acetate - toluene - methanol - ammonium hydroxide 33 % 10:6:3:1. Quantification by absorbance measurement at 275 nm. The hRf values for compounds (1) to (3) were 8, 20 and 38, respectively. Linearity was in the range of 5-40 µg/zone for (1) and 3-10 µg/zone for (2). LOD and LOQ were 730 and 2180 ng/zone for (1) and 80 and 250 ng/zone for (2). Recovery was in the range of 98.4-101.9 % for both (1) and (2). Intermediate/interday/intra-day precision was below 1 %. The method showed comparable results with a validated HPLC method.

Food Res. Int. 54, 1229-1236 (2013). HPTLC of p-coumaric acid in the leaves of Enhalus acoroides (L.f.) Royle, Thalassia hemprichii (Ehrenberg) Ascherson, Halodule pinifolia (Miki) den Hartog, Syringodium isoetifolium (Ascherson) Dandy, Cymodocea serrulata (R. Brown) Ascherson & Magnus and Cymodocea rotundata Ehrenberg & Hemprich ex Ascherson on silica gel with toluene - ethyl acetate - methanol - glacial acetic acid 16:2:1:1. Quantitative determination by absorbance measurement at 254 nm. The hRf value of p-coumaric acid was 42. Linearity was in the range of 100-500 ng/zone. LOD and LOQ were 15 and 45 ng/zone.

J. Chil. Chem. Soc. 58, 1663-1666 (2013). HPTLC of rosiglitazone (1) and glimepiride (2) in tablet dosage form on silica gel with methanol - toluene - ethyl acetate 1:8:1. Quantitative determination by absorbance measurement at 228 nm. The hRf values for (1) and (2) were 39 and 20, respectively. Linearity was in the range of 100-1500 ng/zone for (1) and 100-1500 ng/zone for (2). LOD and LOQ were 30 and 35 ng/zone for (1) and 85 and 90 ng/zone for (2), respectively. Recovery was 96 % for (1) and (2). Intermediate intra- and inter-day precision was below 2 % (n=6).