J. Liq. Chromatogr. Relat. Technol. 35, 1415-1428 (2012). HPTLC of prometryn in wine samples on silica gel with tetrahydrofuran - n-heptane 1:4 in the first direction and with methanol - water 7:3 in the second direction after the plate was turned by 90°. Quantitative determination by absorbance measurement at 223 nm. The hRf value of prometryn was 35. Linearity was in the range of 220-1320 ng/zone. Limits of detection and quantification were 110 and 330 ng/zone. The method was compared with a validated HPLC-DAD method and both methods are useful for correct identification of pesticides in complicated mixtures.

J. Planar Chromatogr. 25, 251-258 (2012). TLC of trans-resveratrol (1), pterostilbene (2), and p-coumaric acid (3) in samples of recombinant bacterial cultures, food supplements, and wine on silica gel with n-hexane - ethyl acetate - formic acid 20:19:1. Quantitative determination by absorbance measurement at 286 nm (3) and 303 nm for (1) and (2).

J. Liq. Chromatogr. Relat. Technol. 35, 28-39 (2012). HPTLC of metformin hydrochloride and glipizide in tablet formulation on silica gel with water - methanol 3:1 + 1 drop ammonia. Quantitative determination by absorbance measurement at 236 nm. The hRf value of compounds (1) and (2) were 22 and 85 and selectivity regarding matrix was given. Linearity was in the range of 5000-25000 ng/band for (1) and 50-250 ng/band for (2). Limits of detection and quantification were 991 and 3003 ng/band for (1) and 10 and 29 ng/band for (2), respectively. Recovery (by standard addition) was between 98.1 and 101.5 % for both (1) and (2).

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).

Phytochem. Anal. 24, 303-308 (2013). HPTLC of chicoric 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. Qualitative identification under UV 366 nm. Images were quantified and transformed into chromatograms, as signal intensities (peaks) versus hRf (retention factor) for a artificial neural network (ANN) correlation. LOD were 19, 46 and 29 ng/band, whereas LOQ were 63, 154 and 98 ng/band for (1), (2) and (3), respectively.

J. Planar Chromatogr. 26, 119-124 (2013). HPTLC of methyl- (1), ethyl- (2), propyl- (3), and butylparaben (4) in cosmetics on cyanopropyl plates with water - acetonitrile - dioxane - ethanol 8:2:1:1+1 drop ammonia. Quantitative determination by absorbance measurement at 255 nm and by bioutographic analysis using Vibrio fischeri bacteria. LOD for (3) and (4) was 100 ng/zone, for (1) 80 ng/zone, and 69 ng/zone for (2). The LOQ for (3) and (4) was 120 ng/zone, for (1) 90 ng/zone, and 78 ng/zone for (2).

J. Planar Chromatogr. 25, 117-121 (2012). HPTLC of octachlorodipropyl ether on silica gel with toluene - acetic acid - water 20:20:1. Detection by spraying with 2 N alcoholic potassium hydroxide, followed by heating at 120 °C for 30 min, overspraying with 1 % silver nitrate in 30 % nitric acid and then exposed to unfiltered UV illumination for approximately 15 min. Quantitative determination by absorbance measurement at 399 nm. The hRf values of octachlorodipropyl ether and photodegradation products O1 and O2 were 93, 19 and 82, respectively.

J. Liq. Chromatogr. Relat. Technol. 36, 1323-1329 (2013). HPTLC of amlodipine (1) and perindopril (2) in bulk powder and tablets on silica gel with n-butanol - water - glacial acetic acid 4:5:1. Quantitative determination by absorbance measurement at 365 nm and 215 nm, for (1) and (2), respectively. The hRf values for (1) and (2) were 72 and 48, respectively. Linearity was 1-6 µg/mL for (1) and 2-10 µg/mL for (2). LOD and LOQ were 0.28 and 0.86 µg/mL for (1) and 0.24 and 0.75 µg/mL for (2), respectively. The interday and intra-day precisions were below 1.3 % (n=3). Recovery (by standard addition) was 98.0-99.6 % for both (1) and (2). Comparable results were obtained when compared with validated HPLC and first-derivative spectrophotometry methods, resulting in short scan time, large sample capacity, and use of minimal volume of solvent.