J. Planar Chromatogr. 25, 320-325 (2012). HPTLC of ursolic acid in the leaves of Diospyros melanoxylon on silica gel with chloroform - methanol 19:1. Detection by dipping in 5 % methanolic sulphuric acid reagent and heating at 105 °C for 3 min. Quantitative determination by absorbance measurement at 540 nm. Linearity was in the range of 50-450 ng/zone for ursolic acid. Limits of detection and quantification were found to be 20 and 40 ng/zone. Recovery (by standard addition) was 97.5 %.

J. Liq. Chromatogr. Relat. Technol. 35, 1429-1443 (2012). HPTLC of azorubin (1) and sunset yellow (2) in powders for jelly desserts on silica gel with n-butyl alcohol - acetic acid - ethanol - water 10:2:1:5. Quantitative determination by absorbance measurement at 485 nm for (2) and 515 nm for (1). The hRf values of (1) and (2) were 45 and 53, and selectivity regarding matrix was given. Linearity was between 100-400 ng/zone for (1) and 200-450 ng/zone for (2). The %RSD values for repeatability studies were below 2. The limits of detection and quantification were 9 and 19 ng/zone, for (1) and 11 and 23 ng/zone for (2), respectively. Recovery was higher than 96.9 % for (1) and 95.7 % for (2).

J. Planar Chromatogr. 25, 445-449 (2012). HPTLC of bergenin in the stem-bark and roots of Mallotus phillippensis on silica gel with ethyl acetate - methanol - acetic acid - formic acid 16:2:1:1. Quantitative determination by absorbance measurement at 284 nm and by TLC-MS using the TLC-MS Interface. The hRf of bergenin was 49. Linearity was in the range of 100-600 ng/zone. Limits of detection and quantification were 29, 37 and 98 ng/zone, respectively. Intermediate intra-day/inter-day precision was 1.1 % (n=6). Recovery was between 96.6 and 98.9 %.

J. Planar Chromatogr. 25, 559-565 (2012). HPTLC of zafirlukast on silica gel with toluene - methanol - acetone 7:2:1. Quantitative determination by absorbance measurement at 240 nm. Linearity was in the range of 50-400 ng/zone. Limits of detection and quantification were 16 and 50 ng/zone, respectively.

J. Liq. Chromatogr. Relat. Technol. 35, 2396-2407 (2012). HPTLC of vanillin in the roots of Decalepis hamiltonii Wight and Arn on silica gel with toluene - ethyl acetate 9:1. Quantitative determination by absorbance measurement at 254 nm. The hRf value of vanillin was 42. Linearity was in the range of 2-12 µg/zone. Limits of detection and quantification were 1.3 and 3.9 µg/zone. The intermediate/inter-day/intra-day precision was 1.3 % (n=3), respectively. Recovery was between 99.4 and 100.3 %.

J. Planar Chromatogr. 25, 200-207 (2012). New horizontal developing chamber with advantages for stepwise gradient elution in RP HPTLC. It is shown that a previously developed computer program can be successfully applied to predictive calculations of solute retention in stepwise gradient elution.

J. Sep. Sci. 36, 1104-1111 (2013). Micro TLC of equilin (1), estetrol (2), estriol (3), 17alpha-estradiol (4), 17beta-estradiol (5), estrone (6), 17alpha-hydroxyprogesterone (7), 20alpha-hydroxyprogesterone (8) and progesterone (9) on RP-18 with 30 to 100 % methanol. Detection by dipping into PMA reagent (10 % phosphomolybdic acid in methanol) and heating at 100 °C for 10 min. The breakthrough volume was calculated to optimize the extraction process of nine steroids using solid-phase extraction retention data.

J. Planar Chromatogr. 26, 5-13 (2013). HPTLC of polystyrenes with molecular weight from 1920 to 520000 Da on silica gel with cyclohexane - tetrahydrofuran 39:11. The method allowed different ranges of molecular weight to be separated as a function of mobile phase composition using slight variations of cyclohexane and tetrahydrofuran. Comparison with other techniques for molecular weight distribution analysis is also discussed.