J. Liq. Chromatogr. Relat. Technol. 32, 1289-1298 (2009). HPTLC of phosphatidylcholine (1), phosphatidylethanolamine (2), sphingomyelin (3), sulfatides (4), and cerebrosides (5) in tissue samples of the lizard Uta stansburiana on silica gel with chloroform - methanol - water 65:25:4. Detection by spraying with 10 % cupric sulfate in 8 % phosphoric acid, followed by heating at 140 ºC for 30 min. Quantitative determination by absorbance measurement at 370 nm. The hRf values of (1)-(5) were 40, 56, 39, 51 and 71, respectively.

J. Planar Chromatogr. 24, 524-528 (2011). TLC of cefixime on silica gel with toluene - ethyl acetate - formic acid - water 5:29:11:5 with chamber saturation for 30 min at 25 +/- 2 °C. The hRf value was 54. Quantitative determination by densitometry in absorbance mode at 293 nm. Linearity was between 500 and 1500 ng. The repeatability (%RSD) was below 2 %. The limit of detection and the limit of quantification was 9 and 42 ng/zone, respectively. The recovery was between 98.9-100.3 %.

J. Planar Chromatogr. 24, 99-104 (2011). TLC of candesartan and losartan on silica gel with 1,4-dioxane - hexane - 99 % formic acid 50:50:1. Quantitative determination by densitometry at 258 nm for candesartan and at 243 nm for losartan, videoscanning at 254 nm for both drugs. The hRf value for candesartan was 47 and for losartan 35. Linearity was between 0.2 and 1.4 µg/band for both drugs with correlation coefficients of 0.9997 and 0.9981 for candesartan, and 0.9986 and 0.9982 for losartan, for densitometry and videoscanning, respectively. Robustness (%RSD, peak area) was less than 1.9 and 0.8 % for candesartan, and 2.2 and 0.9 % for losartan in densitometry and videoscanning, respectively. The repeatability and intermediate precision (%RSD, two lowest amounts) were less than 3.6 and 4.7 % for candesartan and less than 4.7 and 5.3 % for losartan. Mean recoveries for candesartan were 103.8-104.9 % for densitometry and 99.2-100.7 % for videoscanning; for losartan the respective values were 100.8-105.4 % and 98.6-99.2 %.

J. Liq. Chromatogr. Relat. Technol. 34, 2548-2464 (2011). HPTLC of tocopherol acetate (1) and tocopherol (2) in oral fluid vitamin E on silica gel with chloroform - cyclohexane 11:9. Quantitative determination by absorbance measurement at 202 nm for (1) and 272 nm for (2). The hRf values of (1) and (2) were 47 and 38, respectively. Linearity was in the range of 2-8 µg/band for (1) and (2). Limits of detection and quantification were found to be 50 and 150 ng/zone for (1). Precision was below 2 %. The intermediate/inter-day/intra-day precision was 0.4 % (n = 6). Recovery (by standard addition) was in the range between 99.8-101.5 %. Tocopherol acetate was better separated from tocopherol using normal phase TLC than by reversed phase TLC.

J. of Chromatogr. B 879 (30), 3565-4573 (2011). Presentation of a novel “target constituent knock-out” strategy applied for preliminary screening of antibacterial constituents in Calculus bovis. The strategy contained the following steps: 1) the single constituents (A-F) in C. bovis samples were knocked out by TLC on silica gel with toluene - acetic acid - water 30:25:2, detection under UV 366 nm; 2) the knocked-out constituents were identified by UPLC–ELSD; 3) the antibacterial activities of the knocked-out constituents and C. bovis samples on Staphylococcus aureus were evaluated by microcalorimetry combined with principal component analysis; 4) the activities of the knocked-out constituents and the total extract of C. bovis, also the interaction properties between these single constituents and the total extract were elucidated. The strategy proved to be useful for screening active constituents and elucidating the multi-component interactions in C. bovis, and helpful in understanding the pharmacodynamic actions and the quality control of traditional Chinese medicines.

Der Pharmacia Letter 2(4), 440-446 (2010). TLC of glibenclamide on silica gel with toluene - ethyl acetate - methanol 16:1:2. The hRf value was 45. Quantitative determination by densitometry in absorbance mode at 229 nm. The method was linear in the range of 40-200 ng/band. The recovery was 99.8 %.

J. Liq. Chromatogr. Relat. Technol. 34, 1502-1517 (2011). HPTLC of irinotecan in bulk drug and injectable formulations on silica gel with acetone - ethyl acetate 17:3 + 1 drop acetic acid. Quantitative determination by absorbance measurement at 366 nm. The hRf of irinotecan was 31. Linearity was 50-500 ng/zone. The LOD and LOQ was found to be 10 and 33 ng/zone. The intra-day precision was 4.3 % (n = 6) and inter-day precision over three different days was 3.1 %. Intra-day and inter-day accuracy were 96.9-100.3 % and 96.5-98.7 %, respectively. Recovery (by standard addition) ranged from 94.6-101.4 %.

J. Planar Chromatogr. 24, 44-47 (2011). HPTLC of nitrazepam on silica gel with benzene - ethanol 5:1 in a horizontal chamber with saturation for 50 min. Quantitative determination by densitometry in absorbance mode at 196 nm. The hRf of nitrazepam was 68. Linearity was in the range of 0.25-10.0 µg/zone. Mean recovery was 98.8 % and 98.8 % for tablet and pure powder, respectively. Precision and accuracy (%RSD) were 1.3 % and 1.2 %, respectively. LOD and LOQ were 0.49 and 1.52 µg/mL, respectively.