J. AOAC Int. 91, 339-343 (2008). HPTLC of conessine on silica gel (prewashed with methanol) with toluene - ethyl acetate - dimethylamine 13:5:2 in a saturated twin-trough chamber. Detection by spraying with Dragendorff reagent, followed by spraying with a 10 % solution of aqueous sodium nitrite. Quantitative determination by densitometry at 520 nm. Linearity was between 10 and 60 ng/spot. The limit of detection was 3 ng/spot.

J. Pharm. Biomed. Anal. 43 (2), 722-726 (2007). HPTLC of imatinib mesylate both as a bulk drug and in formulations on silica gel aluminium plates with chloroform - methanol 3:2. Quantitative determination by absorbance measurement at 276 nm. Linearity was between 100 and 1000 ng per spot. The limit of detection and quantitation was 10 and 30 ng, respectively. The method is repeatable, selective and accurate and can be used for stability control.

J. Liq. Chromatogr. Relat. Technol. 31, 1871-1880 (2008). HPTLC for the determination of neutral lipid profils using a standard mixture (containing cholesterol, oleic acid, triolein, methyl oleate, cholesteryl oleate) on silica gel (plates with 19 scored lanes and a preadsorbent application area, prewashed by development with dichloromethane - methanol 1:1) with petroleum ether - diethyl ether - acetic acid 80:20:1 in a saturated twin-trough chamber. Detection by spraying with 5 % ethanolic phosphomolybdic acid and heating for 10 min at 115 °C. Quantitative determination by absorbance measurement at 610 nm.

J. Liq. Chromatogr. Relat. Technol. 30, 2209-2219 (2007). HPTLC of artemisinin in Artemisia annua on silica gel with cyclohexane - ethyl acetate - acetic acid 20:10:1 in a twin-trough chamber saturated for 20 min. Detection by immersion in modified anisaldehyde reagent (20 mL acetic acid, 4 mL sulfuric acid, 2 mL of anisaldehyde in a mixture of 100 mL ethanol and 80 mL water) for 1 s. After 1 min the plate was heated at 100 °C for 12 min. Quantitative determination by fluorescence measurement at 520 nm with cut-off filter at 540 nm.

J. Chromatogr. A 1209 (1-2), 230-237 (2008). TLC of purines (adenosine and its major metabolites, inosine, and hypoxanthine) in rat brain tissue preparations, on silica gel with a two-step gradient mobile phase consisting of (1) n-butanol – water – acetonitrile - 10% ammonia - acetic acid 10:4:8:2:1 and (2) n-butanol – chloroform – acetonitrile - 10 % ammonia - acetic acid 10:4:8:2:1. Quantitative determination by absorbance measurement at 258 nm (via peak area). Application of the method to estimate the endogenous purines in discrete regions of rat brain. Development of a novel protocol for tissue preparation using 0.1 M HCl and 0.15 M NaOH solutions in 60 % methanol, which provided well-resolved peaks and high recoveries.

heracleifolia, C. dahurica, or C. americana. J. AOAC Int. 91, 1257-1264 (2008). HPTLC of black cohosh extracts and references cimifugin, 23-epi-26-deoxyactein, actein on silica gel with toluene - ethyl formate - formic acid 5:3:2 in a twin-trough chamber saturated for 20 min. HPTLC plates were conditioned to 5 % relative humidity or less. For identification of species derivatization by dipping for 1 s in sulfuric acid reagent (10 % in methanol) followed by heating at 100 °C for 5 min and evaluation under white light and UV 366 nm. For detection of adulteration with Cimicifuga foetida derivatization with boric acid/oxalic acid reagent, for detection of adulteration with C. heracleifolia and C. dahurica derivatization with antimony(III) chloride reagent. Evaluation under UV 254 nm and after derivatization under UV 366 nm and white light. The method allows visual detection of 5 % of these adulterants in Cimicifuga racemosa.

Ind. J. Pharma Educ. Res. 42(1), 59-64 (2008). Curanams are an important group of formulations in ayurvedic and siddha medicine. HPTLC of sennoside A and piperine in methanolic and ethyl acetate extracts of Nilavakai Curanam on silica gel with n-hexane - ethyl acetate - formic acid - acetic acid 15:5:1:1. Quantitative determination by absorbance measurement at 254 nm. The methanolic extract of the laboratory formulation contained 0.61 % and 1.4 % piperine and sennoside A respectively, whereas the ethyl acetate extract contained 1.0 % and 4.2 %. The methanolic extract of the commercial formulation contained 0.27 % and 0.42 % and the ethyl acetate extract contained 0.27 and 0.53 % respectively. The method was linear in the range of 15-105 ng/spot and 5-30 ng/spot for piperine and sennoside A respectively. The recovery was 98.5 % for both compounds.

J. AOAC Int. 91, 750-755 (2008). HPTLC of acetylsalicylic acid and clopidogrel bisulfate ((alphaS)-alpha-(chlorophenyl)-6,7-dihydrothieno[3,2-c]pyridine-5-(4H)-acetic acid methyl ester) on silica gel using ethyl acetate - methanol - toluene - acetic acid 50:10:40:1. Quantitative determination by absorbance measurement at 235 nm.