Indian Drugs 45(8), 663-666 (2008). HPTLC of geranial and luteolin from leaves of Cymbopogon citratus on silica gel with toluene - ethyl acetate 9:1 for geranial and toluene - ethyl acetate - formic acid 10:7:1 for luteolin. Densitometric evaluation at 200 nm (geranial) and 254 nm (luteolin). Alcoholic extracts of the plant leaves were found to contain 1.34 % and 1.49 % of geranial and luteolin respectively.

J. AOAC Int. 91, 1237-1243 (2008). HPTLC of zinc bis(O,O’-diisobutyl dithiophosphate), zinc bis(O,O’-didodecyl dithiophosphate), and Aglamol 99 on RP-2 by automated multiple development with methanol - water - acetic acid 6:3:2 for 25 mm, then acetonitrile - water 11:9 for 60 mm, and again acetonitrile - water for 80 mm, or on silica gel with a 14-step gradient based on toluene. For derivatization, the plate was dipped in a solution of 0.05 % primuline in acetone - water 4:1 for 1 s and immediately dried in warm air. Quantitative determination by fluorescence measurement at 366/>400 nm and by absorbance measurement at 220 nm. HPTLC-ATR-IR and HPTLC-FTIR, as well as HPTLC/DART-MS and HPTLC/ESI-MS were applied for identification.

J. Chromatogr. A 1216(20), 4485-4491 (2009). TLC of (+)-catechin and (-)-epicatechin on cellulose with water. Detection with 4-dimethylaminocinnamaldehyde in HCl produced blue bands. Detection with vanillin reagent produced quickly fading red spots. Quantitative determination by absorbance measurement at 655 nm. Linearity was between 2 to 12 ng/zone and a polynomial regression fit from 2 to 30 ng/zone. The repeatability of the separation of 20 ng/zone was 3.5 % (%RSD, n = 6). The visible limit of detection of both standards was 1 ng/zone, the densitometric limit of detection was 0.2 ng/zone. The optimized 4-dimethylaminocinnamaldehyde reagent is superior to the more frequently used vanillin reagent and is applicable also for determination of mixtures containing other catechins, such as (-)-catechin, (-)-epicatechin gallate, (-)-epigallocatechin gallate, procyanidin A2, procyanidin B1 and procyanidin B2.

J. Planar Chromatogr. 22, 15-17 (2009). HPTLC of biogenic amines (spermidine, putrescine, cadaverine, histamine, and tyramine) on silica gel (with concentration zone) in a twin trough chamber saturated for at least 1 h with acetone - ammonia 19:1. Detection by heating at 75 °C for 2 min, followed by spraying with ninhydrin reagent (300 mg ninhydrin in 100 mL n-butanol - glacial acetic acid 97:3) and again heating at 75 °C for 2 min. Quantitative determination by absorbance measurement at 410 nm.

Abstract No. 9147, IHCB (2009). HPTLC of quercetin in methanolic leaf extracts of Viola odorata on silica gel with ethyl acetate - formic acid - glacial acetic acid - water 100:11:11:26. Quantitative determination by absorbance measurement at 366/>400 nm for quantification. The extract contained 0.36 % quercetin.

Phytochem. Anal. 19, 244-250 (2008). HPTLC of taraxerol on silica gel in a saturated twin trough chamber with hexane - ethyl acetate 4:1. Detection by spraying with anisaldehyde reagent. Quantitative determination by absorbance measurement at 420 nm. Limits of detection and quantification were 31 and 105 ng/spot, respectively.

Separation and analysis of duloxetine hydrochloride and olanzapine in a synthetic mixture. J. Planar Chromatogr. 22, 121-126 (2009). HPTLC of duloxetine hydrochloride (and degradation products after acidic and basic hydrolysis, oxidation and photodegradation) on silica gel with toluene - methanol - 10 % ammonia 60:26:1 in a twin trough chamber saturated at 25 °C. Quantitative determination by absorbance measurement at 231 nm. The hRf value was 39. Linearity was between 60-480 ng/band. The limit of detection and quantification was 20 and 60 ng/spot, respectively. For separation of duloxetine hydrochloride and olanzapine in a synthetic mixture HPTLC with acetone - methanol - triethylamine 10:6:1. Quantitative determination by absorbance measurement at 240 nm. The hRf values were 63 and 77, respectively. Linearity was between 100-800 ng/band.

J. Planar Chromatogr. 22, 109-113 (2009). HPTLC of purpurin on silica gel with toluene - ethyl acetate - formic acid 98:2:1 in a twin trough chamber saturated for 20 min at 25 +/- 2 °C. Quantitative determination by absorbance measurement at 255 nm. The limit of detection and quantification was 50 and 100 ng/band, respectively.