CBS 97, 9-11 (2006). HPTLC of trigonelline in fenugreek (Trigonella foenum-graecum) on silica gel in a saturated twin-trough chamber with n-propanol - methanol - water 4:1:4 over 80 mm. Quantitative determination by absorbance measurement at 269 nm. The hRf value of trigonelline was 46 and selectivity regarding matrix was given. Linearity was between 100 and 1200 ng/zone. The inter- and intraday precision was below 1 %. The limit of detection and quantification was 2.3 and 7.6 ng/zone, respectively. Recovery (by standard addition) was 99 - 101 %.

Indian Drugs 44(8), 640 (2007). TLC, HPTLC and UV spectrophotometric methods have been developed and evaluated to compare the colour properties of saffron and Nyctanthes arbor-tristis which shows an orange red colour. HPTLC and TLC of methanolic extracts of saffron and calyx of Nyctanthes arbor-tristis on silica gel with ethyl acetate - isopropanol - water 13:5:2. Both extracts showed a major zone with hRf 23 corresponding to crocin, the major colour constituent of saffron. The presence of crocin was confirmed by UV spectra. TLC, HPTLC and UV data confirm the coloring similarity of Nyctanthes arbor-tristis.

J. Sep. Sci. 30, 3174-3180 (2007). HPTLC of vanillin and nine related phenolic compunds in Vanilla planifolia pods on RP-18 with methanol – water – isopropanol – acetic acid 30:65:2:3. Quantitative determination by absorbance measurement at 280 nm. The hRf value of vanillin was 41. Linearity was between 0.990 and 0.999 ng/zone. Repeatability was better than 3.5 %. The limits of detection and quantification were between 5 and 70 ng/zone and between 10 and 4000 ng/zone, respectively. Recovery was between 95.4 and 102.5 %.

Pharmazie 62, 900-901 (2007). TLC of dihydroartemisinin and the degradation products 2-(3-oxobutyl)-3-methyl-6-(2-propanol)-cyclohexanon and 2-(3-oxobutyl)-3-methyl-6-ethyl-cyclohexanon on silica gel with chloroform - methanol 19:1. Detection by spraying with vanillin reagent (0.5 g vanillin in 80 mL sulfuric acid and 20 mL ethanol).

J. Planar Chromatogr. 21, 103-106 (2008). HPTLC of (-)-epicatechin, (+)-catechin, (-)-epigallocatechin, (-)-gallocatechin, (-)-catechin gallate, and (-)-epicatechin gallate on RP-18 at room temperature and 75 % relative humidity in an automated development chamber with methanol - water - formic acid 30:70:6. Detection by spraying with diazotized sulfanilic acid. Quantitation by densitometry at 440 nm.

J. AOAC Int. 91, 1154-1161 (2008). HPTLC of 3 key whithanolides, namely withaferin-A, 12-deoxywithastramonolide, and withanolide-A on silica gel with dichloromethane - methanol - acetone - diethylether 15:1:1:1 in a saturated twin-trough chamber at 25 °C and relative humidity of 35-40 %. Quantitative determination by absorbance measurement at 230 nm. Detection by immersion in freshly prepared vanillin-sulfuric acid reagent for 2 s followed by heating at 110 °C for 10 min.

leaf by high-performance thin-layer chromatography. J. Planar Chromatogr. 22, 225-228 (2009). HPTLC of negundoside on silica gel (prewashed with methanol) with ethyl acetate - methanol - water - glacial acetic acid 78:12:7:3 in a twin trough chamber saturated for 20 min. Quantitative determination by absorbance measurement at 267 nm.

Indian Drugs 46(2), 109-112 (2009). HPTLC of chloroform extracts of stem bark of Terminalia alata and Terminalia arjuna on silica gel with chloroform - methanol 9:1. Arjunolic acid and maslinic acid were used as marker compounds. Detection by treatment with vanillin-sulphuric acid reagent. Quantitative determination by absorbance measurement at 254 nm. The fingerprint profile along with other physico-chemical data helped in the correct authentification and standardization of both plant species.