J. Chinese Trad. Patent Med. (Zhongchengyao) 20 (5), 11-13 (1998). TLC on silica gel with 1) chloroform - ethyl acetate - methanol - formic acid 400:50:100:2, 2) methanol - acetone - chloroform - NH3 6:8:26:1, 3) chloroform - methanol 5:1, 4) cyclohexane - ethyl acetate 1:1. Detection 1) by spraying with 5% vanillin-sulfuric acid reagent and heating at 105°C for 5 min, 2) by spraying with 0.5% ninhydrin in ethanol and heating at 105°C for 10 min. Identification by finger print technique. Quantitation of paeoniflorin by spectrophotometry at 230 nm after elution. Recovery 97.3 ± 1.1% (n=3).

CBS 90, 6-7 (2003). HPTLC phospholipids and glycolipids from rape seed on lichrospher silica gel with chloroform - methanol - acetone - water 18:15:2:1 for phospholipid separation and with acetone - chloroform - water 30:15:2 for glycolipid separation, developing distance 70 mm each. Detection by dipping in molybdatophosphoric acid reagent (5 % in ethanol) followed by heating at 120 °C for 15 min. Quantitative determination by absorbance measurement at 720 nm.

Analysis of choline esterase inhibitors. CBS 83, 4-5 (1999) HPTLC-AMD of choline esterase inhibitors on silica gel with a 15-step gradient from methanol via dichloromethane to hexane. Detection by spraying with butyryl choline esterase solution followed by incubation at 37 °C for 30 min, and spraying with fast blue salt mixed with alpha-naphthyl acetate followed by incubation at 37 °C for 5 min. Quantitative determination by absorbance measurement at 254 nm.

J. Chinese Trad. Patent Med. (Zhongchengyao) 25 (8), 627-629 (2004). TLC on silica gel 2-fold with petroleum ether - ethyl acetate 9:1. Detection 1) under UV 254 nm. Identification by comparison with the standards. Quantitation by densitometry at 300 nm. Validation of the procedure by investigation of its precision, specificity, repeatability, reproducibility, recovery, etc.

CBS 91, 12-13 (2003). HPTLC of flavonoids with tetrahydrofuran - toluene - formic acid - water 16:8:2:1, diterpenes with toluene - ethyl acetate 9:2, and iridoids with ethyl acetate - methanol - water 77:15:8 (with chamber saturation), in horizontal developing chamber over 52 mm. Detection of flavonoids by dipping warm plate in natural products reagent (0.5 % in ethyl acetate) followed by dipping in PEG 400 solution (5 % in dichloromethane), of diterpenes by dipping in 10 % methanolic sulfuric acid followed by heating at 105 °C, and iridoids by dipping in 4-dimethylaminobenzaldehyde reagent (1 % in 1 N methanolic HCl). Visual evaluation at 366 nm (flavonoids), white light (diterpenes), and white light with sharp cut filter 560 nm (iridoids). Stability of extracts was investigated under drastic stress conditions (acid, base, light, heat, humidity).

(Laminaceae) leaves. J. Planar Chromatogr. 17, 18-21 (2004). TLC of polyphenols and rosmarinic acid on silica gel with 1) toluene - methyl acetate - formic acid 5:4:1; 2) ethyl acetate - methanol - water 77:13:10; 3) ethyl acetate - diethyl ether 8:2. Detection a) at 254 nm, b) in fluorescence after spraying with Neu-PEG reagent, and c) in visible light after spraying with 10 % iron(III) chloride solution. Quantitative determination by densitometry at 254 nm and spectra recording from 200 to 500 nm for identification.

Indian Drugs 41 (3), 149-152 (2004). HPTLC on silica gel with toluene - ethyl acetate 1:24. Quantitative determination by absorbance measurement at 260 nm. The linearity range is 100-500 µg/µL and recovery is 100.7 %. The method was validated and compared with HPLC. The results were comparable. Advantages of HPTLC in terms of handling many samples. Thus, a simple, fast and precise HPTLC method was developed for quantification of ebastine in tablets.

J. Planar Chromatogr. 17, 154-156 (2004). HPTLC of pioglitazone hydrochloride ((±)-5-{p-[2-(5-ethyl-2-pyridyl)-ethoxy]benzyl}-2,4-thiazolidinedione hydrochloride) and glimepiride (trans-3-ethyl-2,5-dihydroxy-4-methyl-N-[2-[4-[[[[(4-methylcyclohexyl)amino]-carbonyl]amino]sulfonyl]phenyl]ethyl]-2-oxo-1H-pyrrole-1-carboxamide)and atorvastatin as internal standard on silica gel after pre-washing in a twin-trough chamber after pre-saturation with toluene - methanol - ethyl acetate - formic acid 70:20:15:0.1. Evaluation by densitometry at 235 nm.