J. AOAC Int. 79, 656-659 (1996). TLC of antifungal agents (alone or combined with other drugs) in various pharmacopoeial or proprietary creams and ointments after extraction on silica with n-hexane - chloroform - methanol - diethylamine 50:40:10:1 as mobile phase. Visualization under UV 254 nm; quantification by densitometry at 220 nm. Recoveries 100.2 %.

J. Planar Chromatogr. 9, 388-390 (1996). HPTLC of verapamil hydrochloride (5-[N-(3,4-dimethoxyphenethyl)-methylamino]-2-(3,4-dimethoxyphenyl)-2-isopropylvaleronitrile monohydrochloride) on silica with ethyl acetate - methanol - water 100:13:10. Quantification by densitometry (absorbance) at 278 nm. Intraday and interday precision were 0.17-0.62% and 0.88-1.00%, respectively.

Indian Drugs 35 (2), 79-85 (1998). HPTLC on silica gel with chloroform - methanol - acetic acid 90:15:1. Densitometry at 238 nm. The HPTLC method was specific.

CBS 85, 4-5 (2000). HPTLC of peptide fragment A on lichrospher silica gel with dichloromethane over 50 mm. Quantitative determination by absorbance measurement at 250 nm. Precision is 0.23 % (n=10 at 50 ng) and repeatability 2.9 % (n=30 over 5 plates at 50 ng), recovery is found to be 104 % at 50 ng.

J. Chinese Trad. Patent Med. (Zhongchengyao) 25 (9), 711-715 (2004). TLC on silica gel with 1) ethyl acetate - butanone - formic acid - water 5:3:1:1, 2) chloroform - methanol - formic acid 200:25:50:1, 3) petroleum ether - diethyl ether 2:1, 4) chloroform - methanol - acetone - glacial acetic acid 30:1:2:3, 5) ethyl acetate - formic acid - glacial acetic acid - water 15:1:1:2. Detection 1) by spraying with 1 % FeCI3 in ethanol, 2) spraying with 5 % vanillin - H2SO4 solution and heating, 3) under UV 365 nm, 4) by spraying with 10 % H2SO4 in ethanol and heating at 105 ºC. Identification by fingerprint techniques. Quantification of baicalin by HPLC.

J. Chinese Trad. Patent Med. (Zhongchengyao) 25 (8), 619-622 (2004). TLC on silica gel with 1) petroleum ether - ethyl acetate 17:3; 2) chloroform - methanol - water 32:8:1; 3) chloroform - methanol 100:1; 4) chloroform - methanol - water 13:7:2. Detection 1) under UV 254 nm; 2) by spraying with 5 % H2SO4 in ethanol and heating at 105 ºC and under UV light; 3) by spraying with 10% H2SO4 in ethanol and heating at 110 ºC . Identification by finger print technique. Quantitation of ginsenoside rg by densitometry at 510 nm.

CBS 91, 14-15 (2003). HPTLC of hawthorn extract on silica gel with ethyl acetate - methanol - water - formic acid 50:2:3:6, of passion flower extract on silica gel with tetrahydrofuran - toluene - formic acid - water 16:8:2:1, and of chrysine on RP-18 W phase with tetrahydrofuran - methanol - water - formic acid 4:6:14:1. Detection by dipping the warm plate in natural products reagent (0.5 % in ethyl acetate) followed by dipping in PEG 400 solution (5 % in dichloromethane). Visual evaluation at 366 nm.

J. AOAC Int. 86, 909-915 (2003). In quality control and stability testing of herbal medicinal products, fingerprint chomatograms are used as powerful tools to evaluate and compare the composition of compounds in such products. To fulfill the ICH- and GMP-based regulatory requirements in pharmaceutical QC, chromatographic fingerprint analysis needs to be validated. By considering the stationary phase, sample application, developing solvents, chromatogram development, plate labeling, derivatization, documentation, and chromatographic equipment the paper provides a comprehensive concept for evaluating validation parameters for planar chromatographic fingerprinting based on a standardized methodology. Validation parameters addressed include stability of the analyte, selectivity, robustness testing, and method reproducibility.