Part XV. J. Planar Chromatogr. 11, 61-63 (1998). Separation of 16 isomeric methylanilines and chloroanilines by TLC on silica gel and on silica gel impregnated with manganese salts and correlation of the pKa values of the compounds with RM values and with the numerical values of topological indexes. Most accurate prediction of the pKa values of the aniline derivatives investigated was achieved by use of biparametric equations employing RM values and the topological indexes °B or 'B. - TLC of aniline derivatives on 1. silica gel with benzene - ethyl acetate - acetic acid 6:3:1; 2. on silica gel impregnated with a 10% aqueous solution of Mn(C2H3O2)?4 H2O with the a.m. eluent. Detection by spraying with 4-dimethylaminobenzaldehyde solution.

J. Chinese Trad. Patent Med. (Zhongchengyao) 25 (7), 538-540 (2004). TLC on silica gel with 1) petroleum ether - ethyl acetate - butanone - methanol - water 15:25:3:7:1; 2) petroleum ether - ethyl acetate - formic acid 15:5:1. Detection 1) under UV light, 2) by spraying with 5 % potassium iodobismuthate solution and heating at 105 ºC for 5 min. Identification by finger print technique. Quantification of betaine by densitometry at 514 nm.

fruits rind by using high-performance thin-layer chromatography. Asian Journal of Chemistry 23(2), 788-790 (2011). A simple HPTLC method has been developed for estimation of beta-carotene in fruit rind of Diplocyclos palmatus (Cucurbitaceae). The rind of fruits was extract with acetone. HPTLC on silica gel with petroleum ether as mobile phase. The hRf value of beta-carotene was 30. Densitometric evaluation at 450 nm. The method was linear in the range of 6-60 ng/band. The recovery was 99.4 % for beta-carotene.

Journal of Pharmacy Research 4(5), 1538-1540 (2011). HPTLC of duloxetine hydrochloride on silica gel with ethyl acetate - carbon tetrachloride - methanol - toluene - glacial acetic acid 20:12:5:35:5. The hRf value was 35. Quantitative determination at 295 nm. The method was found to be linear in the range of 200-600 ng/band with a mean recovery of 100.2 %. The drug was subjected to different stress conditions (acid, alkali, thermal, photolytic, and oxidative) and the degradation products were well resolved from the main drug.

Americ. Lab. 17, (3) 131-133 (1985). TLC of aspartame on silica with butanol - acetic acid - water 6:2:2. Detection by spraying with 0.2 % ninhydrin in acetone. Quantification by densitometry. Visual detection limit 50 ng and lower; limit of determination150 ng (instrument dependent.). Comparison with other methods.

Analyst 115, 263-267 (1990). Evaluation of diazonium reagent Fast Black K salt for visualization of amines and phenols on silica plates. Differentiation between aliphatic primary and secondary amines by color. Determination of the structures of colored reaction products. Detection limit 0.05 – 0.5 µg for various chromatographed drug substances.

A comparative study. J. Chromatogr. 635, 165-170 (1993). Two-dimensional TLC maps of dansyl chloride-, dabsyl chloride- and 7-chloro-4-nitrobenzoxazole - derivatised amines on silica with 9 solvent systems. Evaluation of some factors which influence sensitivity. Recommendation of dansyl chloride as the reagent for chromatographic analysis of complex mixtures of biogenic amines.

Anal. Letters 31, 475-489 (1998). HPTLC of plant tissues, dansylated in a microwave oven, on silica with chloroform - triethylamine 2:1. Quantitation by in situ densitometry at 338/>502 nm. Detection limit 1.8 - 3.0 ng. Precision 0.75-1.39%.