Planta Medica 83(03/04), 239-244 (2017). HPTLC of flavokawin B (purity checked by TLC, followed by sulfuric acid detection) and a hexane maceration of Polygonum ferrugineum aerial parts on silica gel, twice in the same direction with n-hexane – ethyl acetate 4:1 (humidity 33 %). Detection of flavokawin B by densitometry at 366 nm (without derivatization). The hRf value was 53. The content of flavokawin B was 13.6 % in the hexane extract and 1.0 % in the dried plant.

Detection by spraying with 20 % molybdophosphate solution.

J. Chinese Herb Med. (Zhongcaoyao) 21, 61-62 (1990). TLC of sinapine on silica with butanol – ethanol – acetic acid – water 3:1:1:1. Quantification by fluorodensitometry with 313 nm excitation.

J. Planar Chromatogr. 11, 417-420 (1998). TLC determination of formaldehyde (as formaldemethone) with chloroform - dichloromethane (1:3). Application of the HCHO extracts under nitrogen. Quantitation by densitometry at 275 nm. The procedure described for preparation of samples of biological material for TLC analysis enables accurate determination of HCHO levels despite the small amounts present in these samples. The procedure could also be used for quantitative TLC determination of HCHO precursors in cell metabolism in biological material.

J. Planar Chromatogr. 26, 73-77 (2013). TLC of guaifenesin (1), pseudoephedrine hydrochloride (2) and guaiacol (3) on silica gel with hexane - ethyl acetate - acetone - water - triethylamine 30:30:40:3:1. Quantitative determination by absorbance measurement at 208 nm for (1) and (2) and 278 nm for (3). The hRf values for (1) to (3) were 34, 12 and 83, respectively. Linearity was in the range of 2-12 µg/zone for (1), 14-25 µg/zone for (2) and 0.1-1.1 µg/zone for (3). LOD and LOQ were established for (3) only: LOD was 40 ng/zone and LOQ 100 ng/zone. Recovery (by standard addition) was between 99.9 and 100.0 %. Intermediate/interday/intra-day precision was below 2 % (n=3).

Planta Med. 83, 912-920 (2017). Two subfractions of the ethanol extract of Aristolochia cordigera roots were mixed and submitted to preparative TLC on silica gel with hexanes (mixture of hexane isomers) – ethyl acetate 3:2 to isolate hyrtiosulawesine, aristolochic acids I and IV, sodium aristolochates I and IVa. The same method applied to a subfraction of the acetone extract of the roots revealed hyrtiosulawesine and 3,4-dihydro-hyrtiosulawesine.

J. Agric. Food Chem. 34, 319-326 (1986). TLC of the hydrocarbons from chestnut honey extraction, the epoxides of the oleinic components on silica with hexane - ether 95:5 or 90:10. Detection after spraying with 0.2 % ethanolic solution of 2,7'-dichlorofluorescein sodium salt. Extraction and determination with GC and GC/MS.

J. Liquid Chromatogr. 12, 979-985 (1989). TLC of some carboxy and hydroxy benzene derivatives related to lignin and humic materials on silica and Fe(III)- impregnated silica with 1) ethyl acetate, 2) ethyl acetate – benzene 9:11 and 3) ethyl acetate – benzene 5:15. Identification of the compounds tested by the mobility differences on impregnated and plain plates.