GIT Fachz. Lab. 1, 14-18 (1999). TLC of hydroxybenzenes (pyrocatechol, resorcinol, phloroglucinol, hydroquinone, and pyrogallol) on conventional silica gel and specific Raman-TLC plates (coated with spherical silica gel) with toluene - methanol - acetic acid 45:16:4 in a saturated chamber. The spectra obtained by Raman spectroscopy enabled the use of data banks for the identification of substances. Typical detection limits are in the low microgram region per application.

J. Agric. Food Chem. 51, 4442-4449 (2003). TLC and preparative TLC of phenolic compounds, e.g. a. rosmarinic acid, on silica gel with chloroform - methanol - water 13:7: 2. Detection after drying by spraying with 2.5% iron(III) chloride solution.

J. Liq. Chromatogr. Relat. Technol. 29, 1125-1142 (2006). (HP)TLC of polyphenols (hydroxybenzoic acids, hydroxycinnamic acids, flavonols, flavones, flavanones); e. g. HPTLC of flavonoids on silica gel with tetrahydrofuran - toluene - formic acid - water 16:8:2:1 in a saturated twin-trough chamber; detection by dipping the warm plate into natural products reagent followed by dipping into PEG 400 solution. Evaluation under UV 254 and 366 nm; densitometry at 254 nm.

czern and Brassica nigra L. Asian J. Chem. 22(7), 5349-5354 (2010). An HPTLC method is reported for estimation of sinigrin from seeds of Brassica juncea and Brassica nigra (Cruciferae). HPTLC of methanolic seed extracts on silica gel with ethyl acetate - methanol - water 6:2:1. Densitometric evaluation at 230 nm. The method was linear in the range of 400-1200 ng/band. Amounts of 0.43 and 1.55 % sinigrin were found in Brassica juncea and B. nigra, respectively. The method is suitable for routine quality control of herbal raw material.

J. Planar Chromatogr. 27, 260-266 (2014). HPTLC of cichoric acid (1), chlorogenic acid (2) and echinacoside (3) in commercial Echinacea products on silica gel with ethyl acetate - formic acid - acetic acid - water 100:11:11:17. Quantitative determination by absorbance measurement at 254 and 366 nm. The hRF values for (1) to (3) were 80, 50 and 32, respectively. Linearity was in the range of 500-3500 ng/zone for (1), 100-700 ng/zone for (2) and 200-1200 ng/zone for (3). The intermediate/interday/intra-day precisions were between 4-12 % (n=3). The LOD and LOQ were 300 and 600 ng/zone for (1), 20 and 60 ng/zone for (2) and 98 and 123 ng/zone for (3), respectively.

Phytochemistry. 117, 554-568 (2015). Review of the bioactive markers for quality control of products containing gingerols and shogaols from the rhizomes of ginger (Zingiber officinale). HPTLC of gingerol in ginger rhizomes and Ayurvedic products on silica gel with n-hexane - diethyl ether 2:3 (1) or n-hexane - acetone 18:7 (2). The hRF value of gingerol was 40 with (1) and 23 with (2).

Hawksw & P. James. Quim. Nova. 39, 456-461 (2016). HPTLC of chloratranorin (1), atranorin (2), ursolic acid (3), 2'-O-methylphysodone (4), physodic acid (5), physodalic acid (6) and physodic acid (7) in Hypogymnia tavaresii on silica gel with toluene – acetic acid 17:3. Detection by spraying with sulfuric acid – acetic acid – water 1:20:4, followed by heating at 120 °C for 20 min. The hRF values of compunds (1) to (7) were 76, 74, 49, 33, 20, 19 and 18, respectively.

and Cassia angustifolia Vahl. J. Planar Chromatogr. 30, 238-244 (2017). HPTLC fingerprint of sennoside A and B in Cassia senna L. and Cassia angustifolia on silica gel with 1-propanol ‒ ethyl acetate ‒ water 4:4:3. Detection by heating at 110 °C for 10 min, followed by spraying with 50 g/L potassium hydroxide in ethanol 50 % and heating again at 110 °C for 10 min. Qualitative determination at UV 366 nm.