J. Chromatogr. A 1459, 145-151 (2016). Presentation of a novel method for coupling TLC with ion mobility spectrometry (IMS) using laser desorption technique (LD). Sampling of the compounds (explosives like trinitrotoluene, 1,3,5-trinitro-1,3,5-triazacyclohexane, pentaerythritol tetranitrate, 2,4-dinitrotoluene and 3,4-dinitrotoluene; amino acids like alanine, proline and isoleucine, nicotine and diphenylamine mixtures) on the layer surface within less than 80 s after TLC separation by using the LD-IMS technique without the need of any further manipulation or preparation. The TLC plate was moved in desired directions by the motorized micro-positioning stage towards the right position of the fixed laser. TLC-LD-IMS offers an additional separation dimension, allowing separation of overlapping TLC analytes, and reveals possibility for fast and effective analysis of the mixtures due to the scan rate for LD being adjustable.

pulegioides and peppermint oil by thin-layer chromatography with densitometry. J. Liquid Chromatogr. 6, 1175-1182 (1983). TLC of pulegone on silica with hexane - ethyl acetate 5:2. Detection by spraying with acetic acid - sulfuric acid-anisaldehyde 100:2:1 and heating at 100 °C for 5 minutes.

J. Chinese Herb Med. (Zhongcaoyao) 21, 105-106, 116 (1990). TLC of resibufogenin, muscone and borneol on silica with chloroform - acetone - cyclohexane 3:3:4. Detection by 5% phosphomolybdic acid in ethanol. Quantification by densitometry at different wavelengths.

J. Agric. Food Chem. 46, 4102-4106 (1998). TLC of 13 carotenoids (i.a. phytoene, phytofluene, zeta-carotene, neurosporane, b-carotene, lycopene, prolycopene, monoepoxy-b-carotene, b-cryptoxanthin, b-citraurin, antheroxanthin, violaxanthin, neoxanthin) on silica gel, magnesium oxide/Kieselguhr 1:1 plates, silica gel containing sodium hydroxide using petroleum ether, ether, and petroleum ether - acetone 90:10. Visualization under UV.

Food Res. Int. 40, 167-175 (2007). HPTLC of absinthin in absinthe beverage (from the wormwood plant Artemisia absinthium L.) on silica gel with acetone - acetic acid (98 %) – toluene – dichloromethane 1:1:3:5. Detection by dipping into a solution of acetic anhydride – sulphuric acid – ethanol 1:1:10, followed by heating for 5 min at 104 °C. Quantitative determination by absorbance measurement at 554 nm. The hRf value of absinthin was 64 and selectivity regarding matrix was given. Linearity was between 0.1 and 10 g/L. The precision was better than 13.5 % (intraday) and 15.8 % (interday). The limit of detection and quantification for absinthin was 0.05 and 0.11 g/L, respectively.

J. Planar Chromatogr. 26, 475-479 (2013). HPTLC of beta-amyrin in the aerial parts of Maytenus obscura and Maytenus parviflora on silica gel with hexane - ethyl acetate 3:1. Detection by spraying with p-anisaldehyde, followed by heating at 105 ºC for 10 min. Quantification by absorbance measurement at 550 nm. The hRf of beta-amyrin was 38. Linearity was in the range of 10-100 ng/zone. LOD and LOQ were 9 and 27 ng/zone. Recovery was in the range of 99.3-99.7 %. Intermediate/interday/intra-day precision was below 2 % (n=6).

Don using a validated high-performance thin-layer chromatographic method. J. Planar Chromatogr. 31, 220-229 (2018). Quantitative TLC of betulin (1), lupeol (2), oleanolic acid (3), and betulinic acid (4) in the bark, leaves, and roots of Betula utilis on silica gel with n-hexane ‒ ethyl acetate 4:1 for (1) to (3), and with toluene – ethyl acetate 7:3 for (4). (1) to (3) were detected by dipping into ceric ammonium sulfate reagent, followed by heating at 105–110 °C for 5 min. Compound (4) was detected by spraying with Liebermann‒Burchard reagent, followed by heating at 105–110 °C for 5 min. Quantitative determination by absorbance measurement at 500 nm for (1) to (3) and 550 nm for (4). The hRf values for (1) to (4) were 59, 71, 48 and 71, respectively. Linearity was in the range of 2.5-10 μg/zone for (1) to (4). The intermediate precision was below 4 %. The LOD and LOQ were 175 and 532 ng/zone for (1), 166 and 504 ng/zone for (2), 396 and 1201 ng/zone for (3) and 109 and 330 ng/zone for (4), respectively. Average recoveries for (1) to (4) were 98.9, 99.3, 99.3 and 99.2 %, respectively.

Journal of Natural Products 50, 49-54 (1987). TLC of quadrone, quadrone-4-ethylene ketal, 8a-hydroxyquadrone, 8a-hydroxyquadrone-4-ethylene ketal on silica with chloroform - acetone - benzene - formic acid 95:5:5:1 and chloroform - ethyl acetate 3:1. Visualization by spraying with p-anisaldehyde - acetic acid - sulfuric acid 1:120:1 and heating.