Chromatogr. 26 (1), 61–68 (2012) Picroside-I and picroside-II are known bioactive metabolites in Picrorhiza species. Presentation of a simple, precise method for the simultaneous determination of picrosides (picroside-I and picroside-II) in two different Picrorhiza species, P. kurroa and P. scrophulariiflora. TLC of the extracts of the medicinal herbal drugs on silica gel with chloroform – methanol 22:3. Quantification of picrosides (picroside-I and picroside-II) by absorbance measurement at UV 254 nm. Comparative study revealed that the content of picroside-I and picroside-II is higher in P. scrophulariiflora than P. kurroa the content of picroside-I was found to be 1.3 and 1.6 % inP. kurroa and P. scrophulariiflora, and of picroside-II 0.5 and 0.6 %, respectively. Study of the antioxidant potential of the two Picrorhiza species using DPPH* radical reagent. The scavenging activities of P. kurroa and P. scrophulariiflora were 37.7 % and 34.3 %, respectively, at a concentration of 0.1 mg/mL.

J. Planar Chromatogr. 26, 137-140 (2013). HPTLC of glucose (1) and maltose (2) in the digestive gland-gonad complex of Biomphalaria glabrata snails on silica gel with 1-butanol - glacial acetic acid - diethyl ether - water 27:18:5:3. Detection by spraying with alpha-naphthol-sulfuric acid detection reagent followed by heating at 110 °C for 10 min. The hRf values of (1) and (2) were 41 and 28, respectively.

J. Planar Chromatogr. 25, 168-173 (2012). HPTLC of arbutin in commercial whitening creams with methanol - chloroform - acetic acid 7:12:1. Quantitative determination by absorbance measurement at 254 nm. The hRf value of arbutin was 40. LOD and LOQ were found to be 42 and 112 ng/zone, respectively.

Chinese J. of Lishizhen Trad. Med. & Pharm. 22 (3), 620-621 (2011). Superpressure jet flow processing technology has been recently applied in puffing of some traditional Chinese medicinal herbs like Aconitum carmichaeli Debx. The effect of the technology on the traditional Chinese medicinal preparations containing Aconitum carmichaeli Debx was studied by determination of the content change of the active components. TLC of the extracts before and after superpressure jet flow processing on silica gel with chloroform – acetone – methanol 6:1:1. Detection by spraying with 5 % potassium iodobismuthate solution and evaluation under UV 366 nm. Identification of aconitine by comparison with the standards.

J. Liq. Chromatogr. Relat. Technol. 36, 2378-2386 (2013). 2D-HPTLC of testosterone (1), progesterone (2), hydrocortison (3), estriol (4), ethinylestradiol (5), sitosterol (6), estrone (7), prednisolone (8), estradiol (9) and norethindrone (10) in waste water on cyanopropyl silica gel with dichloromethane - methanol - cyclohexane 19:1:12 in the first direction and water - acetonitrile - ethanol - dioxane 8:2:1:1+1 drop ammonia in the second direction. Detection by heating at 110 °C for 1 min followed by dipping into a mixture of sulfuric acid 98 % - water 1:49 and heating at 110°C for 10 min. Quantitative determination by absorbance measurement at 366 nm. The hRf values for the first and second direction were 80 and 5 for (1), 72 and 9 for (2), 32 and 21 for (3), 8 and 31 for (4), 31 and 11 for (5), 80 and 0 for (6), 44 and 12 for (7), 12 and 34 for (8), 71 and 1 for (9) and 62 and 16 for (10). LOD and LOQ for 17alpha-ethinylestradiol were 1 and 2 ng/zone, respectively.

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).

J. Planar Chromatogr. 26, 279-283 (2013). HPTLC of oleandrin in the stems of Nerium oleander on silica gel with n-hexane - ethyl acetate 2:3. Quantitative determination by absorbance measurement at 275 nm. The hRf of oleandrin was 24. Linearity was in the range of 2-75 ng/zone. LOD and LOQ were 2.2 and 6.7 ng/zone, respectively. Relative recoveries in serum and urine were 83 and 89 %, respectively. Intermediate/interday/intra-day precision was below 9 %.

Food Control. 31, 218-223 (2013). HPTLC of aflatoxin B1 (AFB1) on silica gel with chloroform - acetone 9:1. Quantitative determination by fluorescence measurement at 366 nm. The method allowed for determination of inhibitory effect of essential oils on AFB-1 production by A. flavus.