Food Chem. 110, 538-546 (2008). TLC of wax esters of oilfish (Ruvettus pretiosus) and escolar (Lepidocybium flavobrunneum) on silica gel with xylene. Detection by spraying with 40 % sulfuric acid in ethanol - anisaldehyde 9:1, followed by heating at 100 °C for 2 min or until color is observed. The hRf value of wax esters was 60. The method was compared with DNA sequencing and GC-MS. The TLC method is inexpensive, provides a reliable result within 30 min, and is suitable for screening of numerous samples.

by HPTLC. Abstract No. 9191, IHCB (2009). HPTLC of (-)hydroxy citric acid (the main constituent of Garcinia gummigutta fruits) on silica gel with n-propanol - water - glacial acetic acid 50:50:1. Quantitative determination by absorbance measurement at 210 nm. The hRf value was 46. The method was linear in the range of 100-1000 ng/spot, recovery was 99.8-100.9 %.

Indian Drugs 47(3), 55-56 (2010). An HPTLC method is described for estimation of n-valeric acid in Valeriana officinalis (Valerianaceae). Methanolic extracts of the plant were subjected to chromatographic analysis on silica gel with toluene - ethyl acetate 3:1. Densitometric evaluation at 254 nm. The method was linear in the range of 500-1500 ng/band with a recovery between 98.4-104.1 %. The plant extract was found to contain 1.13 % of n-valeric acid.

Eurasian J. Anal Chem 4(2), 152-160 (2009). A stability indicating HPTLC method has been reported for estimation of aspirin and clopidogrel bisulphate in combined dosage form. HPTLC on silica gel with carbon tetrachloride - acetone 5:2. The hRf value of aspirin was 13 and of clopidogrel 78. Densitometric evaluation at 220 nm. Linearity was in the range of 200-600 ng/spot for aspirin and 300-600 ng/spot for clopidogrel. Degradation products (acid, base oxidative, dry heat, photodegradation) did not interfer with the analysis.

62nd Indian Pharmaceutical Congress Abstract No. F-241 (2010). TLC of hydrochlorothiazide and telmisartan on silica gel with ethyl acetate – chloroform – methanol 6:3:1. The hRf value was 38 for telmisartan and 55 for hydrochlorothiazide. Quantitative determination by absorbance measurement at 280 nm. The method was found to be linear in the range of 50-600 ng/band for both drugs. The sample was subjected to different stress conditions (acid, alkali, H2O2, thermal, photolytic) and was analyzed by the proposed method. The drugs were well separated from their degradation products. The method can be used for stability studies.

Indian Drugs 48(4), 49-55 (2011). HPTLC of hydrochlorothiazide (HCZ), amlodipine besylate (AMB) and valsartan (VAL) on silica gel with ethyl acetate - methanol - 10 % ammonia 17:4:2. The hRf value was 26 for AMB, 34 for VAL and 82 for HCZ. The linearity range was 100-700 ng/band for VAL and HCZ and 50-400 ng/band for AMB.

Food Res. Int. 54, 1229-1236 (2013). HPTLC of p-coumaric acid in the leaves of Enhalus acoroides (L.f.) Royle, Thalassia hemprichii (Ehrenberg) Ascherson, Halodule pinifolia (Miki) den Hartog, Syringodium isoetifolium (Ascherson) Dandy, Cymodocea serrulata (R. Brown) Ascherson & Magnus and Cymodocea rotundata Ehrenberg & Hemprich ex Ascherson on silica gel with toluene - ethyl acetate - methanol - glacial acetic acid 16:2:1:1. Quantitative determination by absorbance measurement at 254 nm. The hRf value of p-coumaric acid was 42. Linearity was in the range of 100-500 ng/zone. LOD and LOQ were 15 and 45 ng/zone.

J. Planar Chromatogr. 30, 363-374 (2017). HPTLC of acetylsalicylic acid (1) and its related compound salicylic acid (2) on silica gel with n-hexane – diethyl ether – 80 % acetic acid 7:2:1. Good quality densitograms with well separated and symmetric peaks of (1) and (2) were achieved. Detection with the following reagents: Janus blue, bromophenol blue, bromocresol blue, hydrogen peroxide (without heating and with heating to 90 °C during 60 min), 1 % sodium hydroxide (with heating to 45 °C and also with heating to 90 °C during 60 min), brilliant green, malachite green, and thymol blue.