J. Planar Chromatogr. 24, 381-387 (2011). TLC of methanolic extracts (from cigarettes, niswar, tobacco leaves, beedi, and gutka) and nicotin on silica gel with petroleum ether - acetone - diethylamine 19:5:1 in a twin-trough chamber with saturation at 25 +/-3 °C and a relative humidity of 42 +/- 5 %. Quantitative determination by densitometry in absorbance mode at 262 nm. The hRf value of nicotine was 57. Linearity was in the range of 250-1500 ng/zone with r = 0.997. LOD and LOQ were 3 and 10 ng/zone, respectively. The recovery (n = 6) was 98.1- 100.1 %. The precision (%RSD) for repeatability, intra-day and inter-day analysis was below 3 % for three different tobacco samples.

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 %.

J. Planar Chromatogr. 29, 394-396 (2016). HPTLC of 1-(8-bromobenzo[1,2-b;4,5-b′]difuran-4-yl)-2-aminopropane, popularly known as Bromo-DragonFLY on silica gel with methanol – ammonia 200:3. Quantitative determination by absorbance measurement at 281 nm. The hRF value for Bromo-DragonFLY was 50. Linearity was between 6 and 75 μg/zone. The intermediate precisions were below 4.3 % (n=3). The LOD and LOQ were 2.1 and 6.3 μg/zone, respectively. Average recovery was 94.5 %.

J. Planar Chromatogr. 31, 383-388 (2018). HPTLC of cocaine hydrochloride (1) and levamisole hydrochloride (2) on silica gel with cyclohexane – toluene – diphenylamine 75:15:10. Quantitative determination by absorbance measurement at 230 nm. The hRF values for (1) and (2) were 24 and 48, respectively. Linearity was between 200 and 2400 ng/zone for (1) and 100 and 1200 ng/zone for (2). LOD and LOQ were 14 and 42 ng/zone for (1) and 6 and 19 ng/zone for (2), respectively. The intermediate precision was <2 % (n=6). Average recovery was 99.8 % for (1) and 99.9 % for (2).

J.A.O.A.C. 67, 337-339 (1984). HPTLC of aflatoxins B1, B2, G1, G2 on silica with chloroform - acetone 88:12. Quantification by fluorodensitometry. Comparison of the results from HPTLC with those from LC. With respect to precision, accuracy, sensitivity, recovery and linearity of response, HPTLC appears to be equivalent to LC.

Fluorimetric detection and quantitative determination of organic acids - preservatives in food. GIT Suppl. Chromatographie 3, 21-26 (1987). Identification and quantification of propionic, sorbic and benzoic acids isolated from liquid containing food stuffs HPTLC on silica with toluene - ethyl acetate - NH3 80:120:1 following pre-chromatographic derivatization with dansylsemipiperazide + dicyclohexylcarbodiimide. Densitometric scanning by fluorescence; determination limit 10-20 ng.

Biochemical Systematics and Ecology 15, 373-376 (1987). TLC of variabilin on silica with hexane - ethyl acetate 3:1. Detection under UV 254 nm.

Phytochemistry 28, 283-284 (1989). TLC on silica with benzene - nitromethane - acetone 75:25:1, benzene - ethyl acetate - acetone 40:10:1, chloroform - nitromethane 9:1. Detection under UV 254 nm.