J. Sep. Sci. 41, 3553-3560 (2018). HPTLC of sofosbuvir (1), daclatasvir (2), and ledipasvir (3) on silica gel with methylene – chloride – methanol – ethyl acetate – ammonia (25 %) 6:1:4:1. Quantitative determination by absorbance measurement at 275 nm. The hRF values for (1) to (3) were 27, 50 and 68, respectively. Linearity ranged between 100-3000 ng/zone for (1) and (2) and 50-3000 ng/zone for (3). LOD and LOQ were 23 and 68 ng/mL for (1), 32 and 96 ng/mL for (2) and 16 and 48 ng/mL for (3). The intermediate precision was <2 % (n=3). Average recovery was 99.5 % for (1), 99.5 % for (2) and 99.7 % for (3).

J. Planar Chromatogr. 31, 389-395 (2018). HPTLC of paracetamol (1), pamabrom (2), and pyrilamine maleate (3) on silica gel with chloroform ‒ acetonitrile 3:7. Quantitative determination by absorbance measurement at 275 nm. The hRF values for (1) to (3) were 76, 46 and 12, respectively. Linearity ranged between 10-280 ng/zone for (1), 5-45 ng/zone for (2) and 1-20 ng/zone for (3). The intermediate precision was <2 % (n=3). The recovery was between 99.2 and 100.4 %.

CBS 90, 6-7 (2003). HPTLC phospholipids and glycolipids from rape seed on lichrospher silica gel with chloroform - methanol - acetone - water 18:15:2:1 for phospholipid separation and with acetone - chloroform - water 30:15:2 for glycolipid separation, developing distance 70 mm each. Detection by dipping in molybdatophosphoric acid reagent (5 % in ethanol) followed by heating at 120 °C for 15 min. Quantitative determination by absorbance measurement at 720 nm.

CBS 85, 10-11 (2000) HPTLC-AMD of water samples on silica gel with 33-step gradient from acetonitrile - ammonia to dichloromethane and dichloromethane - acetic acid to n-hexane. Detection via Chrom Biodip (Merck) by dipping in bacteria solution (Bacillus subtilis) followed by incubation at 30 °C over night and spraying with MTT-tetrazolium salt reagent followed by incubation at 30 °C for 5-30 min. Visual evaluation.

CBS 86, 7 (2001). HPTLC on silica gel in horizontal development chamber with acetone - water 9:1 with chamber saturation for 15 min. Detection by dipping 1 s in 0.02 % 4-nitrosodimethylaniline in ethanol with 0.01 N HCl (adjusted at pH 2) followed by heating at 150 °C. Quantitative determination by absorbance measurement at 495 nm.

J. Liq. Chrom. Rel. Technol. 27, 2039-2045 (2004). HPTLC of cholesteryl oleate, methyl oleate, triolein, oleic acid, and cholesterol on pre-washed silica gel with petroleum ether - diethyl ether - glacial acetic acid 80:20:1 in a twin-trough chamber with saturation. Detection with phosphomolybdic acid reagent. Quantitative determination at 610 nm.

Indian Drugs 41 (8), 482-487 (2004). HPTLC on silica gel with toluene - acetone - ammonia 50:50:1. Quantitative determination by absorbance measurement at 315 nm. The method was validated in terms of linearity (300-1000 ng/spot), precision, accuracy, and specificity. For the content uniformity test the tizanidine hydrochloride content of 10 individual tablet units of two market formulations was determined after extracting with methanol. Both formulations compiled with the USP specification. The proposed content uniformity allows the parallel analysis of ten tablets on a single plate and provides a faster and cost-effective quality control tool for routine analysis. A simple, sensitive HPTLC content uniformity test was developed and validated for the analysis of tizanidine hydrochloride in its commercial single component tablet formulations (2 mg/tablet).

J. Planar Chromatogr. 17, 286-289 (2004). HPTLC of isoquercitrin, avicularin, rutin, apigenin 7-glucoside, naringin, and hesperidin on silica gel with ethyl acetate - methanol - formic acid 90:10:1. Detection under UV light at 254 nm and by spraying with 1 % methanolic diphenylboric acid beta-ethylamine ester, followed by spraying with 5 % ethanolic polyethylene glycol 4000. Quantitative determination by densitometry at 254 nm. Report of the possibilities and advantages of HPTLC for investigation of hydrolysis.