Research J. Pharm. and Tech. 3(2), 559-561 (2010). TLC on silica gel with toluene - acetonitrile - formic acid 50:50:3 with chamber saturation for 30 min. The hRf value was 27 for perindopril and 55 for losartan. Densitometric evaluation at 212 nm. The method was linear in the range of 5-30 µg/band and 1-10 µg/band for losartan and perindopril respectively. The average recovery was 98.2-99.9 %.

J. Trad. Chinese Veterinary Med. (5), 53-55 (2010). TLC on silica gel with acetone – ethanol – hydrochloric acid 10:6:1. Detection by spraying with bismuth potassium iodide – 1 % FeCl3 in ethanol 5:1 and heating at 100 ºC. Quantitative determination of stachydrine by absorbance measurement at 510 nm. The precision was 3.7 %RSD within plate (n=8), and the stability of the measurement within 120 minutes was 4.5 %RSD (n=5). The linearity range was 3.2-38.3 µg/zone (r=0.997, n=6) and standard addition recovery was 96.6 % (RSD=2.0 %, n=6).

Chinese J. of Heilongjiang Med. 26 (2), 189-190 (2013). Fufang Niaoweoan Diyanye eye drops, i.e. allantoin/vitamin B6/vitamin E/aminoethylsulfonic acid eye drops, are used for treating eye fatigue and dry eye syndrome. For quality control, semiquantitative determination of taurine, the main active ingredient, by TLC on silica gel with n-butanol – ethanol – water – glacial acetic acid 3:1:1:1, detection by spraying with ninhydrin – ethanol 1:1000 and viewing in daylight. Semi-quantification by comparison of the area size and color of the target zone with the standard taurine. The LOD was around 100 ng/zone. The influences of temperature, acidic, alkaline and oxidizing conditions were studied.

J. Chromatogr. Sci. 54 (1), 79-87 (2016). Determination of either linagliptin (LGP), saxagliptin (SGP) or vildagliptin (VGP) in their binary mixtures with metformin (MET) in pharmaceutical preparations by HPTLC on silica gel with methanol – 0.5 % aqueous ammonium sulfate 4:1. Densitometric evaluation at 225 nm for the LGP/MET mixture and at 208 nm for the SGP/MET and VGP/MET mixtures. The linearity was between 50-500 ng/zone for LGP and SGP, 0.2-2 µg/zone for VGP and 5-40 µg/zone for MET, respectively. The relative standard deviation for intra- and interday precision were within 2 %.

J. Chromatogr. Sci. 57 (1), 81–86 (2019). HPTLC of of norfloxacin (NF), tinidazole (TZ) and its potential impurity 2-methyl-5-nitroimidazole (MNZ) on silica gel with chloroform – methanol - formic acid 75:10:3. Detection and quantitative determination by densitometry at 298 nm. The linearity was between 0.4–2.4, 0.4–1.6, and 0.2–1.2 μg/band for NF, TZ and MNZ, respectively.

Anal. Chim. Acta 170, 153-158 (1985). TLC of flunitrazepam and its metabolites in urine on silica with a) chloroform - acetone 85:15 and b) ethyl acetate - ethanol - NH3 100:10:3. Detection by inspecting under UV 254 nm and 365 nm, or fluorescence scanning at 365 nm.

J. Chromatogr. 403, 343-349 (1987). TLC on silica with 1. ethyl acetate - methanol - 25 % NH3 85:10:5, 2. ether - methanol - 25 % NH3 90:9:2, 3. dichloromethane - methanol - 25 % NH3 90:9:1.5, and 4. diisopropyl ether - methanol - 25 % NH3 75:35:1. Detection by drying at 110 °C for 5 min., spraying with 4-methoxybenzaldehyde - sulfuric acid - ethanol 1:1:9 and heating again for 1 min.

Pharm. Anal. 8, 185-186 (1988) (Yaowu Fenxi Zazhi). TLC on silica with chloroform - methanol - dimethyl amide 20:2:1. Quantification by densitometry at 271 nm, 275 nm, resp.