J. Planar Chromatogr. 13, 382-384 (2000). HPTLC of acetylsalicylic and salicylic acid on silica gel with ethyl acetate -methanol - acetic acid 80:19:1. Quantitation by densitometry at 300 nm. Information on selectivity, calibration and working range, accuracy and repeatability is also given. Rapid, simple, and accurate method.

J. Planar Chromatogr. 15, 200-203 (2002). TLC of sixteen 2-benzylsulfanyl derivatives of 4-pyridine carbonitrile and of fourteen 2-benzylsulfanyl derivatives of 4-pyridinecarbothioamide on silica gel impregnated by overnight development with diethyl ether - silicone oil 19:1. The aqueous component of the mobile phase was 0.05 M phosphate buffer, pH 7.4, prepared from 0.05 M potassium dihydrogen phosphate and 10% potassium hydroxide. The organic modifier in the mobile phase was acetonitrile or methanol; development at room temperature in a normal chamber equilibrated for 2 h. Detection under UV 254 nm. RP-TLC is considered as a powerful method for determination of the lipophilicity of newly synthesized substances.

J. Liqu. Chromatogr. 25, 927-935 (2002). TLC of polymyxin B sulfate, neomycin sulfate, and bacitracin zinc on silica gel with methanol - ethanol - dichloromethane - NH3 - water 6:6:4:4:3 or methanol - isopropanol - dichloromethane - NH3 - water 8:4:4:4:3. Detection by spraying with a 0.2% solution of ninhydrin in 1-butanol and heating at 105°C for approximately 5 min. New simple and robust method.

J. Planar Chromatogr. 15, 458-462 (2002). TLC of prenylamine, lidoflazine, bepridil, and fendiline on silica gel, alumina, and florisil with several mobile phases comprising mixtures of n-hexane with polar modifiers such as dioxane, ethyl acetate, methanol, ethyl methyl ketone, tetrahydrofuran, and propan-2-ol. Plates were developed in horizontal chambers and visualized under UV 254 nm, by use of a videoscanning system and by use of different reagents. The best separation was achieved on alumina with tetrahydrofuran - hexane 1:4.

Proc. Intern. Symp. on Planar Separations Plan. Chrom. 363-368 (2003). HPTLC of triazine derivatives (2,4-bis(cyclopropylamino)-6-chloro-s-triazine, 2,4-bis(cyclo-dodecyl-amino)-6-chloro-s-triazine) on RP-18 and on silica gel, impregnated with paraffin oil, with water - acetone. Visualization under UV 254 nm.

J. Planar Chromatogr. 16, 447-450 (2003). HPTLC of satranidazole and metronidazole on silica gel, prewashed with methanol, with chloroform - methanol 20:1 after equilibration for 10 min at 20°C. Visualization and quantitation by densitometry at 317 nm. Linearity of satranidazole between 200 and 1000 ng. Simple, specific, and sensitive TLC method.

INDIAN DRUGS 41(1), 32-35, 2004. HPTLC on silica gel 60 F254 aluminium foil with toluene - methanol - chloroform 4:5:11 with chamber saturation for 30 min at room temperature. Rf of amlodipine besylate and losartan potassium was found to be 0.14 and 0.32, respectively. Quantification by densitometry at 245 nm via linear regression for amlodipine besylate between 0.05 to 0.10 µg and for losartan potassium between 0.5 to 1 µg. Validation regarding to accuracy and precision was performed. The limit of detection and limit of quantification for amlodipine besylate was found to be 0.01 and 0.03 ng/µL - for losartan potassium it was 0.004 and 0.013 ng/µL. The average recovery was determined to be 101.15% for amlodipine besylate and 100.74% for losartan potassium.

Indian Drugs 41 (3), 160-164 (2004). Combinations of ofloxacin and tinidazole (1:3) are available as tablet dosage forms. Stability indicating HPTLC of ofloxacin and tinidazole on silica gel with dioxan - ethyl acetate - toluene - acetic acid - water 5.5:5:3.2:2:2 . Quantification by absorbance measurement at 307 nm. The Rf value of ofloxacin and tinidazole was found to be 0.12 and 0.85 respectively. Recovery was 99.85 % and 99.45 % for ofloxacin and tinidazole respectively. The proposed method was quantitatively evaluated in terms of calibration of concentration range, stability, and accuracy. It can be adopted for routine analysis of the formulation.