Acta Chromatographica 22 (2), 173-187 (2010), DOI:10.1556/AChrom.22.2010.2.2. HPTLC on silica gel with methanol – carbon tetrachloride – ethyl acetate – glacial acetic acid 80:636:280:4. The hRf values were 45 and 30 for atorvastatin calcium and losartan potassium, respectively. Quantification by densitometry at 238 nm. Linearity was in the range of 50–500 ng/band for each substance. The recoveries were 100.6 % and 100.5 % for atorvastatin calcium and losartan potassium, respectively. No interference from excipients was observed. The results were compared statistically using a paired t-test with results by an RP-HPLC method. Both methods provided comparable results.

J. Liq. Chromatogr. Relat. Technol. 32, 3056-3065 (2009). HPTLC of steroid compounds (androsterone, epi-androsterone, dehydroepi-androsterone, testosterone, stigmasterol, ß-sitosterol, estradiol, hydrocortisone, and cholesterol) on RP-18 with methanol - water and acetonitrile - water in different volume compositions. Detection by spraying with sulfuric acid - methanol 1:9, followed by heating at 120 ºC for 15 min. The chromatographic parameters of lipophilicity of the studied steroids were determined.

International Journal of ChemTech Research 2(3), 1372-1375 (2010). TLC of olopatadine hydrochloride on silica gel aluminum foil with methanol - water - glacial acetic acid 40:10:1 with chamber saturation for 20 min. The hRf value was 37. Quantitative determination by densitometry in absorbance mode at 247 nm. The method was linear in the range of 200-1200 ng/band. The average recovery was 100.5 %.

J. Planar Chromatogr. 23, 353-358 (2010). TLC of aclarubicin and doxycycline on silica gel, RP-18, cellulose, polyamide 11, and HPTLC on silica gel and RP-18 with a wide range (from 0 to 100 %) of mixtures of n-alcohols with DMSO, hexamethyldisiloxane, acetonitrile, and water in chambers saturated with mobile phase at room temperature. Detection by spraying with sulfuric acid - methanol 1:4, anisaldehyde - methanol - acetic acid - orthophosphoric acid - sulfuric acid 1:100:10:10:5 (for cellulose) and 5 % aluminium chloride in methanol (for polyamide). The effect of mobile and stationary phases on the chromatographic behavior of the compounds was studied.

Planta Med. 76, 133-136 (2010). TLC of mitraphylline on silica gel with (1) dichloromethane - acetone 5:4, (2) diethyl ether - ethyl acetate 1:1, and (3) dichloromethane - ethanol 19:1. The hRf value in system (1) was 83, in (2) 73, and in (3) 68. Detection by spraying with sulfuric acid - acetic acid - water 1:20:4 followed by heating at 120 °C and by Dragendorff’s reagent.

Ham. Ex D. Don, Myricaceae. J. Planar Chromatogr. 23, 326-331 (2010). HPTLC of myrecitin and stem bark extracts on silica gel with toluene - ethyl acetate - formic acid - methanol 15:15:3:2. Quantitative determination by absorbance measurement at 268 nm. Linearity was between 0.4-2.0 µg/band. The limits of detection and quantitation were 93 ng and 284 ng/zone. The intra-day and inter-day precision of the method was in the range of 0.14-0.55 %. The recovery of myrecitin at three concentrations was in the range of 98.9-100.1 % and the average recovery was 99.3 %.

J. of Chromatogr. A 1218 (33), 5693-5704 (2011) A micro-TLC platform for the fast analysis of low-molecular mass compounds from spirulina samples was developed. The target compounds were extracted with methanol, acetone or tetrahydrofuran. HPTLC on RP-18W with acetone - n-hexane 3:7 in an unsaturated chamber using a temperature controlled micro-planar chromatographic device based on a horizontal chamber. Detection under visible light before and after exposure to iodine vapor. Pictures of the chromatograms were acquired with an office scanner and digitalized. The quantitative data was analyzed using cluster analysis and principal components analysis. With this method it was possible to distinguish genuine spirulina and non-spirulina samples as well as fresh and expired commercial products.

Research J. Pharm. and Tech. 3(4), 1106-1108 (2010). TLC of spironolactone and torsemide in combined tablet dosage form on silica gel with n-hexane - ethyl acetate - methanol - glacial acetic acid 12:6:3:1. Quantitative evaluation by absorbance measurement at 263 nm. The hRf value of spironolactone and torsemide was 67 and 34, respectively. The linearity was in the range of 100-1000 ng/band for both drugs. The method has been successfully applied for the analysis of drugs in pharmaceutical formulation.