Analytical Methods 2, 521-531 (2010). An HPTLC method for determination for paliperidone in formulation as well as for in vitro release studies has been developed. HPTLC on silica gel with methanol - ethyl acetate 4:1. The hRf value was 54. Quantification was performed by densitometric evaluation at 254 nm. The method was linear in the range of 100-600 ng/band. The method was suitable for estimation of the drug in mucoadhesive microemulsion formulations, as well as for solubility and diffusion studies.

Research Journal of Pharmaceutical, Biological and Chemical Sciences 1(2), 226-234 (2010). TLC on silica gel with toluene - isopropanol - 25 % ammonia 23:23:4. The hRf value was 30. Densitometric evaluation at 258 nm. The linearity range was 100-350 ng/band. For stability studies diacerein was subjected to different stress conditions (acid, alcohol, oxidative, thermal, photolytic). Degradation products were well resolved from the main zone of diacerein with significantly different hRf values.

Scholars Research Library 2(1), 489-494 (2010). HPTLC of montelukast sodium and levocetirizine dihydrochloride on silica gel with toluene - chloroform - methanol - glacial acetic acid 6:20:10:1 in a twin trough chamber with chamber saturation for 25 min. The hRf value of levocetirizine was 64 and of montelukast 89. Densitometric evaluation at 302 nm. The method was linear in the range of 200-3200 ng/band for montelukast and 400-1200 ng/band for levocetirizine. The recovery was 99.9-100.0 %.

Research Journal of Pharmaceutical, Biological and Chemical Sciences 1(4), 152-157 (2010). TLC on silica gel with methanol - 10 mM ammonium acetate 3:2 . The hRf value of ranolazine was 49. Densitometric evaluation at 271 nm. The method was linear in the range of 1-6 µg/band with a mean recovery of 100.0 %.

Eurasian J. Anal. Chem. 4(1), 87-97 (2009). HPTLC of rabeprazole sodium on silica gel with acetone - water 7:30. The hRf value was 45. Densitometric quantification at 284 nm. Linearity was in the range of 400-2400 ng/band. The recovery was 99.6-101.4 %. The sample was subjected to forced degradation (acid, alkali, oxidative, thermal, photolytic). The degradation products were well separated from the main compound and the method is suitable for stability studies.

J. Chromatogr. Sci. 49, 129-135 (2011). TLC of hydrochlorothiazide (HCT), spironolactone (SPR) and their impurities and degradation products on silica gel with ethyl acetate - chloroform - formic acid - triethyl amine 70:30:1:1. Quantification by densitometry. The different method parameters were optimized for maximum separation. The method was applied for determination of HCT and SPR in commercial tablets. Statistical comparison with the also performed HPLC method showed that there is no significant difference in the performance of the methods.

J. Chromatogr. Sci. 48, 68-75 (2010). TLC of cefaclor, cefadroxil, cefalexin and cefradine on silica gel with ethyl acetate - methanol - water in different ratios. The studied drugs had hRf values between 40 and 60. Detection of blue to violet colored zones after spraying with ninhydrin reagent. Quantification by densitometry. Linearity was in the range of 2-10 µg/zone with correlation coefficients ranging from 0.9990 to 0.9996 and determination coefficients from 0.9986 to 0.9992 for all studied drugs. The limits of detection and quantification for all studied drugs were between 90 to 230 ng/zone and 270 to 840 ng/zone, respectively.

Food Research International 44, 1088-1093 (2011). HPTLC of resveratrol (1) and the resveratrol complex with hydrogenated soy phosphatidyl choline (2) on silica gel with dichloromethane – methanol 4:1. The hRf values of (1) and (2) were 87 and 92, respectively.