J. Liq. Chromatogr. Relat. Technol. 33, 179-190 (2010). TLC of salicylic acid and its derivatives, namely acetylsalicylic acid, salicylanilide, salicylaldehyde, salicylamide, salicylhydroxamic acid, methyl salicylate, phenyl salicylate, 3,5-dinitrosalicylic acid, 2,5-dihydroxysalicylic acid, 3-aminosalicylic acid, 4-aminosalicylic acid, and 5-aminosalicylic acid, on RP8, RP18 and HPTLC on RP18 and cyano phase with methanol - water; the content of methanol in mobile phase was gradually varied by 5 % from 20-100 %. Development in a chamber saturated for 15 min. Quantitative determination by scanning densitometry in absorption mode at the respective absorption maximum. The hRf values were recalculated on the RM values. The chromatograms were repeated in triplicate and mean hRf values were calculated. The results indicate that the chromatographic parameter of lipophilicity determined on RP8 and cyano phase may be used as a measure of lipophilicity of the investigated salicylic acid and its derivatives.

J. Liq. Chromatogr. Relat. Technol. 33, 423-430 (2010). HPTLC of olmesartan and zidovidine on silica gel with ethyl acetate - methanol - acetic acid 160:40:1 in a twin-trough chamber saturated for 10 min. Quantitative determination by densitometric scanning at 269 nm. The linearity range was 80-600 ng/zone. LOQ was 80 ng/zone, the correlation coefficient 0.9900 and 0.9820. Recovery was 90.1 and 79.6 %. The accuracy and precision of the method were determined by repeatability (intra-day) and intermediate precision (inter-day) for the set of quality control samples (low, mid, high) in replicate. The results revealed excellent intra- and inter-day accuracy and precision of the method, which was within the acceptable limit (accuracy (% RE) 11.89 and 6.76 (low), 2.53 and 3.83 (mid), and 0.65 and 7.14 (high); inter-day precision (CV): 3.29 and 3.00 (low), 1.02 and 1.51 (mid), and 1.11 and 0.69 (high); intra-day precision: 2.59 and 2.86 (low), 1.07 and 1.13 (mid), and 1.04 and 0.72 (high) - after LLE and SPE, respectively).

Journal of Pharmacy Research 3(11) (2010). TLC on silica gel (plates pre-washed with methanol) with chloroform - isopropanol - toluene 8:1:1. The hRf value was 22. Densitometric evaluation at 254 nm. The method was linear in the range of 100-5000 ng/band. The recovery was in the range of 99.8-101.5 %.

Scholars Research Library 2(2), 328-332 (2010). A validated densitometric method has been development for simultaneous estimation of drotaverine and aceclofenac in combined dosage form. TLC on silica gel with methanol - ethyl acetate - glacial acetic acid 100:90:1. The hRf value of drotaverine was 18 and of aceclofenac 51. Densitometric evaluation at 300 nm. The method was linear in the range of 80-360 ng/band for drotaverine and 100-700 ng/band for aceclofenac. The average recovery was 99.8-100.2 %.

Research J. Pharm. and Tech. 3(4), 1275-1278 (2010). A stability indicating HPTLC method has been developed for ofloxacin. The results were confirmed by bioautography. HPTLC on silica gel with n-butanol - ethanol - 25 % ammonia 5:5:4. The hRf value was 53. Densitometric evaluation at 299 nm. The method was linear in the range of 500-2500 ng/band. The sample was subjected to forced degradation (acid, base, oxidation, thermal, photolytic) and both degraded and un-degraded sample were analyzed by HPTLC and bioautography. The result obtained by bioautography confirmed that the antimicrobial activity of ofloxacin was directly related to its degree of degradation under different stress conditions. Further no inhibition zone was observed at another hRf than that of ofloxacin, which indicates that degradation products do not exhibit antibacterial activity. Bioautography studies were carried out in petri plates (10 cm diameter) using as media Mueller Hinton agar and as organism Escherichia coli NCIM 2066.

Biochem. Biophys. Res. Commun. 399, 716-720 (2010). HPTLC of globotriaosylceramide (Gb3) in mouse tissues on silica gel with chloroform - methanol - water 65:25:4. Detection by HPTLC-immunostaining with an anti-Gb3 monoclonal antibody. Quantification by densitometry with a luminescent image analyzer. The limit of detection of Gb3 was 50 ng/zone.

Analytical Chemistry - An Indian Journal 8(1), 77-81 (2009). An HPTLC method is reported for estimation of lupeol and beta-sitosterol in the whole plant powder of Asteracantha longifolia (Acanthaceae). The proposed method was also employed for estimation of beta-sitosterol in herbal formulation containing Asteracantha longifolia. Methanolic extracts of the sample were used for chromatography. HPTLC on silica gel with toluene - ethyl acetate - methanol 75:15:7. Derivatization with Liebermann-Burchard reagent. Densitometric quantification at 366 nm. The concentration of lupeol and beta-sitosterol was 0.162 mg/g and 0.045 mg/g, respectively in the whole plant, while the concentration of beta-sitosterol was 0.039-0.048 mg/g in the formulation. The method was suitable for the quality control of the herbal formulation.

Indian Drugs 47(5), 42-45 (2010). HPTLC of lamivudine and zidovudine on silica gel with acetone - toluene - methanol 2:1:2. The hRf of lamivudine was 34 and of zidovudine 74. Densitometric quantification at 267 nm for zidovudine and 272 nm for lamivudine. The method was linear in the range of 10-210 ng/band for lamivudine and 30-420 ng/band for zidovudine. The recovery was between 99.5-100.4 % for the compounds. The method is suitable for estimation of compounds in combined formulations.