Research Journal Pharm and Tech. 2(4),746-748 (2009). A validated HPTLC method is reported for simultaneous estimation of nebivolol hydrochloride and valsartan in combined dosage form. HPTLC on silica gel with ethyl acetate - methanol - 25 % ammonia. The hRf value of valsartan was 27 and of nebivolol 75.The method was linear in the range of 800-2400 ng/band for nebivolol and 200-1000 ng/band for valsartan. Densitometric quantification at 280 nm. The method was found suitable for routine quality control of the combined dosage form.

Chinese J. Chromatogr. 26 (1), 50-55 (2008). TLC of some endophytic fungi isolated by column chromatography from selected medicinal plants on silica gel plates with 1) chloroform - methanol 7:1, 2) chloroform - acetonitrile 7:3, 3) ethyl acetate - 2-propanol 19:1, 4) methylene chloride - tetrahydrofuran 3:1, 5) methylene chloride - methanol - dimethylformamide 90:9:1. Detection by spraying with 1 % vanillin sulfuric acid reagent after gentle heating. Also HPTLC on silica gel with chloroform - methanol 9:1. Detection by densitometry at 254 nm and 366 nm. If taxol was present, derivatization by spraying with 1 % vanillin sulfuric acid reagent and heating for 2 min, then detection under UV 366 nm and white light. Only 13 fungal species produced taxol in the artificial culture medium of the 20 screened fungi.

Indian J. Pharma. Educ. Res. 44(4), 341-344 (2010). HPTLC of silica gel with toluene - ethyl acetate - methanol - formic acid 5:16:21. The hRf value was 51. Densitometric evaluation at 220 nm. The method was linear in the range of 300-1800 ng/band. The sample was subjected to different stress conditions (acid, base, oxidative, thermal, and photolytic). Degradation products were well separated from trandolapril, therefore the method can be used for stability studies.

J. Chromatogr. A 1218 (19), 2754-2774 (2011). HPTLC for lipid analysis is particularly useful for smaller, apolar compounds and offers some advantages over HPLC. Description of stationary phases, solvent systems and detection methods for the individual lipid classes (cholesterol and its derivates, glycerides, sphingo- and glycolipids, phospholipids). In comparison with common staining methods the combination of HPTLC and mass spectrometric detection methods is a very powerful method to investigate the identities of the HPTLC zones in detail.

Quim. Nova. 34, 330-334 (2011). TLC of rosmarinic acid in preparations of Rosmarinus officinalis on silica gel with acetone – formic acid – methylene chloride 50:17:170. Detection under UV 366 nm. Quantitative determination by solid state differential pulse voltammetry (DPV). Linearity was between 0.694x10-3 to 0.526x10-3 mol/L. The limits of detection and quantification were 1.2x10-5 and 3.6x10-5 mol/L, respectively. The intermediate/interday/intraday precisions were 3.03 % and 2.2 %, respectively. Recovery (by standard addition) was 96.3 % for rosmarinic acid. The method presented high recovery levels compared to an HPLC method.

J. Ethnopharmacol. 134, 992-995 (2011). HPTLC of fumaric acid and fumaric acid conjugates (as dimethyl fumarate) in the aerial parts of Fumaria indica on silica gel with formic acid – chloroform – butanol – heptane 3:4:8:11. Quantitative determination by absorbance measurement at 260 nm.

62nd Indian Pharmaceutical Congress Abstract No. F-290 (2010). TLC of ranolazine on silica gel with methanol – 10 mM ammonium acetate 3:2. The hRf value was 54. Quantitative determination by absorbance measurement at 271 nm. The recovery was 99.9 %.

62nd Indian Pharmaceutical Congress Abstract No. F-261 (2010). TLC of montelukast sodium and levocetirizine dihydrochloride on silica gel with ethyl acetate – methanol – ammonia 10:2:1. Quantitative determination by absorbance measurement at 231 nm. Montelukast and levocetirizine were subjected to acid, base, peroxide, and photodegradation. In stability tests the drugs were susceptible to acid and basic hydrolysis, oxidation and photolytic degradation. The stressed samples were analyzed by the proposed method and no intereference of the degradation products or the excipients with the drugs was found. The linearity ranges were 50-600 ng/zone for levocetirizine and 100-1200 ng/zone for montelukast. The recovery was 99.3 % for levocetirizine and 99.9 % for montelukast.