Research J. Pharm. and Tech. 3(2), 559-561 (2010). TLC on silica gel with toluene - acetonitrile - formic acid 50:50:3 with chamber saturation for 30 min. The hRf value was 27 for perindopril and 55 for losartan. Densitometric evaluation at 212 nm. The method was linear in the range of 5-30 µg/band and 1-10 µg/band for losartan and perindopril respectively. The average recovery was 98.2-99.9 %.

Journal of Pharmaceutical Research 9(2), 60-62 (2010). TLC on silica gel with chloroform - ethyl acetate - methanol - ammonia 20:20:10:1 with chamber saturation for 30 min. Densitometric evaluation at 232 nm. The method was linear in the range of 100-800 ng/band for amlodipine, 400-2400 ng/band for hydrochlorothiazide and 1000-8000 ng/band for amlodipine. The average recovery was 99.1-100.4 % for all three compounds. The method was suitable for stability studies (stress conditions: acid, base, thermal, UV).

62nd Indian Pharmaceutical Congress Abstract No. F-259 (2010). Health drinks usually contain several phytopharmaceuticals with immunomodulatory and antioxidant activities. TLC of gallic acid on silica gel with toluene – ethyl acetate – methanol – formic acid 15:15:1:4. The gallic acid content was established and the identity of the gallic acid zone in sample and standard was confirmed by UV spectra comparison.

62nd Indian Pharmaceutical Congress Abstract No. F-384 (2010). TLC of isotretinoin on silica gel with toluene – ethyl acetate 4:1. The hRf value was 54. Quantitative determination by absorbance measurement at 345 nm. The method was linear in the range of 20-100 ng/band. The sample was analysed by RP-HPLC and the result was comparable with the TLC method.

by HPTLC. 62nd Indian Pharmaceutical Congress Abstract No. F-248 (2010). TLC of harmine in stem bark of Symplocos racemosa Roxb. on silica gel with toluene – ethyl acetate – methanol 3:1:1. Quantitative determination by absorbance measurement at 324 nm. The linearity of the method was in the range of 100-500 ng/band.

62nd Indian Pharmaceutical Congress Abstract No. F-343 (2010). TLC of hydrochlorothiazide (HCTZ) and irbesartan (IRBE) on silica gel with toluene – acetic acid – methanol 70:2:50. Quantitative determination by absorbance measurement at 264 nm. The hRf values were 15 for HCTZ and 45 for IRBE. The linearity was in the range of 90-540 ng/band and 180-900 ng/band with r2= 0.9989 for HCTZ and IRBE. The recovery of HCTZ was 95.3-97.7 % and of IRBE 95.2-98.7 %.

J. of Chromatogr. Sci. 49, 129-135 (2011). TLC on silica gel with ethyl acetate – chloroform – formic acid – triethyl amine 70:30:1:1. Detection and quantification by densitometry. Good correlation between the integrated peak area of the studied drugs and their corresponding concentrations was found in different ranges.

J. Sep. Sci. 34, 286-291 (2011). HPTLC of 1beta,3alpha,8beta-trihydroxy-pimara-15-ene (1), 6alpha,11,12,16-tertahydroxy-7-oxo-abieta-8,11,13-triene (2) and 2alpha,19-dihydroxy-primara-7,15-diene (3) in the root bark of Premna integrifolia on silica gel with hexane – acetone – ethyl acetate 3:1:1. Detection by dipping into vanillin-sulfuric acid reagent (2 g vanillin in 190 mL ethanol with 10 mL sulfuric acid) followed by air drying and heating for 3 min at 110 °C. Quantitative determination by absorbance measurement at 475 nm. The hRf values of (1), (2) and (3) were 58, 44, and 32, respectively and selectivity regarding matrix was given. Linearity was between 1-10 µg/spot for (1), (2) and (3), respectively. The limits of detection were found to be 230, 106 and 336 ng/band for compounds (1), (2) and (3), respectively, whereas the limits of quantification were 769, 354 and 1122 ng/band, respectively. Inter- and intraday precisions were 0.9-1.3 % and 1.1-1.2 %, respectively. The average recoveries for compounds (1) to (3) were found to be 100.6, 103.9 and 97.6 %, respectively, within the acceptable %RSD.