Abstract G-28, IPC (2005). HPTLC of rosuvastatin on silica gel with chloroform - methanol - toluene 3:1:1. Quantitative determination by absorbance measurement. The hRf value of rosuvastatin was 53, recovery rate was between 98-102 %, LOD was 8 ng/spot and LOQ 26 ng/spot.

J. AOAC Int. 88, 1525-1529 (2005). HPTLC of trandolapril and verapamil in 2-component mixtures and in their combination capsules on silica gel in horizontal chambers with ethyl acetate - ethanol - acetic acid 16:4:1. Quantitative determination by densitometric measurement at 215 nm. Detection and quantitation limits were found to be 1.25 and 3.75 µg/spot for TRA and 0.15 and 0.45 µg/spot for VER, respectively.

J. Planar Chromatogr. 18, 34 -38 (2005). Considering the latest technical and methodological developments, modern high-performance thin-layer chromatography, also known as planar chromatography, is a reliable and powerful analytical technique, in full compliance with current good-manufacturing practice (cGMP). With the proper equipment TLC is the method of choice when many samples must be analysed at low cost per sample. Advantages of HPTLC are shown in the analysis of botanicals: 1) Identification (separation of Stephania tetrandra root extracts with tetrandrine as standard on silica gel with toluene - ethyl acetate - methanol -ammonia 100:100:50:3; detection under UV at 254 and 366 nm, under white light after derivatization with iodine, and under UV at 366 nm after derivatization with anisaldehyde. 2) Semi-quantitative assessments in process control and stability tests (separation of fatty acids of Saw Palmetto products on RP-18 by two fold development with dichloromethane - acetic acid - acetone 2:4:5. 3) Quantitfication of marker compounds, like curcumin measured at 366 nm/>400 nm on silica gel with toluene - acetic acid 4:1. 4) Choice of stationary phase (separation of flavonoids on conventional TLC plates and on HPTLC plates with formic acid - water - ethyl methyl ketone - ethyl acetate 10:10:30:50 and detection with natural products reagent; switching to HPTLC reduced analysis time to a quarter and gave sharper bands). 5) Choice of mobile phase; 6) Derivatization and 7) Chromatogram evaluation.

J. Planar Chromatogr. 19, 216-222 (2006). TLC of ciprofloxacin monohydrate hydrochloride, enoxacin sesquihydrate, fleroxacin, norfloxacin, pefloxacin dihydrate mesylate, sparfloxacin, and ofloxacin on silica gel, cellulose and RP18 with numerous mobile phases. Best separations were achieved on silica gel with methanol - acetone - 1mol/L citric acid - triethylamine 28:2:2:5, on cellulose with dichloromethane - isopropanol - tetrahydrofuran - 25% ammonia 4:6:3:3, and on RP18 with methanol - 0.07 mol/L phosphate buffer (pH 6) - 10 mmol/L benzyldimethyltetradecylammonium chloride 6:3:1. Detection under UV light at 254 nm was more sensitive than spraying with Dragendorff reagent, Forrest’s reagent, 15 % FeCl3 in 2 % HCl, iodic reagent (5 g FeCl3 and 2 g I2 in 100 mL acetone - 20 % tartaric acid 1:1), 20 % phosphomolybdic acid in 10 % sulfuric acid, and Folin-Ciocalteu reagent.

J. Planar Chromatogr. 19, 204-207 (2006). HPTLC of florfenicol on silica gel in a twin-trough chamber with ethyl acetate - n-hexane 4:1. Quantitative determination by absorbance measurement at 223 nm. Linearity range of calibration curve was 20 -80 ng with a correlation coefficient r2 of 0.9987. Limit of detection was 2.55 mg / kg and limit of quantification was 8.50 mg / kg. Recovery was 101.7 % at 50 mg /kg, 85.2 % at 500 mg / kg and 81.9 % at 1500 mg / kg. Precision was evaluated based on intra-laboratory dispersion or repeatability. RSD for 50, 500, and 1500 mg / kg was 2.30, 2.72, and 3.57 % respectively.

Benth, identification by TLC fingerprint. Indian Drugs 42 (6), 392-395 (2005). Dried leaves of Pithecellobium Dulce. Benth were successively extracted with n-hexane, chloroform and alcohol. Each extract was evaluated for antimycobacterial activity. These extracts were subjected to TLC fingerprint profile for identification on silica gel with chloroform - methanol 9:1.

J. Planar Chromatogr. 19, 267-272 (2006). TLC of chelerythrine, chelidonine, and sanguinarine on silica gel with dichloromethane - methanol 97:3. Use of the mobile phase recommended by Ph. Eur. 5, propanol - water - formic acid 90:9:1, did not enable satisfactory separation of Chelidonium alkaloids. Development at 20 - 24 °C and 60 % relative humidity in a presaturated TLC chamber. After drying evaluation under UV light at 254 and 366 nm.

Phytochem. Anal. 17, 164-166 (2006). HPTLC of gymnemagenin on silica gel with chloroform - methanol 9:1. Quantitative determination by absorbance measurement at 290 nm. Linearity of the determination of gymnemagenin was observed in the range of 4 - 10 µg. The average percentage recovery from an extract was 99.1 %, the content of leaves was 1.61 % (dry weight).