J. Planar Chromatogr. 17, 51-53 (2004). TLC of gallic acid, salicylic acid and tannic acid on silica gel with chloroform - ethyl acetate - formic acid 5:4:1. Detection with the iron(III) - 2,2’-dipyridyl system (iron ammonium sulfate and sulfuric acid in water and 2,2’-dipyridyl in hydrochloric acid). Quantitative determination at 280 nm. Limit of detection 0.1 µg per spot.

Chinese J. Trad. Patent Med. (Zhongchengyao) 26 (5), 371-373 (2004). TLC of Xiaozhi tablet extracts on silica gel with 1) ethyl acetate - formic acid - water 5:2:1; 2) benzene - acetone - ethyl acetate - ammonia 4:6:8:1; 3) chloroform - methanol - ammonia 40:10:1. Detection 1) under UV light; 2) by spraying with 5 % solution of potassium iodobismuthate. Identification by fingerprint techniques. Quantification of matrine by HPLC with method validation.

Chinese J. Trad. Patent Med. (Zhongchengyao) 26 (2), 164-165 (2004). TLC of Fukang Xiaozhong pills on silica gel with the lower phase of chloroform - ethyl acetate - methanol - water 6:8:3:2. Detection by spraying with 5% potassium iodobismuthate solution. Identification by comparison with the standard. Quantification by densitometry at 502 nm. Validation of the method by investigation of its linearity range (0.41-2.05 µg/spot, r = 0.9999); precision (RSD=1.66% n=5 within plate and 1.88% n=5 plate-to-plate); reproducibility and standard addition recovery (98.9% RSD=1.9% n=5).

J. Planar Chromatogr. 17, 164-168 (2004). HPTLC of flupirtine maleate on silica gel with ethyl acetate - methanol - 25 % ammonia 17:2:1 in a saturated developing chamber. Then the developed plate must be dipped for 2 s in 1:3 paraffin - hexane. Dipping increases the fluorescence tenfold and preserves the fluorescence stability for hours. Presentation of a new formula for transforming fluorescence measurements in accordance with Kubelka-Munk theory. The fluorescence signals, the absorption signals, and data from a selected reference are combined in one expression. Only diode-array techniques can measure all the required data simultaneously. The fluorescence calibration curve was linear over the range 300 to 5000 ng per spot.

foliage. J. Planar Chromatogr. 17, 218-223 (2004). TLC of gamma-coniceine and coniin on silica gel with chloroform - ethanol 13:7. Detection and quantification by spraying with Dragendorff’s spray reagent and visual comparison of the intensity of the colour of the sample spots with that of the spots of the corresponding standards. Detection limits wered 1.7 and 0.7 µg per spot for coniine and gamma-coniceine, respectively.

IPC 56th 2004, Abstract No. GP-5. Simultaneous HPTLC determination of amlodipine and atenolol on silica gel with ethyl acetate - methanol - ammonia 60:40:3. Quantitative determination by scanning at 254 nm. The method was found linear in the range of 0.5 – 5.0 mg/mL amlodipine and 5.0 mg – 50 mg/mL atenolol. Recovery was 98.11 – 101.5 % for both of the compounds. The method was validated for accuracy, precision, linearity, specificity, LOD, and LOQ.

56th IPC 2004, Abstract No. GP-48. HPTLC of rabeprazole sodium in tablet dosage form on silica gel with ethyl acetate - methanol 9:1. Optimization of experimental parameters such as bandwidth, chamber saturation time, solvent front migration, and mobile phase composition. Quantitative determination by scanning at 260 nm. The Rf value was 0.59. The method was linear with a correlation coefficient of 0.99, recovery was 98.81 %.

Chinese J. Trad. Pat. Med. (Zhongchengyao) 26 (9), App.14-16 (2004). TLC on silica gel with 1) toluene - ethyl acetate - formic acid 25:20:4; 2) ethyl acetate - methanol - water 100:17:13. Detection 1) by spraying with diazotized para-nitroaniline solution; 2) by spraying with 5 % AlCl3 in ethanol and under UV 365 nm. Identification by fingerprint technique. Quantification of hesperidin by HPLC.