CBS 93, 10-12 (2004). HPTLC of progesterone on silica gel prewashed by development in AMD2 first with chloroform - methanol 1:1 and then with the mobile phase, followed by drying at 80 °C for 15 min. Development in AMD2 with toluene - 2-propanol 10:1 without preconditioning over 60 mm. Quantitative determination by absorbance measurement at 252 nm followed by spectra recording from 200 to 360 nm. The linear working range is 25.7-154.5 ng/zone. Repeatability (standard deviation calculated from the amounts of seven simulated progesterone samples determined on the same plate at three concentration levels in the lower, middle and upper range) is 0.26-1.29 %. Recovery is 99.88-100.97 %. Reproducibility was performed with recycled HPTLC plates.

Indian Drugs 41 (3), 160-164 (2004). Combinations of ofloxacin and tinidazole (1:3) are available as tablet dosage forms. Stability indicating HPTLC of ofloxacin and tinidazole on silica gel with dioxan - ethyl acetate - toluene - acetic acid - water 5.5:5:3.2:2:2 . Quantification by absorbance measurement at 307 nm. The Rf value of ofloxacin and tinidazole was found to be 0.12 and 0.85 respectively. Recovery was 99.85 % and 99.45 % for ofloxacin and tinidazole respectively. The proposed method was quantitatively evaluated in terms of calibration of concentration range, stability, and accuracy. It can be adopted for routine analysis of the formulation.

Indian J. Pharm. Sci. 66 (3), 278-282 (2004). HPTLC on silica gel with chloroform - acetonitrile - toluene - acetate buffer (pH 6.0) 50:40:10:3. Quantitative determination by absorbance measurement at 266 nm. The method was validated in terms of linearity, accuracy, precision, and specificity. The limit of detection and the limit of quantification were found to be 50 ng/spot and 100 ng/spot respectively. A simple, precise, accurate and rapid HPTLC method has been developed and validated for the simultaneous determination of cefuroxime axetil and probenecid in combined dosage form.

Chinese J. Trad. Patent Med. (Zhongchengyao) 26 (8), Appendix 16-18 (2004). Study of the identification of Shenbao capsules by TLC, in addition to microscopy and chemical methods. TLC of Shenbao capsule extracts on silica gel with 1) the lower phase of chloroform - ethyl acetate - methanol - water 15:40:22:10; 2) toluene - methanol 4:1. Detection 1) by spraying with 10 % H2SO4 in ethanol followed by heating at 105 ºC; 2) under UV light. Identification by fingerprint technique. Combination of the procedure with microscopy and chemical methods allows identification of all drug ingredients.

IPC 56th 2004, Abstract No. G-20. Simultaneous HPTLC determination of loratadine and ambroxol in combined dosage form on silica gel with n-hexane - dichloromethane - triethanolamine 11:8:1.The Rf value of loratadine and ambroxal was found to be 0.40 and 0.16 respectively. Quantitative evaluation by scanning at 254 nm.The method was linear in the range of 0.2 -1 mg/spot for loratadine and 1.2 - 6 mg/spot for ambroxol with recovery of 98.2 - 98.5 %. The method was validated for accuracy, precision, linearity, specificity, LOD, and LOQ.

Densitometric determination of mexiletine hydrochloride in capsules. J. Planar Chromatogr. 17, 213-217 (2004). TLC of disopyramide, flecainide, mexiletine, tocainide, and verapamil on aluminium oxide and silica gel in horizontal chambers. The best mobile phase for separation on the alumina plates was tetrahydrofuran - hexane - 25 % ammonia 25:24:1 and on silica chloroform - tetrahydrofuran - ethanol - 25 % ammonia 81:19:20:1. Detection under UV light at 210 nm and by use of different reagents. Quantification of mexiletine hydrochloride in capsules was performed densitometrically at 254 nm.Correlation coefficient in the concentration range 20 - 45 µg per band was 0.9974, with RSD of 5.23 %.

Chinese J. Trad. Pat. Med. (Zhongchengyao) 26 (9), app.19-20 (2004). HPTLC on silica gel with petroleum ether (30 - 60 ºC) - formic acetate - formic acid 15:5:1, at 11 ºC and humidity of 40 %. Detection by exposing to ammonia vapors. Identification by fingerprint technique and comparison with the standards.

J. AOAC Int. 88, 1555-1561 (2005). HPTLC of chloramphenicol on silica gel in a horizontal developing chamber (36 applications per plate) using n-hexane -ethyl acetate 7:13. Quantitative determination by absorbance measurement at 280 nm. Mean recovery was 95.8 %, and the coefficient of variation was 5.8 %. The detection limit was 3 ng, and the quantitation limit 10 ng.