by HPTLC. Abstract No. 9191, IHCB (2009). HPTLC of (-)hydroxy citric acid (the main constituent of Garcinia gummigutta fruits) on silica gel with n-propanol - water - glacial acetic acid 50:50:1. Quantitative determination by absorbance measurement at 210 nm. The hRf value was 46. The method was linear in the range of 100-1000 ng/spot, recovery was 99.8-100.9 %.

J. AOAC Int. 92, 745-756 (2009). HPTLC of 25 dyes (brilliant black BN, tartrazine, ponceau 6 R, resorcin yellow, fast yellow AB, orcein, allura red, green S, amaranth, quinoline yellow, acid blue, erythrosine, sunset yellow FCF, indigo carmine, ponceau 4R, azorubine, brilliant blue FCF, carmine, scarlet GN, copper chlorophyll, enocyanine, chlorophyllin trisodium copper salt, curcumin, riboflavin-5-phosphate, riboflavin) on silica gel in a horizontal developing chamber with ethyl acetate - methanol - water - acetic acid 65:23:11:1 for 40 samples in 12 min. Relative humidity was 21 +/- 3 % at a temperature of 20 +/- 3 °C. Alternatively, a twin trough chamber or automatic developing chamber can be used. Quantitative determination by absorbance measurement at 11 different wavelengths. Repeatabilities (%RSD, n = 4) near the limit of quantification showed precisions of mostly <2.7 %, ranging between 0.2 and 5.2 %. Correlation coefficients (R >0.9987) and RSD values (<4.2 %) of the calibration curves were highly satisfactory using classical quantification. However, digital evaluation of the plate image was also used for quantification, which resulted in RSD values of the calibration curves of mostly <3.0%, except for two <6.0%. The method was applied for the analysis of some energy drinks and bakery ink formulations, directly applied after dilution. By recording of absorbance spectra in the visible range, the identities of the dyes found in the samples were ascertained by comparison with the respective standard bands (correlation coefficients >0.9996). If necessary for confirmation, online mass spectra were recorded within a minute.

The Pharma Review 7(39), 151-153 (2009). HPTLC of atorvastatin calcium and fenofibrate on silica gel (pre-washed with methanol) with chloroform - methanol 4:1 over 20 mm with chamber saturation. The hRf value of atorvastatin calcium was 29 and of fenofibrate 77. The method was linear in the range of 200-1000 ng/band for atorvastatin calcium and 320-1600 ng/band for fenofibrate.

60th Indian Pharmaceutical Congress PA-220 (2008). HPTLC of domperidone and esomeprazole on silica gel with chloroform - methanol 9:1 with chamber saturation for 30 min. The hRf value was 25 for domperidone and 46 for esomeprazole. Quantitative determination by absorbance measurement at 295 nm. The method was linear in the range of 60-300 ng/spot for domperidone and 80-400 ng/spot for esomeprazole.

Abstract No. F-378, 61st IPC (2009). HPTLC of telmisartan and hydrochlorothiazide on silica gel with chloroform - toluene - methanol 2:5:5. The hRf value was 53 and 75 for telmisartan and hydrochlorothiazide respectively. Quantitative determination by absorbance measurement at 271 nm. The method was linear in the range of 240-640 ng/band for telmisartan and 200-700 ng/band for hydrochlorothiazide.

Abstract No. 9286, IHCB (2009). HPTLC of dially disulfide in garlic oil macerate on silica gel with n-hexane - isopropyl alcohol - formic acid 196:4:3. Quantitative determination by absorbance measurement at 210 nm. The method was linear in the range of 16-48 µg/spot.

Abstract No. F-311, 61st IPC (2009). HPTLC of levocetirizine dihydrochloride and montelukast sodium on silica gel with chloroform - methanol 93:7. The hRf value was 21 and 65 for levocetrizine and montelukast, respectively. Quantitative determination by absorbance measurement at 345 nm. The method was linear in the range of 100-350 ng/band for levocetrizine and 600-1100 ng/band for montelukast.

J. Planar Chromatogr. 22, 245-348 (2009). HPTLC of doxofylline (7-(1,3-dioxalan-2-ylmethyl)theophylline) in bulk drug and in formulations on silica gel, prewashed with methanol, with toluene - methanol 4:1 in a twin trough chamber saturated for 20 min. Quantitative determination by absorbance measurement at 275 nm.