J. Planar Chromatogr. 12, 356-360 (1999). TLC of salicylic acid, acetyl salicylic acid, ascorbic acid, paracetamol, caffeine, chlororacetanilide and dehydroascorbic acid on silica gel with i.a. n-hexane - chloroform - acetic acid 4:1:1. Detection under UV, except for dehydroascorbic acid which was identified by means of a color reaction with potassium iodoplatinate. Quantitation by densitometry.

J. Planar Chromatogr. 12, 356-360 (1999). TLC of acetylsalicylic acid, paracetamol, caffeine and salicylic acid on silica gel with n-hexane - chloroform - acetic acid 4:1:1 or ethanol - n-hexane - chloroform - acetic acid 12:12:8:1 for determination of ascorbic acid, and chloroform - acetone - toluene 12:5:2 for determination of paracetamol in the presence of ascorbic acid. Quantitation by densitometry at 280 nm. Rapid and accurate identification and quantitative determination.

J. Planar Chromatogr. 14, 42-46 (2001). RPTLC of 41 chalcones and chalcone analogs on silanized silica gel, after prewashing with methanol, with methanol - water and acetone - water mixtures after chamber saturation. Detection either visually, under UV 254 nm, and after spraying with iodine, or by densitometry at 254 nm. The RPTLC method was optimized and validated by analysis of three drugs, diazepam, progesterone, and PEG1 ethyl ester, with known experimental logP values. The logP values of 41 biologically active chalcones and their cyclic analogs, E-2-(X-benzylidene)-1-indanones, -tetralones and -benzosuberones have been determined by this optimized and validated RPTLC method.

Part VIII. Simultaneous determination of fluoxetine and (1RS)-3-methylamino-1-phenylpropan-1-ol, N-methyl-3-phenylprapan-1-amine, and C-1 as drug impurities. J. Planar Chromatogr. 15, 50-55 (2002). HPTLC of fluoxetine ((3RS)-N-methyl-3-phenyl-3-[4-(trifluoromethyl)phenoxy]propan-1-amine), (1RS)-3-methylamino-1-phenylpropan-1-ol, N-methyl-3-phenylpropan-1-amine, and (3RS)-N-methyl-3-phenyl-3-[(3-trifluoromethyl)phenoxy]-propan-1-amine on silica gel with a variety of mobile phases the best of which was chloroform - methanol - 25% NH3 90:9:1. Densitometry at 260 and 530 nm, after visualization with ninhydrin solution.

J. Planar Chromatogr. 15, 138-143 (2002). TLC of nicorandil (N-[(2-(nitroxy)ethyl]-3-pyridinecarboxamide), degradation products and impurities on RP-18 with acetonitrile - acetone - water 6:1:3. Quantitation by densitometry at 254 nm. The method is accurate (recovery = 100.20%), reproducible, rugged (intermediate precision, % RSD = 1.73; n = 18), and selective. The calibration plot for nicorandil was linear in the range 35 to 65 µg (70 to 130% of assay concentration). The method can be used for analysis of stability study samples and routine quality-control samples.

Indian J. Pharm. Sci., 64 (4), 362-366 (2002). HPTLC on silica gel with chloroform - methanol - NH3 90:10:1. Detection under UV 254 nm. The method was validated for linearity (200 - 600 ng), accuracy, precision and specificity. The method was found suitable for assay and contents uniformity. The proposed method is very fast and cost effective as 10 or more dosage forms units could be analyzed on a single plate simultaneously.

Proc. Intern. Symp. on Planar Separations Plan. Chrom. 369-375 (2003). TLC of betaxolol HCl, propanolol HCl, celiprolol HCl, oxprenolol, karvedilol, metoprolol tartrate, and atenolol on RP-18 with water - acetonitrile and water - dioxane in different concentrations. Visualization under UV 254 nm.

J. Planar Chromatogr. 16, 390-395 (2003). TLC of 5 series of anticonvulsant active N-substituted amides of a-arylalkylamine-g-hydroxybutyric acid (37 compounds) on RP-18 with mixtures of methanol, 0.1 M tris buffer pH 7.4, and acetic acid with chamber saturation. Visualization under UV 254 nm. Rapid, easy, and convenient method for determination of lipophilicity.