J. Planar Chromatogr. 23, 84-86 (2010). TLC of 18 drugs (6 antibiotics [benzyl-penicillin procaine, benzyl-penicillin potassium, penicillic acid, tetracycline hydrochloride, oxytetracyline hydrochloride, chlortetracycline hydrochloride], 2 analgesics [aminophenazone, salicylamide], 2 anaesthetics [phenazone, procaine hydrochloride], and one each of anti-rheumatic [penicillamine], anti-inflammatory [metamizole sodium], antitussive [codeine phosphate], broncholytic [aminophylline], spasmolytic [papaverine hydrochloride], hypnotic [phenobarbital], sympathomimetic [ephedrine hydrochloride] and vitamin [ascorbic acid] drugs) on silica gel with butanol - anhydrous acetic acid - water 3:1:1. Detection by spraying with 10 mL each of a solution of (A) 0.25 g titanum dioxide in 0.1 mol/L potassium permanganate, (B) 0.25 g titanium dioxide in 1.0 mol/L potassium iodide, (C) 0.25 g titanium dioxide in 1.0 mol/L potassium bromide, which was the best (most sensitive) one, and (D) 0.25 g titanium dioxide in 1.0 mol/L potassium chloride. After spraying with reagents C and D, plates were illuminated for 10 min, sprayed with 0.1 mol/L silver nitrate solution and illuminated again for 3 min. In all experiments the TLC plates were illuminated by use of UV lamps with the radiation at 366 nm. LODs for most of the drugs studied were in the range 0.2-0.5 µg/spot.

J. Planar Chromatogr. 23, 212-218 (2010). TLC of bupropion on silica gel with ethanol - chloroform - glacial acetic acid 30:10:1. The hRf value was 56. Quantitative determination by densitometry at 254 nm. Linearity was in the range 200-1000 ng/band (via peak area). The limits of detection and quantitation were 11 and 35 ng per band, respectively. The intra-day repeatability of the method was around 1-2 % RSD. Recovery was between 102.1 and 104.6 % and between 97.2 and 102.2 % for quality-control standards and for bupropion hydrochloride, respectively.

62nd Indian Pharmaceutical Congress Abstract No. F-382 (2010). The partition coefficient (logP) of a drug in benzene – water is an important parameter to determine the absorbance of the drug in body, thus influencing its therapeutic response. A NP-TLC method for the determination and calculation of log P values is proposed. By this method differential values like Rfb/w, LogRfb/logRfw were calculated, which were very close to values reported in literature. LogP values of different drugs were 0.46 for paracetamol, 0.22 for atenolol, 5.11 for telmisertan, and 0.9 for nimesulide.

J. Planar Chromatogr. 24, 154-159 (2011). TLC of avobenzone (methoxydibenzoylmethane), octocrylene, Uvinul T 150 (ethyl hexyl triazone, ET), and ethylparaben on silica gel with cyclohexane - diethyl ether 1:1 (method A), or with cyclohexane - piperidine 15:1 (method B), in a chamber lined with filter paper and saturated for 20 min. Quantitative determination by densitometry at 380 nm for avobenzene and at 300 nm for octocrylene. LOD and LOQ were 170 and 510 ng/zone for avobenzone (method A) and 180 and 537 ng/zone for octocrylene (method B), respectively. The linearity range was 200-1800 ng/zone for avobenzone and octocrylene.

J. Liq. Chromatogr. Relat. Technol. 34, 1664-1675 (2011). HPTLC of pramipexole in pharmaceutical formulations on silica gel with ethyl acetate - toluene - methanol 16:3:1 + 1 drop ammonia. Quantitative determination by absorbance measurement at 263 nm. The hRf value of pramipexole was 32. Precision was below 2 %. Linearity was 200-2000 ng/zone. LOD and LOQ were found to be 30 and 200 ng/zone. The intermediate/inter-day/intra-day precision (n = 6) was 0.4 %. Recovery (by standard addition) was in the range of 98.5-99.1 %.

J. Liq. Chromatogr. Relat. Technol. 35, 524-532 (2012). HPTLC of atorvastatin calcium (1), ezetimibe (2), and fenofibrate (3) in tablet on silica gel with toluene – chloroform – methanol 23:15:7 + 1 drop glacial acetic acid. Quantitative determination by absorbance measurement at 253 nm. The hRf values of active agents (1) - (3) were 20, 33 and 80, respectively. Linearity was 200-800 ng/zone for (1) and (2) and 4-16 µg/zone for (3). The intermediate/inter-day/intra-day precision was below 1.1 % for (1), 1.3 % for (2) and 1.5 % for (3) (n=6). The limits of detection and quantification were 19 and 59 ng/zone for (1), 23 and 68 ng/zone for (2), and 1449 and 4390 ng/zone for (3), respectively. Recovery (by standard addition) was between 99.1 and 99.8 % for compounds (1) to (3).

J. Planar Chromatogr. 26, 86-92 (2013). HPTLC of carteolol on silica gel with chloroform - methanol 5:1. Quantitative determination by absorbance measurement at 254 nm. The hRf of carteolol was 31. Linearity was in the range of 200-1200 ng/zone. LOD and LOQ were 34 ng/zone and 104 ng/zone, respectively. Intermediate precision was below 2 %. The method could effectively separate the drug from its degradation products.

J. Planar Chromatogr. 25, 133-137 (2012). HPTLC of thiocolchicoside (1) and aceclofenac (2) in combined dosage form on silica gel with methanol - chloroform - water 48:1:1. Quantitative determination by absorbance measurement at 254 nm. The hRf values of (1) and (2) were found to be 70 and 83, respectively. Linearity was in the range of 30-180 ng/band for (1) and 750-4500 ng/band for (2). Recovery was in the range of 98.7-101.2 % for both.