Scholars Research Library 2(1), 489-494 (2010). HPTLC of montelukast sodium and levocetirizine dihydrochloride on silica gel with toluene - chloroform - methanol - glacial acetic acid 6:20:10:1 in a twin trough chamber with chamber saturation for 25 min. The hRf value of levocetirizine was 64 and of montelukast 89. Densitometric evaluation at 302 nm. The method was linear in the range of 200-3200 ng/band for montelukast and 400-1200 ng/band for levocetirizine. The recovery was 99.9-100.0 %.

Asian Journal of Chemistry 22(8), 5951-5955 (2010). TLC on silica gel with cyclohexane - methanol - ethyl acetate - 25 % ammonia 10:3:6:1. The hRf value was 7 for atenolol and 69 for nifedipine. Densitometric evaluation at 230 nm. The linearity was in the range of 3-21 µg/band for atenolol and 1.2-8.4 µg/band for nefidipine. The recovery was 100.7 % for both drugs. The method was found suitable for analysis of the combined dosage form of atenolol and nefidipine without interference of excipients.

J. Pharma. Sci. & Res. 2(8), 477-483 (2010). TLC on silica gel with ethyl acetate - glacial acetic acid - methanol - water 10:5:3:2. The hRf value was 51 and 74 for amoxicillin and bromhexine, respectively. Densitometric evaluation at 260 nm (bromhexine) and at 320 nm (amoxicillin). The method was linear in the range of 200-1000 ng/band and 10-30 µg/band for bromhexine and amoxicillin, respectively. The recovery was between 98.1-101.5 %.

Analytical Methods 2, 275-281 (2010). HPTLC on silica gel with toluene - methanol 9:1. The hRf value was 75. Densitometric evaluation at 372 nm. The method was linear in the range of 100-600 ng/band. The recovery was 99.2-100.4 %. The method was suitable for microemulsion based formulations without any interference from excipients.

J. Chromatogr. A 1218 (19), 2732-2736 (2011). A review on the sustainability and robust advantages of TLC and the parameters which are critical to the successful performance of product quality assessments in resource limited areas including field applications. The training required for successful performance of HPTLC assessments is much lower than that of other technologies with comparable reproducibility such as HPLC, because of the robustness and ease of use for HPTLC. Presentation of some of the successful applications of planar chromatography in resource limited countries. In practice in finished pharmaceutical products there are generally few active ingredients which are assessed making the HPTLC adequate for these analyses.

62nd Indian Pharmaceutical Congress Abstract No. F-335 (2010). TLC of ampicillin and dicloxacillin on silica gel with n-butanol – water – formic acid 63:6:4. Quantitative determination by absorbance measurement at 220 nm. The hRf values of ampicillin and dicloxacillin were 85 and 69 respectively. The linearity was in the range of 1-6 µg/zone for both ampicillin and dicloxacillin. The recovery for ampicillin was 98.5-101.9 % and that for dicloxacillin was 98.3-101.3 %.

62nd Indian Pharmaceutical Congress Abstract No. F-244 (2010). TLC of fluvoxamine maleate on silica gel with benzene – methanol 5:4. The hRf value was 52. Quantitative determination by absorbance measurement at 256 nm. The linearity was in the range of 500-3000 ng/band with r2=0.998. The drug was subjected to acidic, alkaline and oxidative, dry heat, UV and photolytic stress. Since the method could effectively separate the drug from its degradation products, it can be used for stability studies.

62nd Indian Pharmaceutical Congress Abstract No. F-261 (2010). TLC of montelukast sodium and levocetirizine dihydrochloride on silica gel with ethyl acetate – methanol – ammonia 10:2:1. Quantitative determination by absorbance measurement at 231 nm. Montelukast and levocetirizine were subjected to acid, base, peroxide, and photodegradation. In stability tests the drugs were susceptible to acid and basic hydrolysis, oxidation and photolytic degradation. The stressed samples were analyzed by the proposed method and no intereference of the degradation products or the excipients with the drugs was found. The linearity ranges were 50-600 ng/zone for levocetirizine and 100-1200 ng/zone for montelukast. The recovery was 99.3 % for levocetirizine and 99.9 % for montelukast.