Asian Journal of Chemistry 22(4), 3283-3291 (2010). TLC of vitamins B1, B6, and B12 in formulations on bentonite-coated TLC plates (0.3 mm) with iso-butylalcohol - methanol - chloroform - acetic acid - ammonia 75:10:35:4:5. The hRf value of vitamin B1 was 26, of B6 37 and of B12 68. The method was linear in the range of 500-4000 ng/band for all three vitamins. Densitometric quantification at 275 nm for B1, B6, and B12 and at 525 nm for B12.

Research Journal Pharm and Tech. 2(4),746-748 (2009). A validated HPTLC method is reported for simultaneous estimation of nebivolol hydrochloride and valsartan in combined dosage form. HPTLC on silica gel with ethyl acetate - methanol - 25 % ammonia. The hRf value of valsartan was 27 and of nebivolol 75.The method was linear in the range of 800-2400 ng/band for nebivolol and 200-1000 ng/band for valsartan. Densitometric quantification at 280 nm. The method was found suitable for routine quality control of the combined dosage form.

Journal of Natural Remedies 10(2), 170-174 (2010). The powdered plant material was defatted, extracted with methanol, concentrated and successively extracted with ethyl acetate and n-butanol. The resulting fractions were concentrated and subjected to chromatographic fingerprint analysis of the phytoconstituents, i.e. alkaloids, saponins, tannins, flavonoids, anthraquinones and sterols. TLC on silica gel with n-butanol - acetic acid - water 4:1:5 for the ethyl acetate fraction and with chloroform - methanol 9:1 for the n-butanol fraction. Densitometric evaluation at 254 nm and 366 nm for the n-butanol fraction and at 290 nm for the ethyl acetate fraction. Derivatization with vanillin-sulfuric acid reagent for the n-butanol fraction and with AlCl3 reagent for the ethyl acetate-fraction, evaluation at 600 nm. The n-butanol fraction contained sterols and saponins, the ethyl acetate fraction flavonoids.

J. Chromatogr. Sci. 48, 68-75 (2010). TLC of cefaclor, cefadroxil, cefalexin and cefradine on silica gel with ethyl acetate - methanol - water in different ratios. The studied drugs had hRf values between 40 and 60. Detection of blue to violet colored zones after spraying with ninhydrin reagent. Quantification by densitometry. Linearity was in the range of 2-10 µg/zone with correlation coefficients ranging from 0.9990 to 0.9996 and determination coefficients from 0.9986 to 0.9992 for all studied drugs. The limits of detection and quantification for all studied drugs were between 90 to 230 ng/zone and 270 to 840 ng/zone, respectively.

62nd Indian Pharmaceutical Congress Abstract No. F-324 (2010). TLC of curcumin, piperine and quercetin in ayurvedic extract on silica gel with chloroform – toluene – ethyl acetate – methanol 4:4:1:1. The results obtained by the chromatographic method were comparable with a UV-VIS photometric method. All three compounds did not show any mutual interference.

62nd Indian Pharmaceutical Congress Abstract No. F-246 (2010). TLC of atorvastatin calcium, ezetimibe and fenofibrate on silica gel with toluene – methanol – chloroform 6:3:4. Quantitative determination by absorbance measurement at 280 nm. The method was found to be linear in the range of 100-600 ng/band for atorvastatin calcium and ezetimibe and 50-300 ng/band for fenofibrate.

J. Pharm. Biomed. Anal. 54, 497-502 (2011). HPTLC of three bioactive steroidal glycoalkaloid markers, solasonine (SN), solamargine (SM) and khasianine (KN) in the plant Solanum xanthocarpum. The extraction effciency of targeted SGAs from plant matrix using methanol and acidified methanol were studied using percolation, ultrasonication and microwave techniques. HPTLC on silica gel with chloroform – methanol – water. The hRf values were 31, 37, and 52 for SN, SM, and KN, respectively. Quantitative determination by absorbance measurement at 520 nm after derivatization using Dragendorffs reagent. The linearity range was 2-10 µg/band for SN and SM and 6-30 µg/band for KN. Method specificity was confirmed using hRf values, correlation of UV spectra and comparison of ionization mass spectra (ESI-MS) of marker compounds in the sample track.

62nd Indian Pharmaceutical Congress Abstract No. F-236 (2010). TLC of rupatadine formulation on silica gel with acetonitrile – water – formic acid 50:50:3. The hRf value was 67. Quantitative determination by absorbance measurement at 263 nm. The method was linear in the range of 1-20 µg/band.