J. AOAC Int. 91, 1387-1396 (2008). HPTLC on silica gel with chloroform - methanol 9:1 in the first direction for curcumin, demethoxycurcumin, bis(demethoxy)curcumin, and the synthetic dye metanil yellow, and with toluene - hexane - acetic acid 50:50:1 for sudan I and sudan IV in the second direction. Quantitative determination by absorbance measurement at 420 nm for curcumin and metanil yellow, at 491 nm for sudan I, and at 520 nm for sudan IV.

60th Indian Pharmaceutical Congress PA-202 (2008). HPTLC of 6-gingerol and 3-acetyl-11-keto-beta-boswellic acid on silica gel with n-hexane - ethyl actate 7:3 in a chamber saturated at ambient temperature. Quantitative determination by absorbance measurement at 254 nm. The hRf values were 48 and 58 for 3-acetyl-11-keto-beta-boswellic acid and 6-gingerol respectively. The recovery was 98.7-100.8 % for both compounds. The chromatographic conditions were suitable for routine analysis.

J. Liq. Chromatogr. Relat. Technol. 30, 2941-2951 (2007). TLC of 6-gingerol and 6-shogaol in commercial Ginger on silica gel with n-hexane - diethyl ether 2:3. Detection by spraying with anisaldehyde - sulfuric acid reagent. Evaluation under white light and quantitative determination by absorbance measurement at 577 nm.

Asian J. Chem. 19(6), 4286 - 4290 (2008). HPTLC of rofecoxib and tizanidine hydrochloride on silica gel with acetone - methanol 1:1. The method was linear in the range of 2200-3300 ng/spot and 180-260 ng/spot for rofecoxib and tizanidine respectively. The recovery was between 99.7 and 102.6 % for both compounds. The method was useful for the simultaneous estimation of the drug content in pure and tablet dosage form.

Ind. J. Pharm. Sci. 69 (5), 689 - 686 (2007). A simple, fast precise and accurate HPTLC method has been developed for the simultaneous estimation of lansoprazole and domperidone in tablet formulations. This method allows the determination of 100-500 ng/spot of lansoprazole and 100-500 ng/spot of domperidone. HPTLC on silica gel with n-butanol - acetic acid - water 36:12:1:2. Quantitative determination by absorbance measurement at 288 nm. The hRf value of lansoprazole was 78 and of domperidone 21. The limit of detection and quantification for lansoprazole was 10 ng/spot and 40 ng/spot, and for domperidone 30 ng/spot and 65 ng/spot, respectivey. The method was suitable for routine quality control.

obtained by use of different techniques. J. Planar Chromatogr. 22, 25-28 (2009). HPTLC of flavonoids (rosmarinic acid and luteoline) on silica gel with ethyl acetate - formic acid - water 136:5:6, ethyl acetate - methanol - water 77:13:10, ethyl acetate - diethyl ether 4:1, n-hexane - ethyl acetate - formic acid 60:40:3, chloroform - methanol - formic acid 882:60:47, and chloroform - acetone - formic acid 19:4:2. The mobile phase chosen for quantification was chloroform - ethyl acetate - formic acid 60:40:3. Detection by spraying with natural products reagent, followed by polyethylene glycol 400 reagent. Quantitative determination by densitometry at 328 nm (rosmarinic acid) and 349 nm (luteoline).

Anal. Chem. 79, 8789-8795 (2007). TLC of dyes, amines, extracts of drug tablets (erythoxine B, erioglaucine, fast green FCF, 2,2’-diaminodiethylamine, 3-quinolinamine, 2-acetylaniline; tablets containing DL-methylephedrin hydrochloride, caffeine, ethoxybenzamide, chlorpheniramine maleate, noscapine, acetaminophen) on RP-18 with 500 mM ammonium acetate - acetone 7:3. Separation of amines on silica gel with ethyl acetate - acetic acid - dichloromethane 98:1:1. The detection limit of TLC/ELDI/MS is 1 µM.

J. Chromatogr. A 1112 (1-2), 156-164 (2006). HPTLC of glucosamine in a dietary supplement containing dried extracts of the main plants traditionally used for rheumatic disorders, on silica gel with a saturated mixture of 2-propanol - ethyl acetate - ammonia (8 %) 1:1:1. Detection by dipping into a modified anisaldehyde reagent and heating at 120 °C for 30 min in a drying oven. Quantitative determination by absorbance measurement at 415 nm. Validation of the method by applying the novel validation protocol proposed by a commission of the Société Française des Sciences et Techniques Pharmaceutiques. Relative standard deviations for repeatability and intermediate precision were between 4.9 and 8.6 %, accuracy was good, the two-sided 95 % beta-expectation tolerance interval was within the acceptance limits of 85 and 115 % on the whole analytical range (800 - 1200 ng of glucosamine).