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.

Anal. Chim. Acta, 572 (2), 237-242 (2006). Presentation of a stability-indicating method for simultaneous determination of the steroidal hormones levonorgestrel and ethinyloestradiol both in bulk drug and in low-dosage oral contraceptives by HPTLC on silica gel with hexane - chloroform - methanol 4:12:1. The hRf value of levonorgestrel was 65 and of ethinyloestradiol 43. The compounds were well separated from their degradation products. Quantitative determination by absorbance measurement at 225 nm. Linearity of levonorgestrel and ethinyloestradiol was 200–800 and 40–160 ng/spot, respectively.

Phytochem. Anal. 20, 154-158 (2009). TLC of the purgative constituents of rhubarb (sennoside A and sennoside B) on silica gel with 1-propanol - ethyl acetate - water - acetic acid 40:40:30:1. After drying detection by spraying with 10 % sulfuric acid and heating. For the eastern blotting assay the developed TLC plate was dried and sprayed with isopropanol - methanol - water 1:4:16. Transfer by using a PVDF membrane sheet for further treatment.

Chinese J. Modern Appl. Pharm. 25 (1), 66-69 (2008). TLC of Qufu Zhuanggu capsule extracts on silica gel with 1) n-hexane - ethyl acetate 4:1; 2) benzene - ethyl acetate 9:1; 3) chloroform - methanol 19:1; 4) cyclohexane - ethyl acetate 5:2; 5) n-hexane - acetone 3:1. Detection 1) under UV 365 nm; 2) by spraying with 10 % sulfuric acid in ethanol and heating at 105 ºC until the spot were visualized; 3) by treatment with ammonia vapors for 10 min; 4) by spraying with 20 % HClO4 in ethanol. Identification by comparison of the chromatograms with those of the standard psoralen.

Abstract No. 9192, IHCB (2009). HPTLC of betulinic acid in hydro alcoholic extracts of Nelumbo nucifera rhizome and seed, on silica gel with chloroform - methanol - formic acid 49:1:1. Detection by spraying with anisaldehyde reagent. Quantitative determination by absorbance measurement at 420 nm. The method was linear in the range of 2-10 ng/spot, recovery was 98.1-98.4 %.

J. Chromatogr. A 1216 (42), 7102-7107 (2009). HPTLC of co-trimoxazole tablets (combination of sulfamethoxazole and trimethoprim) on silica gel with toluene – ethyl acetate – methanol 100:57:43. Detection under UV 254 nm. The hRf values were 30 and 61 for trimethoprime and sulfamethoxazole, respectively. Quantification by densitometry at UV 254 nm. Cochran's criterion test indicated homoscedasticity of variances for the calibration data. The F-tests for lack-of-fit indicated that straight lines were adequate to describe the relationship between spot areas and concentrations for each compound. Repeatability and precision (%RSD) was 1.0 and 0.8 % for sulfamethoxazole as well as 1.3 % and 1.6 % for trimethoprim, respectively. Recovery was 99.0 % and 99.7 % for sulfamethoxazole and trimethoprim, respectively.

60th Indian Pharmaceutical Congress PA-230 (2008). HPTLC of amlodipine besylate (AB) and telmisartan (TMS) on silica gel with ethyl acetate - 1,4-dioxane - methanol - 25 % ammonia 30:3:6:3. The hRf value was 16 for TMS and 33 for AB. Quantitative determination by absorbance measurement at 323 nm. The method was linear in the range of 100-500 µg/mL (TMS) and 200-1000 µg/mL (AB), average recovery was 100.2-100.4 %.