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Two sensitive and selective methods were developed and validated for simultaneous determination of pramocaine HCl and hydrocortisone acetate in pharmaceutical dosage form. The first method is a spectrodensitometric method where pramocaine HCl and hydrocortisone acetate were separated using toluene:methanol:chloroform: 10% NH3[(5:3:6:0.1, by volume) as the developing system followed by densitometric measurement at 290 nm] and 250 nm for pramocaine HCl and Hydrocortisone acetate, respectively. The second method is a high performance liquid chromatographic method for separation and determination of both drugs using reversed phase C18column and mobile phase consisting of distilled water:acetonitrile:triethylamine (530:470:0.1, by volume); pH was adjusted to 3 by o-phosphoric acid. The proposed methods were successfully applied for the analysis of pramocaine HCl and hydrocortisone acetate in laboratory prepared mixtures and in pharmaceutical dosage form and the results obtained were assessed by applying the standard addition technique. Statistical comparison between the results obtained by applying the proposed methods and official method for the cited drugs was done and no significant difference was found at p = 0.05. [ABSTRACT FROM AUTHOR]

Adsorption thin layer chromatography (NP-TLC) with densitometry has been established for the identification and the quantification of acetylsalicylic acid, caffeine, and ethoxybenzamide in combined tablets. UV densitometry was performed in absorbance mode at 200 nm, 275 nm, and 300 nm for acetylsalicylic acid, caffeine, and o-ethoxybenzamide, respectively. The presented method was validated by specificity, range, linearity, accuracy, precision, detection limit, quantitative limit, and robustness. It could be said that the NP-TLC-densitometric method is suitable for the routine analysis of acetylsalicylic acid, caffeine, and ethoxybenzamide in combined tablets in quantity control laboratories. [ABSTRACT FROM AUTHOR]

Adsorption thin layer chromatography (NP-TLC) with densitometry has been established for the identification and the quantification of acetylsalicylic acid in tablets. UV densitometry was performed in absorbance mode at 200 nm. The presented method was validated by specificity, range, linearity, accuracy, precision, detection limit, quantitative limit, and robustness. The TLC-densitometric method was also compared with a pharmacopeial UV-spectrophotometric method for the assay of acetylsalicylic acid, and the results confirmed statistically that the NP-TLC-densitometric method can be used as a substitute method. It could be said that the NP-TLC-densitometric method is suitable for the routine analysis of acetylsalicylic acid in quantity control laboratories. [ABSTRACT FROM AUTHOR]

NP-TLC and RP-TLC techniques with the densitometry were compared to the determination of tocopherol acetate in oral fluid Vitaminum E. It was stated, that tocopherol acetate was better separated from tocopherol using NP-TLC technique than RP-TLC technique. Therefore, NP-TLC with densitometry has been used for the identification and the quantitative determination of tocopherol acetate in pharmaceutical preparation. The NP-TLC method with densitometry was validated. The accuracy of the method was evaluated by measurement of recovery. According to the results of the experiments performed using the NP-TLC-densitometric method, it was determined that the procedure used in this study is reliable with specificity, accuracy, precision, and robustness. It could be said that the NP-TLC-densitometric method is suitable for the routine analysis of tocopherol acetate in quality control laboratories. [ABSTRACT FROM PUBLISHER]

Adsorption thin layer chromatography with densitometry has been established for the identification and the quantification of naproxen in tablets. UV densitometry was performed in absorbance mode at 230 nm. The presented method was validated by specificity, range, linearity, accuracy, precision, detection limit, quantitative limit, and robustness. The TLC-densitometric method was also compared with a pharmacopeial UV-spectrophotometric method for the assay of naproxen, and the results confirmed statistically that the TLC-densitometric method can be used as a substitute method. [ABSTRACT FROM AUTHOR]

Adsorption thin layer chromatography with densitometry has been established for the identification and the quantification of hydrocortisone in tablets. UV densitometry was performed in absorbance mode at 250 nm. The presented method was validated by specificity, range, linearity, accuracy, precision, detection limit, quantitative limit, and robustness. The TLC-densitometric method was also compared with a pharmacopeil UV-spectrophotometric method for the assay of hydrocortisone, and the results confirmed statistically that the TLC-densitometric method can be used as a substitute method. [ABSTRACT FROM AUTHOR]

NP-TLC and RP-TLC techniques with densitometry have been established for the identification and the quantification of ibuprofen in selected pharmaceutical preparations, namely: Nurofen, Ibuprom, and Ibum. Analyses were performed on silica gel 60 F254 plates using n-hexane-ethyl acetate-acetic acid, 15:5:0.7, v/v (NP-TLC) and on RP18 F254s plates using methanol-water, 9:1, v/v (RP-TLC). UV densitometry was performed at 200 and 224 nm for NP-TLC and RP-TLC analysis, respectively. NP-TLC and RP-TLC techniques with the densitometry and the spectrodensitometry applied to the investigation and the determination of ibuprofen in pharmaceutical preparations are selective, precise, and accurate. The techniques also realize the criterion of the linearity in the required range of ibuprofen concentrations. [ABSTRACT FROM AUTHOR]

Vitamin K1 (phylloquinone) was investigated with the use of reversed phase thin layer chromatography (RP-TLC) on RP8F254s, and RP18F254s (E. Merck) plates, using methanol as a mobile phase. It was stated that a larger amount of the bands on a chromatogram were obtained on RP8F254s plates than on RP18F254s plates. Six densitometric bands on RP8F254s plates were observed, where vitamin K1 had RF = 0.45 and λmax = 254 nm; however, the impurities had the RF values equal to 0.27, 0.54, 0.59, 0.62, and 0.75, respectively. It was stated that RP-TLC with densitometry and spectrodensitometry is a good method for the analysis of the qualitative composition of vitamin K1. [ABSTRACT FROM AUTHOR]

Thin layer chromatography with densitometry and spectrodensitometry was used to evaluate the stability of methyl nicotinate. Normal phase thin layer chromatography analysis was performed on silica gel 60 F254 with an acetone +n-hexane mobile phase. The investigations of chemical stability of methyl nicotinate were performed on silica gel 60 F254 at a temperature of 120°C, in an ethanolic solution stored at 8°C, as well as in aqueous and ethanolic solutions stored in ordinary- and quartz-flasks heated at 40°C and exposed to UV radiation (λ = 254 nm). Methyl nicotinate was only stable in aqueous and ethanolic solutions stored in ordinary flasks at 40°C and exposed to UV radiation (λ = 254 nm). [ABSTRACT FROM AUTHOR]

Phloroglucinol (P), niclosamide (N), salicylanilide (S) and thymol (T) were chromatographed on silica gel TLC plates with n-hexane-acetone in different volume proportions as mobile phases. Comparison and characterization of chromatographic spots of examined compounds on the basis of resolution (RS), separation factor (α), constant of the pair separation (RαF), and ΔRF values were discussed. The RS parameter, serving to evaluate the substance separation, was determined by visual and densitometric methods. It was proven that the RS parameter determined by the visual method for two adjacent substances is always larger than that determined by the densitometric method. It was stated that the densitometric method is correct, objective, and assures standard conditions for the parameter RS determination. [ABSTRACT FROM AUTHOR]

The spectrodensitograms of α-tocopherol acetate, α-tocopherol, cholecalciferol, estradiol, testosterone, and hydrocortisone on different chromatographic sorbents (silica gel 60, silica gel 60F254, mixture of silica gel 60 and kieselguhr F254, neutral aluminium oxide 60F254, neutral aluminium oxide 150F254, and RP18W) were compared. The resultant spectrodensitograms of the studied compounds indicate that applied sorbents have an influence on the wavelength of the obtained fundamental absorption band (λmax) and the additional absorption bands, as well as on their intensity values [AU]. This fact indicates the need for standaridization of the spectrodensitometric investigations regarding the applied chromatographic conditions. [ABSTRACT FROM AUTHOR]