Determination of Cefdinir by a stability-indicating liquid chromatographic method

A simple, fast, specific, stability-indicating, and precise reversed-phase liquid chromatographic method was developed for the determination of Cefdinir in its different dosage forms, i.e., capsules and suspensions. The method was developed and optimized by analyzing the placebo preparation, formulations, and degraded samples of the drug substance according to the International Conference on Harmonization. The proposed method can successfully separate the drug from degradation products formed under stress conditions along with pharmaceutical ingredients such as preservatives. The developed method was used successfully to determine Cefdinir in capsules and Insta-use suspensions. The developed method was found to be linear for a concentration range of 6-14 microg/mL. Average recoveries obtained with the method were 99.3 +/- 0.4 and 99.6 +/- 0.4% for Insta-use suspensions and capsules, respectively. The method was shown to be specific, precise, and robust.     

A validated liquid chromatographic method for estimation of solasodine in various Solanum species and market formulations

This paper describes an improved liquid chromatographic (LC) method involving a prechromatographic derivatization step for the estimation of solasodine from berries of various Solanum species, market samples of Solanum xanthocarpum herb, extract, and its market formulations. Solasodine has heterocyclic nitrogen but has no conjugated double bonds in its structure. However, in all reported LC methods, detection was made in the ultraviolet range of 200-213 nm. In the present study, a prechromatographic derivatization of solasodine was done by forming an ion-pair complex of the heterocyclic nitrogen using the acidic dye methyl orange and acetate buffer of pH 4.7. Detection could be made in the visible range at 530 nm in this method. The method was validated and successfully applied to determine solasodine content in various plant samples and polyherbal formulations. The relative standard deviation was found to be 0.025% for system precision, and 0.8% for the linearity of the method, and the correlation coefficient was 0.999. Plant samples and market formulations were analyzed and found to contain solasodine in the range of 0.113-0.227% (w/w) on a fresh weight basis in berries; 0.3-1.278% (w/w) and 0.412% (w/w) on a dry weight basis in S. xanthocarpum herb powder and extract, respectively; and 0.245-0.525% (w/w) on dry weight basis in formulations containing S. xanthocarpum herb powder. No matrix interference was encountered. The method was found to be accurate, with a mean recovery of 100.5 +/- 0.83%. The method has good reproducibility and was found to be suitable for estimation of solasodine.     

Spectrophotometric, difference spectroscopic, and high-performance liquid chromatographic methods for the determination of cefixime in pharmaceutical formulations

Three simple and sensitive spectrophotometric, difference spectroscopic, and liquid chromatographic (LC) methods are described for the determination of cefixime. The first method is based on the oxidative coupling reaction of cefixime with 3-methyl-2-benzothiazolinon hydrazone HCI in presence of ferric chloride. The absorbance of reaction product was measured at the maximum absorbance wavelength (wavelength(max)), 630 nm. The difference spectroscopic method is based on the measurement of absorbance of cefixime at the absorbance maximum, 268 nm, and minimum, 237 nm. The measured value was the amplitude of maxima and minima between 2 equimolar solutions of the analyte in different chemical forms, which exhibited different spectral characteristics. The conditions were optimized, and Beer's law was obeyed for cefixime at 1 to 16 microg/mL and 10 to 50 microg/mL, respectively. The third method, high-performance LC, was developed for the determination of cefixime using 50 mM potassium dihydrogen phosphate (pH 3.0)-methanol (78 + 22, v/v) as the mobile phase and measuring the response at wavelength(max) 286 nm. The analysis was performed on a Lichrospher RPC18 column. The calibration curve was obtained for cefixime at 5 to 250 microg/mL, and the mean recovery was 99.71 +/- 0.01%. The methods were validated according to the guidelines of the U.S. Pharmacopoeia and also assessed by applying the standard addition technique. The results obtained in the analysis of dosage forms agreed well with the contents stated on the labels.     

Novel TLC Densitometric Method for Quantification Of Solasodine in Various Solanum Species, Market Samples and Formulations

This paper describes a novel TLC densitometric method for the determination of solasodine in various Solanum species (Family Solanaceae). Solasodine does not give absorption in UV range. Hence, ion pair complex of solasodine and acid dye was spotted on TLC plates. A developing solvent with an organic acid ensured in situ color development of the complex which could be successfully quantified at 461 nm. Linearity was found to be in the range of 79.2–495 ng spot⁻¹ with correlation coefficient of 0.995. This method is reproducible, specific, eliminates post derivatization steps and the problem of background interference. The method was completely validated and applied to determine solasodine content in various herb samples, herb extract and their formulations. Accuracy of the method was found to be 98.54 ± 2.8%. No matrix interference was observed.     

Simultaneous Quantitation of Piperine and Piperlongumine in the Fruit of Piper longum Linn. by Validated High-Performance Thin-Layer Chromatography—Densitometric Method

JPC – Journal of Planar Chromatography – Modern TLC - The fruit of Piper longum Linn. (family: Piperaceae), known as pippali in India, is a reputed drug of Ayurveda (the Indian system...     

High-Performance Thin-Layer Chromatographic Method for the Simultaneous Quantification of Piperine,Piperlongumine, and 6-Shogaol in Trikatu Churna — An Ayurvedic Formulation

JPC – Journal of Planar Chromatography – Modern TLC - Trikatu Churna is an important formulation in Ayurveda — the Traditional System of Indian Medicine. It consists of fine...     

A validated quantitative thin-layer chromatographic method for estimation of diosgenin in various plant samples, extract, and market formulation

A sensitive and reproducible thin-layer chromatographic method has been developed for quantitation of diosgenin, a spiroketal sapogenin. The spots were visualized by spraying with modified anisaldehyde-sulfuric acid reagent. The concentration of anisaldehyde was reduced to 0.1% instead of 1%, and the concentration of sulfuric acid was kept at a minimum of 2%. This successfully reduced charring and background interference. The method was validated according to International Conference on Harmonization guidelines. The method was used for determination of diosgenin from dried samples of fenugreek seeds, leaves, stem, seed extracts, and a polyherbal antidiabetic formulation containing fenugreek powder as one of the ingredients. Increased detection sensitivity was observed with linearity from 98 to 588 ng/spot and a correlation coefficient (r2) of 0.988. The relative standard deviation value for linearity of the method was found to be 0.18%. The method was successfully applied to various plant samples of fenugreek (Methi) with a recovery of 98.11 +/- 1.4%. Dried plant samples and a market formulation were analyzed and found to contain diosgenin in the range of 0.529-0.658% (w/w) in fenugreek seed powders, 0.087% (w/w) in fenugreek leaf powder, 0.015 and 1.27% (w/w) in fenugreek stem powder and extract, respectively, and 0.586% (w/w) in a formulation containing fenugreek seed powder. No matrix interference was observed.