Optimization of process variables for phyllanthin extraction from Phyllanthus amarus leaves by supercritical fluid using a Box-Behnken experimental design followed by HPLC identification

The response surface methodology using the Box-Behnken design was established to describe supercritical carbon dioxide assisted extraction of phyllanthin from Phyllanthus amarus Schum and Thonn leaves prior to HPLC analysis. The effects of extraction pressure, temperature, modifier concentration and extraction time on the yield of phyllanthin were investigated. By solving the regression equation, the optimum conditions were as follows: extraction pressure 23.2 MPa, temperature 40 °C, methanol as modifier at a concentration 10 % and time 90 min. Under these conditions, the phyllanthin yield was 12.83 ± 0.28 mg g-1, which was in good agreement with the predicted values. Modifier concentration and extraction time showed a significant effect on the phyllanthin yield

Densitometric Determination of Risedronate Sodium in Tablets

An HPTLC method for analysis of risedronate sodium in bulk and pharmaceutical formulation has been established and validated. The analyte was separated on aluminium plates precoated with silica gel 60 F254 . The mobile phase was water-acetontrile-ammonia solution 9.3:0.40:0.3 (v/v). Quantification was done by densitometric scanning at 262 nm. Response was a linear function of risedronate asdium concentration in the range of 5 to 25 μg/mL. The limit of detection and quantification for risedronate sodium were 0.86 and 3.03 μg/mL respectively. Average recovery of risedronate sodium was 99.31, which shows that the method was free from interference from excipients present in the formulation. The established method enabled accurate, precise, and rapid analysis of risedronate sodium in bulk as well as pharmaceutical formulation.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Analgesic and anti-inflammatory activities of saponified fraction from Annona reticulata L. Bark

The saponified petroleum ether extract (SPE) of the Annona reticulata L. bark were studied for fatty acid composition by GC-MS analysis. Six fatty acids amounting 86.68% of the total contents were identified. The composition of saturated and unsaturated fatty acid was 22.10 % and 64.58 %, respectively. SPE at the doses of 12.5, 25 and 50 mg/kg body weight showed significant central as well as peripheral analgesic, along with anti-inflammatory activity.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Densitometric Determination of Risedronate Sodium in Tablets

An HPTLC method for analysis of risedronate sodium in bulk and pharmaceutical formulation has been established and validated. The analyte was separated on aluminium plates precoated with silica gel 60 F254 . The mobile phase was water-acetontrile-ammonia solution 9.3:0.40:0.3 (v/v). Quantification was done by densitometric scanning at 262 nm. Response was a linear function of risedronate asdium concentration in the range of 5 to 25 μg/mL. The limit of detection and quantification for risedronate sodium were 0.86 and 3.03 μg/mL respectively. Average recovery of risedronate sodium was 99.31, which shows that the method was free from interference from excipients present in the formulation. The established method enabled accurate, precise, and rapid analysis of risedronate sodium in bulk as well as pharmaceutical formulation.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Stability-indicating HPLC determination of pramipexole dihydrochloride in bulk drug and pharmaceutical dosage form

A novel stability-indicating high-performance liquid chromatographic assay method was developed and validated for quantitative determination of pramipexole dihydrochloride in bulk drugs and in pharmaceutical dosage form in the presence of degradation products. An isocratic, reversed phase HPLC method was developed to separate the drug from the degradation products, using an Ace5-C18 (250×4.6 mm, 5 µm) advance chromatography column, and 10 mmol L-1 ammonium acetate and acetonitrile (75:25 v/v) as a mobile phase. The detection was carried out at a wavelength of 260 nm. The pramipexole was subjected to stress conditions of hydrolysis (acid, base), oxidation, photolysis and thermal degradation. Degradation was observed for pramipexole in base, in acid and in 30% H2O2. The drug was found to be stable in the other stress conditions attempted. The degradation products were well resolved from the main peak. The percentage recovery of pramipexole was from (99.87 to 99.98%) in the pharmaceutical dosage form. The developed method was validated with respect to linearity, accuracy (recovery), precision, system suitability, specificity and robustness. The forced degradation studies prove the stability indicating power of the method

Optimization of supercritical fluid extraction and HPLC identification of wedelolactone from Wedelia calendulacea by orthogonal array design

The purpose of this work is to provide a complete study of the influence of operational parameters of the supercritical carbon dioxide assisted extraction (SC CO2E) on yield of wedelolactone from Wedelia calendulacea Less., and to find an optimal combination of factors that maximize the wedelolactone yield. In order to determine the optimal combination of the four factors viz. operating pressure, temperature, modifier concentration and extraction time, a Taguchi experimental design approach was used: four variables (three levels) in L9 orthogonal array. Wedelolactone content was determined using validated HPLC methodology. Optimum extraction conditions were found to be as follows: extraction pressure, 25 MPa; temperature, 40 °C; modifier concentration, 10% and extraction time, 90 min. Optimum extraction conditions demonstrated wedelolactone yield of 8.01 ± 0.34 mg/100 g W. calendulacea Less. Pressure, temperature and time showed significant (p < 0.05) effect on the wedelolactone yield. The supercritical carbon dioxide extraction showed higher selectivity than the conventional Soxhlet assisted extraction method

Oxalic acid catalyzed solvent-free synthesis of <img src='/image/spc_char/alpha.gif' border=0>-amidoalkyl-β-naphthols

71-73An efficient one-pot synthesis of -amidoalkyl-β-naphthols is described. This involves the three-component reaction of β-naphthol, aromatic aldehydes and amide or urea in the presence of a catalytic amount of oxalic acid under solvent-free condition