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Two Simple, rapid, accurate and economical 'UV Spectrophotometry' and 'First Order Derivative' methods have been developed for determination of levofloxacin hemihydrate in bulk and tablets. In (10% v/v) acetonitrile, the ?max of the drug was found to be 288 nm. The same spectrum was derivatised into first order derivative, using UV probe software of instrument (Shimadzu-2450), at Δλ = 4. The amplitude of the trough was recorded at 297 nm. In both the proposed methods, levofloxacin hemihydrate follows linearity in the concentration range 2 - 12 μg/ml with a correlation coefficient of 0.9999. Assay results were in good agreement with label claim. The methods were validated statistically and by recovery studies. The relative standard deviation were found to be less than 2% with excellent precision and accuracy. [ABSTRACT FROM AUTHOR]

A simple, accurate, economical and reproducible procedure for simultaneous estimation of atorvastatin calcium and ezetimibe in their tablet dosage form has been developed using, Q-absorbance equation. The method involves, the absorbance measurement at 235.5 nm (iso-absorptive point) and 246.0 nm (λmax of atorvastatin calcium), in methanol. Both the drugs, obey Beer-Lambert's law in the concentration range of 5-25 µg/ml. The results of analysis have been validated statistically and by recovery studies. [ABSTRACT FROM AUTHOR]

Olmesartan medoxomil (OLME) belongs to a group of angiotensin II receptor blockers used as an antihypertensive agent and is currently being used for prevention of hypertension. This paper describes the validation and development of stability indicating RP-HPLC method for the determination of OLME in the presence of its degradation products generated from forced degradation study and characterization of degradation product (impurity). The assay involved gradient elution of OLME and an LC GC BDS C18 column (250 mmx4.5 mm, 5 μm particle size) was employed for loading the sample. The mobile phase A consisted of 7 ml triethylamine in 1000 ml water (pH adjusted to 3.0 with orthophosphoric acid) and B contained acetonitrile. Quantification was achieved with photodiode array detection at 257 nm. The chromatographic separation was obtained with a retention time of 6.72 min, and the method was linear in the range 50-150 µg/ml. The method was validated according to the ICH guidelines with respect to linearity, precision, accuracy, limit of detection (LOD), limit of quantification (LOQ), specificity and robustness. Impurity found in stressed and stability studies of olmesartan medoxomil in both drug substance and drug product are described. This degradation product is identified as 1-(biphenyl-4-ylmethyl)-1H-imidazole-5-carboxylic acid. An alkaline degradation pathway of Olmesartan Medoxomil, for the formation of this degradation product, has been proposed and the degradation product was characterized. [ABSTRACT FROM AUTHOR]

A dissolution method with high performance liquid chromatography (HPLC) analysis was validated for perindopril erbumine and indapamide in combination tablet formulation. The method was validated to meet requirements for a global regulatory filing and this validation included specificity, linearity, accuracy, precision, range, robustness and solution stability studies. The dissolution method, which uses a USP apparatus 1 with basket rotating at 100 rpm, 1000 ml of phosphate buffer, pH 6.8, as the dissolution medium, and reversed-phased HPLC was carried out at 50 °C on a 4.6 mmx250 mmx5 µm cyano column that contained USP packing L1 with acetonitrile:buffer 40:60 (v/v), pH 2.8, as mobile phase. UV detector was set at 225 nm. The method was found to be selective, linear, accurate and precise in the specified ranges. Intra-day and inter--day variability for method was <2% RSD. This method was successfully used for quantification of perindopril erbumine and indapamide combination tablet formulations. [ABSTRACT FROM AUTHOR]

A novel stability-indicating high-performance liquid chromatographic assay method was developed and validated for quantitative determination of ciprofibrate 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 mmx4.6 mm, 5 µm) advanced chromatography column, and methanol and water (90:10 v/v) as a mobile phase. The detection was carried out at a wavelength of 232 nm. The ciprofibrate was subjected to stress conditions of hydrolysis (acid and base), oxidation, photolysis and thermal degradation. Degradation was observed for ciprofibrate 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 ciprofibrate was from (98.65 to 100.01%) 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. [ABSTRACT FROM AUTHOR]

The present review covers a concise account of the synthesis of bioactive 2, 3-disubstituted-quinazoline-4(3H)-ones and the recent developments in the area of versatile quinazolinones with a special emphasis on new synthetic routes and strategies.

Caesalpinia decapetala is a wild plant found in the Sub-Himalayan tract and planted in hedges throughout in India. The bark of Caesalpinia decapetala is a rich source of tannins. It has been used in treatment of jaundice, stomach disorders and biliousness. The leaves and root are used as purgative and emmenagogue. The process described in this paper outline the extraction of gallic acid from Caesalpinia decapetala which is used as antioxidant and anti-inflammatory. Optimization of various solvent extraction parameters was performed to assess maximum yield of gallic acid from Caesalpinia decapetala wood. The extraction parameters optimized are solvent, temperature and time for extraction. Optimization was carried out by performing different sets of experiments. The most suitable conditions for extraction of gallic acid were found to be extraction at temperature (65-70(o)C), extraction time 48 hours and solvent composition Ethanol: Water (70:30). At these optimum extraction parameters the maximum yield of gallic acid obtained is 17.85%.

In different cultural groups, the hemiparasitic plants of the families Loranthaceae and Viscaceae (mistletoes) are frequently used in the treatment of hypertension and/or as diuretic agents. However, it remains unclear as to what commonality makes them diuretic agents or a remedy for hypertension. In this article, the diuretic activity of methanol extracts of Viscum articulatum (VA) Burm. f. and Helicanthus elastica (HE) (Ders.) Dans. in rats is reported. The extracts were administered orally at doses of 100, 200 and 400 mg/kg to rats that had been fasted and deprived of water for 18 hours. Investigations were carried out for diuretic, saluretic and natriuretic effects. The polyphenolic and triterpenoid contents were determined quantitatively using chemical assays and high performance liquid chromatography (HPLC) analysis, respectively. The extracts of VA and HE demonstrated significant and dose-dependent diuretic activity in rats. It was found that while VA mimics the furosemide pattern, HE demonstrated a dose-dependent increase in diuresis, along with an increase in potassium-sparing effects. Phytochemical analysis revealed that polyphenolics and triterpenoids, such as oleanolic acid and lupeol, are the major phytochemicals involved. It was also found that in different combinations, these phytochemicals differed in the way they influenced the electrolyte excretion. A higher content of polyphenolics in association with lower triterpenoid content was found to favor potassium-sparing effects.

Background: Toxicodendron pubescens is a botanical name of Rhus toxicodendron (Rhus tox). This plant is widely used in its homeopathically diluted form in the treatment of inflammatory and edematous conditions. In this study, various dilutions of Rhus tox including its crude form have been evaluated for their effects on immune response in the in vivo and in vitro experimental models., Methods: Rhus tox in the form of mother tincture, 6cH, 30cH, 200cH and 1000cH dilutions was tested through in vivo models including sheep red blood cells (SRBCs) induced cellular and humoral immune response in C57/BL6 mice. The effects of Rhus tox dilutions were also evaluated in vitro on the functions of human polymorphonuclear (PMN) cells such as phagocytosis and intracellular killing of Candida albicans, chemotaxis, and reduction of nitroblue tetrazolium (NBT) dye., Results: Rhus tox was found to intensify SRBCs induced antibody titer and delayed type hypersensitivity response in mice. Even higher dilutions such as 200cH and 1000cH were found to affect the immune response; however, the crude form, mother tincture, 6cH and 30cH dilutions revealed more potent effects than the 200cH and 1000cH dilutions. In in vitro assays, all the dilutions exerted stimulation of phagocytosis, candidacidal activity and chemotaxis of human PMN cells. The NBT dye reduction assay revealed that oxidative processes in the PMN cells are accelerated in the presence of Rhus tox. This study shows that Rhus tox possesses immunostimulatory activity in its crude form as well as in homeopathically diluted forms. These effects appeared to be concentration dependent as higher dilutions had less potent effects.

Antioxidant and cytotoxic activities of the methanolic and aqueous extracts of Caesalpinia pulcherrima wood were studied in in vitro models. Both extracts exhibited strong antioxidant activity, as evidenced by the low IC50 values in both 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide and superoxide scavenging methods; the values were found to be less or comparable to those of gallic acid, the standard used. To determine the cytotoxic activity, extracts were tested for toxic effects to brine shrimp larvae. In this assay, the methanolic extract had little effect, but aqueous extract was relatively toxic. The antioxidant and cytotoxic activities may be attributed to the total phenolic content in the wood.

The aim of the present study was to prepare mucoadhesive multiparticulate system for oral drug delivery using ionic gelation technique. Microspheres composed of various mucoadhesive polymers including HPMC of various grades like K4M, K15M, K100M, E50LV, Carbopol of grades 971P, 974P and polycarbophil were prepared. In this technique cross linking of sodium alginate with calcium chloride was done which retarded the release of drug from the mucoadhesive polymer. In the present work Metoprolol tararate was used as a model drug. Interaction studies performed using FTIR spectroscopy revealed that there was no drug to polymer interactions. The preliminary mucoadhesive strength studies performed for various polymers using rotating cylindrical method showed that HPMC had greater mucoadhesive properties than carbopol and polycarbophil. Microspheres so prepared were discrete, bulky, free flowing and showed an average encapsulation efficiency ranging from 50-60%. Particle size of the microspheres, as determined by the optical microscopy was found to be between 400-650 microm. The prepared formulations also exhibited a good mucoadhesive strength which was determined in in vitro conditions through falling film technique and was compared with ex vivo studies. The microspheres so prepared also exhibited a good swelling index which confirmed the strong mucoadhesive property of the formulation. Metoprolol release from the multiparticulate system was regulated and extended until 12 hours and exhibited a non fickian drug release kinetics approaching to zero order, as evident from the release rate exponent values which varied between 0.57 to 0.73. The stability studies performed on the optimized batches at 40 degrees C /75% RH for 90 days indicated no significant change in the physicochemical properties.