Posted by admin on Apr 1, 2011 in |
2-amino-4-chlorophenol (ACP) is a synthetic precursor of the skeletal muscle relaxant; chlorzoxazone. A rapid simple colorimetric method was proposed for the determination of 2-amino-4-chlorophenol as a potential impurity in chlorzoxazone bulk powder via its reaction with 4-aminoantipyrine in presence of alkaline oxidizing agent (K3[Fe(CN)6] / NH3) and measuring the produced red color at 520 nm. Different experimental parameters affecting the formation of the reaction product were studied. The study included the effect of volumes of the used reagents as well as the effect of time on the formation and stability of the reaction product. The formation constant (Kf) of the reaction product was found to be 1.2 x 104 indicating a very stable reaction product. Moreover, the Gibbs free energy change of the reaction (ΔG) was found to be -2.3 x 104 K.J/mole pointing out to the spontaneous nature of the reaction. The method was successfully applied for the trace analysis of the studied compound in spiked chlorzoxazone powder. The calibration graph was linear over the range of 1-20 µg/ml with average recovery of 100.58±0.89, detection limit of...
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Posted by admin on Apr 1, 2011 in |
The global demand of concrete is increasing every year and generally is considered as most consumed material on earth. But concrete is vulnerable to deterioration, corrosion, and cracks, and the consequent damage and loss of strength requires immensely expensive remediation and repair. One such mechanism that receives increasing attention in recent years is the ability for self-repair. So a novel and inexpensive method is available for overcoming the mentioned problem. The microbial concrete makes use of calcite precipitation by bacteria. A specific group of alkali-resistant spore-forming bacteria related to the genus Bacillus was selected for this purpose, the phenomenon is called microbiologically induced calcite precipitation (MICP). Bacillus Pasteruii, a common soil bacterium, can induce the precipitation of calcite. Due to its inherent ability to precipitate calcite continuously, bacterial concrete can be called as a “Smart Bio Material” for repairing...
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Posted by admin on Apr 1, 2011 in |
Solid dispersions traditionally have been used as effective methods to improve the dissolution properties and bioavailability of poorly water-soluble drugs. Furosemide a loop diuretic belonging to Biopharmaceutical Classification System (BCS) Class IV, has very poor water solubility. The aim of the present study was to improve the solubility and dissolution rate of a poorly water-soluble drug, furosemide, by solid dispersion technique as well as to evaluate the potential of Eudragit RL-100, RS-100 and Drug coat L -100, S -100 (methacrylic acid polymers) as carriers for solid dispersions. Solid dispersions were prepared by solvent evaporation technique. The solid dispersions were characterized for particle size, particle size distribution, solubility studies and interaction studies such as FTIR spectroscopy. Solid state characterizations i.e., X-Ray diffraction study; Differential Scanning Calorimetry and Scanning Electron Microscopy were also carried out for the best formulation. In contrast to the very slow dissolution rate of pure furosemide, the dispersion of the drug in the polymer considerably enhanced solubility. The aqueous solubility of furosemide was favoured by formulating it...
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Posted by admin on Apr 1, 2011 in |
Three Simple, precise, accurate and economical UV methods have been developed and validated for the quantitative estimation of Dorzolamide HCl in bulk and pharmaceutical dosage form. Dorzolamide HCl has the absorbance maxima at 253 nm in zero order spectra (Method A). In the first order derivative spectra, showed absorbance maxima at 238 nm (Method B) and in the second order derivative spectra, showed peak maxima at 278 nm (Method C). Distilled water was used as solvent for all the methods. Beer’s law was found to be obeyed in the concentration range of 3-24 μg/ml. The developed method was validated according to ICH guidelines and was found to be accurate, economic and precise. The proposed method can be successfully applied for the estimation of Dorzolamide HCl in bulk and pharmaceutical dosage...
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Posted by admin on Apr 1, 2011 in |
Repaglinide is widely used as a hypoglycemic drug for the treatment of chronic type 2 diabetes mellitus. The objective of the present study was to improve the bioavailability of repaglinide by nasal delivery using degradable starch microspheres. Degradable starch microspheres were prepared by an emulsion polymerization method and formaldehyde was used as a cross linking agent. The formulations were characterized for their encapsulation efficiency, surface morphology, particle size and ex vivo drug release pattern. The relative bioavailability in rats was studied in lead formulations. The repaglinide microspheres formulations showed significant increase in...
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