Diethylstilboesterol [DES] hormone in the Egyptian bovine muscles

One hundred bovine thigh muscle samples were examined for detection of diethyistilboesterol residues using spectrophotometric technique. Extraction of the samples was carried out according to the method recommended by Umberger et al [1963]. Diethylstilboesterol standard solution was prepared at concentration 2011/mi. For preparation of the working solution for spectrophotometric method 25m1 from the prepared solution were mixed with 18% potasium monohydrogen phosphate solution [V/V]. Finally the assay solution required for spectrophotometric method was prepared as well as the iradiation steps. Each sample extraction was measured and calculated. The obtaited results revealed that all samples were free from diethylistilboesterole residues. The results were discussed

Factors affecting the release of furosemide from agarose beads

Furosemide was loaded on agarose beads by immersing placebo beads in different drug methanolic solutions. The effects of both agarose and drug concentrations on the beads average size, drug content in the beads and the drug release were investigated. A correlation between the particle size of the dried beads and either agarose or drug concentration in the preparative solutions was obtained. The drug content of the beads was found to be dependent on the concentration of the preparative solutions of the beads. It was increased by decreasing the agarose preparative solution concentration while keeping that of the loading solution. However, at a constant agarose preparative solution concentration, as the loading solution concentration increased, the drug content increased

Powder characteristics, dissolution behavior and tableting of acetaminophen crystallized from water / cosolvent mixtures

Acetaminophen crystals harvested from water and/or cosolvent mixtures were evaluated for their powder characteristics, intrinsic dissolution rate [DR] and tableting behavior. The particle size of the crystals was dependent on the crystallization media. Crystals obtained from pure dioxane [D], isopropanol [IPA] or water possessed the smallest particle size. All the crystals provided excellent powder flowability as indicated by the low values of both angle of repose and the percentage compressibility. The crystals exhibited different IDR values and there was a correlation between either entropy of fusion [delta fus S] or water content and IDR of the crystals obtained from crystallization media containing IPA. Meanwhile, crystals obtained from acetone [A] or D containing solvents failed to exhibit this correlation. Direct compression of crystals produced tablets without capping. Tablet tensile strength increased with the decrease in water content of the crystals. Crystals obtained from the pure organic solvents produced the hardest tablets compared with that obtained from water or water/cosolvent mixtures. Crystals harvested from pure water exhibited friable tablets with the lowest tensile strength. A lack of correlation existed between delta fus S and tensile strength. Tablets prepared from crystals harvested from IPA containing solvents exhibited tensile strength which was inversely correlated with the mean particle size. Other tablets did not exhibit this compressible, highly flowable acetaminophen crystals with minimum water content could be obtained from pure A, D or IPA by controlled crystallization process

Formulation and ocular disposition of bromhexine hydrochloride ophthalmic preparations

Bromhexine hydrochloride [BH] a mucolytic agent was formulated in ophthalmic solutions, gels and ointments to be applied topically in the eyes to increase the mucus secretion in case of in flammation and keratoconjunctivitis. The effect of different ophthalmic vehicles, used in these formulation, on the in vitro release and ocular disposition of the drug in rabbit's eye has been studied. The results obtained revealed that, gel formulations [poloxamer 407 and sodium carboxymethylcellulose were superior to all other formulations for improving the ocular bioavailability of the drug. In case of ophthalmic solutions, the peak the time was attained after one hour while the peak level was elevated in the presence of 1% methylcellulose or polyvinyl alcohol. Semisolid vehicles, gels and ointments, exhibited a sustained activity of BH as the peak time was attained after two and three hours, respectively. Highly significant in vitro-in vivo correlations existed