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Intensive dry powder coating (mechanofusion) with tablet lubricants has previously been shown to give substantial powder flow improvement. This study explores whether the mechanofusion of magnesium stearate (MgSt), on a fine drug powder can substantially improve flow, without preventing the powder from being directly compacted into tablets. A fine ibuprofen powder, which is both cohesive and possesses a low-melting point, was dry coated via mechanofusion with between 0.1% and 5% (w/w) MgSt. Traditional low-shear blending was also employed as a comparison. No significant difference in particle size or shape was measured following mechanofusion. For the low-shear blended powders, only marginal improvement in flowability was obtained. However, after mechanofusion, substantial improvements in the flow properties were demonstrated. Both XPS and ToF-SIMS demonstrated high degrees of a nano-scale coating coverage of MgSt on the particle surfaces from optimized mechanofusion. The study showed that robust tablets were produced from the selected mechanofused powders, at high-dose concentration and tablet tensile strength was further optimized via addition of a Polyvinylpyrrolidone (PVP) binder (10% w/w). The tablets with the mechanofused powder (with or without PVP) also exhibited significantly lower ejection stress than those made of the raw powder, demonstrating good lubrication. Surprisingly, the release rate of drug from the tablets made with the mechanofused powder was not retarded. This is the first study to demonstrate such a single-step dry coating of model drug with MgSt, with promising flow improvement, flow-aid and lubrication effects, tabletability and also non-inhibited dissolution rate. [ABSTRACT FROM AUTHOR]

Objectives The objectives of this project were the use of surface energy distributions in: distinguishing the effects of magnesium stearate on the surface energy of lactose processed by two methods: mixing in a Turbula and mechanofusion; characterising surface energy of materials before and after micronisation; and understanding surface energy changes of micronised lactose before and after storage at high relative humidity (RH). Methods Heptane, octane and nonane were used to determine nonpolar surface energy, and dichloromethane and ethyl acetate were used to determine polar surface energy in inverse gas chromatography at finite dilution. Key findings The total surface energy of lactose decreased more after mechanofusion with magnesium stearate than mixing in Turbula. The nonpolar surface energy of indometacin increased while polar and total surface energies decreased after micronisation. The nonpolar, polar and total surface energies and work of cohesion of micronised lactose decreased after storage at 75%RH for three months. Conclusions The surface energy distributions determined at finite dilution successfully distinguished and revealed more information than infinite dilution on surface energy changes in materials undergoing different pharmaceutical processes such as mixing, mechanofusion, micronisation and storage at high RH. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the mechanism of action of ternary components within dry powder aerosols. Methods. Ternary interactive mixtures were prepared containing salbutamol sulphate (SS), coarse lactose carriers and either micronized lactose (ML) or micronized glucose (MG). In vitro drug and excipient aerosol deposition was performed using a twin-stage impinger (TSI) at 60 L/min with a Rotahaler device. Adhesional properties of the lactose carrier were examined using an atomic force microscope (AFM) colloidal probe technique. Result. The fine particle fraction (FPF) from ternary mixtures were dependent upon carrier type (p < 0.001), ternary concentration (p < 0.001) and ternary component type (p < 0.05). Ternary mixtures produced higher FPF than binary mixtures, except those containing Superfine (SF), which was attributed to the high proportion of intrinsic fine carrier particles. The higher FPF obtained from ternary mixtures was independent of the mixing order (p = 0.08). Increased adhesion force was observed on the carrier surface following the addition of ternary components (p < 0.001). Conclusion. The results confirm that ternary components increase aerosol deposition of powder mixtures. Some results were not entirely consistent with the saturation of active site theory and a hypothesis involving competitive and multilayer adhesion was proposed and requires further testing. [ABSTRACT FROM AUTHOR]

Discusses the role of industrial scientists in establishing international programs in energy research and development. Need for a change in the worldwide energy situation as of March 18, 1975; Role of governments in setting up international cooperative efforts aimed at developing the world's energy resources; Goals that should be included in the energy projects.

The author reflects on the status of Pharmacy Education in Australia in 2008. He claims that there is already 16 pharmacy courses consisting of undergraduate bachelor and postgraduate master courses in the country. He explains that these 16 pharmacy courses vary from one from the other as far as the enabling sciences, applied pharmaceutical sciences, clinical pharmacy, and pharmacy practice are concerned.

The article discusses a study that confirms the safety and efficacy of drug-eluting stents (DES). It presents the Melbourne Interventional Group's (MEG) registry data for DES use in selected public hospitals in Melbourne, Victoria over a 4-year period. It reports on the decrease in the number of DES implantation in 2007-2008, and highlights the changes in DES use in public hospitals. It details the requirements for DES use in state hospitals in Victoria.

Presents two cases of ischiorectal abscesses caused by ingested bones. Overview of ischiorectal abscess; Presenting symptoms of the patients; Variety of ingested foreign bodies that have been described and retrieved from the anal canal.