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O/W creams prepared in three mechanical conditions (F with a hand blender; S turbomixer; T vacuum turbo-emulsor) produced different dispersion grades of the internal phase and different rheological characteristics by using surfactants of different chemical nature (polyoxyethylene-cetostearyl alcohols and polyglyceryl-3-methylglucose distearate). Three tests were used (an in vitro release test across a porous membrane; an in vitro simulated absorption test across a porous membrane impregnated with isopropyl myristate; an in vivo absorption test based on the intensity and duration of the erythema produced by methyl nicotinate after application of the cream on the skin) to assess whether the different physical characteristics influence drug availability from the creams. The different physical characteristics due to the mechanical conditions of emulsifying and gelification appeared not to influence drug release and in vivo absorption. [Copyright &y& Elsevier]

Two series of O/W creams having the same general formulation were prepared in three different mechanical conditions (F with an hand blender; S with a turbomixer; T with a vacuum turbo emulsor) using two types of surfactants, polyoxyethylene-cetostearyl alcohols and polyglyceryl-3-methylglucose-distearate. By means of microscopic image analysis it was possible to point out the dispersion grade of the oil internal phase increasing with the energy applied under the conditions of manufacture (F

Sugars and sweeteners are common ingredients in foods and also in pharmaceutical industries. They are soluble and sticky ingredients and their processing in granulators may be difficult since they can easily adhere to mixer walls or lead to uncontrolled granule growth. The purpose of this research was to evaluate the feasibility of the high shear wet granulation process and to find the optimal amount of binder by studying the granulation performances of four sugars: mannitol, sorbitol, xylitol and sucrose in different amounts. Sugar interactions with the liquid binder and solid carrier were carefully characterized. The increased viscosity of the liquid bridges, due to the partial solubilization of the sugars, was found to play a major role in the agglomeration process since it controls the liquid mobility and its distribution. Experiments demonstrate the feasibility of the process and the ability of mixer torque rheometer to predict the optimal binder amount. [ABSTRACT FROM AUTHOR]

Mesoporous silica particles prepared through a simplified Stöber method and low temperature solvent-promoted surfactant removal are evaluated as dissolution enhancers for poorly soluble compounds, using a powerful anticancer agent belonging to pyrroloquinolinones as a model for anticancer oral therapy, and anti-inflammatory ibuprofen as a reference compound. Mesoporous powders composed of either pure silica or silica modified with aminopropyl residues are produced. The influence of material composition and drug chemical properties on drug loading capability and dissolution enhancement are studied. The two types of particles display similar size, surface area, porosity, erodibility, drug loading capability and stability. An up to 50% w/w drug loading is reached, showing correlation between drug concentration in adsorption medium and content in the final powder. Upon immersion in simulating body fluids, immediate drug dissolution occurred, allowing acceptor solutions to reach concentrations equal to or greater than drug saturation limits. The matrix composition influenced drug solution maximal concentration, complementing the dissolution enhancement generated by a mesoporous structure. This effect was found to depend on both matrix and drug chemical properties allowing us to hypothesise general prediction behaviour rules. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this research was to determine the effects of some important drug properties (such as particle size distribution, hygroscopicity and solubility) and process variables on the granule growth behaviour and final drug distribution in high shear wet granulation. Results have been analyzed in the light of widely accepted theories and some recently developed approaches. A mixture composed of drug, some excipients and a dry binder was processed using a lab-scale high-shear mixer. Three common active pharmaceutical ingredients (paracetamol, caffeine and acetylsalicylic acid) were used within the initial formulation. Drug load was 50% (on weight basis). Influences of drug particle properties (e.g. particle size and shape, hygroscopicity) on the granule growth behaviour were evaluated. Particle size distribution (PSD) and granule morphology were monitored during the entire process through sieve analysis and scanning electron microscope (SEM) image analysis. Resistance of the wet mass to mixing was furthermore measured using the impeller torque monitoring technique. The observed differences in the granule growth behaviour as well as the discrepancies between the actual and the ideal drug content in the final granules have been interpreted in terms of dimensionless quantity (spray flux number, bed penetration time) and related to torque measurements. Analysis highlighted the role of liquid distribution on the process. It was demonstrated that where the liquid penetration time was higher (e.g. paracetamol-based formulations), the liquid distribution was poorer leading to retarded granule growth and selective agglomeration. On the other hand where penetration time was lower (e.g. acetylsalicylic acid-based formulations), the growth was much faster but uniformity content problem arose because of the onset of crushing and layering phenomena. [Copyright &y& Elsevier]

Silver-111 (111Ag, t 1/2 = 7.47 d) is a β − emitter suitable for targeted cancer therapy due to favourable decay properties. The production of no-carrier added 111Ag via Isotope Separation On-Line (ISOL) technique is being investigated at the Legnaro National Laboratories of the Italian Institute of Nuclear Physics (ISOLPHARM project). Stable Cadmium-111 (111Cd) is co-produced as isobaric contaminant, hence a chemical separation process must be developed to selectively harvest 111Ag. In this study, a chromatographic procedure employing the commercially available CL resin was investigated by using stable Ag+ and Cd2+. Results indicate that CL resin allows to efficiently separate Ag+ from Cd2+ and recover the former with high yields. • Silver-111 (t 1/2 = 7.47 days) is a β − emitting radionuclide suitable for cancer therapy. • During 111Ag production via ISOL method, 111Cd is co-produced. • Chromatographic method using commercially available CL resin was developed to separate silver from cadmium. [ABSTRACT FROM AUTHOR]