Image analysis of lutrol/gelucire/olanzapine microspheres prepared by ultrasound-assisted spray congealing.

Nine systems were prepared containing Gelucire 50/13 and various amounts (9-18-36-45% w/w) of Lutrol F68 and F127 in the presence and in the absence of 10% w/w of olanzapine and formulated as a solid dispersion in the form of microspheres by ultrasound (US)-assisted spray congealing. Thermal analysis, using differential scanning calorimetry (DSC) and thermomicroscopy (HSM), suggested the presence of particles of reduced size of olanzapine precipitated inside the microspheres. The microspheres were also studied by means of electron microscopy (SEM) for their shape and aspect, by some image analysis parameters (fractal dimension) and using Energy-dispersive X-ray (X-EDS) and micro-Raman spectroscopy to qualitatively evaluate the composition of different points of the surface.

Diclofenac salts, part 6: release from lipid microspheres.

The release of diclofenac (20%, w/w) was studied from lipidic solid dispersions using three different chemical forms (acid, sodium salt, and pyrrolidine ethanol salt) and two different lipid carriers (Compritol 888 ATO or Carnauba wax) either free or together with varying amounts (10%-30%, w/w) of stearic acid. Microspheres were prepared by ultrasound-assisted atomization of the molten dispersions and analyzed by scanning electron microscopy, differential scanning calorimetry, and hot stage microscopy. The effects of different formulations on the resulting drug release profiles as a function of pH were studied and the results were discussed.

Effect of Aerosil on the properties of lipid controlled release microparticles.

Theophylline-loaded microparticles of a lipid carrier, Precirol ATO 5, were prepared by the ultrasonic spray-congealing method. The goal of the work was to investigate the effect of different concentrations and kind of colloidal silicon dioxide (Aerosil 90, 200 and 300) on the microparticle characteristics (particle size, drug loading, morphology and kinetics of release). The results showed that the introduction of Aerosil improved the drug distribution in the different particle sizes and that the mean diameter of the microparticles decreased with the viscosity of the suspension to be nebulized, especially that with Aerosil 300.

Characterization and taste-masking evaluation of acetaminophen granules: comparison between different preparation methods in a high-shear mixer.

The aim of this study was to prepare and to investigate acetaminophen taste-masked granules obtained in a high-shear mixer using three different wet granulation methods (method A: water granulation, method B: granulation with a polyvinylpyrrolidone (PVP) binding solution and method C: steam granulation). The studied formulation was: acetaminophen 15%, alpha-lactose monohydrate 30%, cornstarch 45%, polyvinylpyrrolidone K30 5% and orange flavour 5% (w/w). In vitro dissolution studies, performed at pH 6.

Improved dissolution behaviour of steam-granulated piroxicam.

In this paper we prepared and characterized improved release granulates containing Piroxicam and beta-cyclodextrins (1:2.5 molar ratio), obtained by steam-aided granulation, using a one-step rotogranulator, Rotolab. These granulates were compared to those prepared by traditional wet granulation, to the physical mixture, and to the kneaded and dry granulates.

Preparation and characterisation of ibuprofen-poloxamer 188 granules obtained by melt granulation.

The aim of this study was to prepare, by melt granulation, granules containing ibuprofen as a poorly water soluble model drug in order to improve its dissolution rate and its availability; lactose as a diluent and poloxamer 188 (Lutrol F68), as a new meltable hydrophilic binder, were used. The granules were prepared in a laboratory-scale high-shear mixer, using a jacket temperature of 50 degrees C and an impeller speed of 500 rpm. The particle size analysis shows that the main fraction was between 200 and 500 microm, while the determination of drug content indicated that ibuprofen was quite uniformly distributed in all the fractions.