Design of olanzapine/lutrol solid dispersions of improved stability and performances.

Eleven solid dispersions containing olanzapine, with carriers of different composition (Lutrol® F68, Lutrol® F127, Gelucire® 44/14), were prepared and examined by thermal (differential scanning calorimetry (DSC); thermomicroscopy (HSM)) and X-ray diffraction (XRD) analysis, both as fresh or aged (one year) samples. Drug and carriers were preliminarily selected in order to avoid problems related to the aging of the formulation, according to the solubility parameters of carriers and drug. These parameters make it possible to predict the low solubility of olanzapine in the carriers (alone or in mixtures).

Bimodal release of olanzapine from lipid microspheres.

Olanzapine was formulated as 10% (w/w) mixture with cutina to which stearic acid was added, ranging from 10% to 90% (w/w) of the total mass to control the drug release. The molten mixtures were processed by ultrasound-assisted spray-congealing technique, obtaining solid microspheres. The drug is stable under these conditions and only a partial miscibility in the solid state was observed by DSC between the two fatty materials with two separated melting endotherms in the thermograms: this can be due to the presence of two phases inside the solid dispersion.

Solubility and transdermal permeation properties of a dehydroepiandrosterone cyclodextrin complex from hydrophilic and lipophilic vehicles.

The permeation ability of a compound is due principally to its concentration in the vehicle and to its aptitude to cross the stratum corneum of the skin. In this work ex-vivo permeation studies on newly developed formulations containing dehydroepiandrosterone (DHEA) were carried out to investigate vehicles that increase drug permeation through the skin. To enhance the solubility of DHEA, its complex form with alpha-cyclodextrin was used.