Method for the gentle production of ultrafine particle suspensions and ultrafine particles and the use thereof

摘要

The invention describes a multistage process, for producing particles with an average particle size from 50 nm to 1000 nm in a very effective and gentle manner, wherein the solid substance (active substance) is dissolved in a solvent, this liquid containing the solid substance (active substance) in dissolved form is then frozen very rapidly, the solvent/solvents used are optionally removed from the frozen matrix obtained in a (freeze-)drying process (lyophilization) or the frozen matrix is further processed directly, the solid matrix (frozen or lyophilized) is dispersed in an external phase, a liquid medium, which can be water, a mixture of water with water-miscible liquids or a non-aqueous liquid, and the resulting dispersion is then immediately exposed to high shear and/or cavitation forces, and the forces applied result in stabilization or comminution of the resulting particles in the nanometer range. The method described is particularly suitable for the processing of thermolabile and sensitive substances, since it can be performed in a manner very gentle to the product, and the wear on the devices used can be markedly decreased by reduction of the necessary cycle number or by reduction of the power density to be applied. The nanoparticles obtained can be used in various fields, e.g. in the pharmaceutical field, in the cosmetic industry, the foodstuffs industry, the textile industry and other industrial fields.

主权项

1. Method for the gentle production of ultrafine particle suspensions comprising:
dissolving a substance in solid form that is insoluble in water or poorly soluble in water in a suitable solvent to form a solution comprising the substance dissolved in the solvent; freezing the solution to form a solid matrix of the frozen solution; dispersing the solid matrix of the frozen solution in the frozen state in a dispersion medium comprising water to form a first dispersion of frozen solution particles dispersed in the dispersion medium; and applying high forces in the range of 109 to 1013 W/m3 using high pressure homogenization to the first dispersion prior to the melting of the frozen solution particles to disintegrate and melt the frozen solution particles, and when the frozen solution is melted the dispersion medium causes precipitation of a solid substance in a mixture of the solvent and the dispersion medium to form a second particle suspension comprising solid substance particles suspended in the mixture of the solvent and dispersion medium and the application of high forces during the precipitation inhibits growth of a size of the solid substance particles, to form the solid substance particles having an average particle size, determined by photon correlation spectroscopy (PCS), of below 1000 nm.