Abstract: The invention relates to a process for the production of morphologically uniform microcapsules that contain peptides, proteins or other water-soluble biologically active substances as active ingredients as well as microcapsules that are produced according to this process with a degree of concentration of between 3 to 30% by weight and a diameter ≦8 &mgr;m. According to the invention, biodegradable polymers are dissolved in a halogen-free solvent or solvent mixture, and the buffered active ingredient solution, which has a pH of between 6.0 to 8.0, is dispersed into this solution. Then, an aqueous solution that contains a surfactant (W/O/W-emulsion) is added to this W/O-emulsion, and the solvent is removed. The microcapsules that are produced with this process do not show any tendency toward agglomeration. The encapsulation efficiency of the process is approximately 90 to 95%.

Abstract: A process for increasing the stability of liposome suspensions that contain hydrophilic active ingredients is described, which is characterized in that the active ingredient that is to be encapsulated in the liposomes is metered such that 5% to 95% by weight of the active ingredient is present in unencapsulated form.

Abstract: The invention relates to gas-containing microparticles and nanoparticles that consist of biodegradable, synthetic polymers based on hydrophobized polysaccharides, agents that contain these particles for ultrasound diagnosis, and a process for the production of the particles and agents.

Abstract: The invention relates to a process for the production of morphologically uniform microcapsules that contain peptides, proteins or other water-soluble biologically active substances as active ingredients as well as microcapsules that are produced according to this process with a degree of concentration of between 3 to 30% by weight and a diameter≦8 &mgr;m. According to the invention, biodegradable polymers are dissolved in a halogen-free solvent or solvent mixture, and the buffered active ingredient solution, which has a pH of between 6.0 to 8.0, is dispersed into this solution. Then, an aqueous solution that contains a surface-active substance (W/O/W-emulsion) is added to this W/O-emulsion, and the solvent is removed. The microcapsules that are produced with this process do not show any tendency toward agglomeration. The encapsulation efficiency of the process is approximately 90 to 95%.

Abstract: The invention relates to gaseous microparticles for ultrasonic diagnosis, whose wall material is built up from block copolymers of polyesters of &agr;-, &bgr;- or &ggr;-hydroxycarboxylic acids with linear or star-shaped polyethylene glycols and optionally liquid crystals or whose wall material is built up from polyesters of &agr;-, &bgr;- or &ggr;-hydroxycarboxylic acids and liquid crystals, media that contain these particles for ultrasonic diagnosis, as well as a process for the production of the media and particles.