Abstract: The invention relates to a method and a device for producing nanoparticles of organic substances, in particular by controlled expansion of pressurized solutions. The method comprises: admixing the organic substance and a supercritical fluid to form a mixture at a first pressure; decreasing the first pressure gradually to a second pressure so that a flow of the mixture is formed and nucleation of the organic substance in the mixture is initiated; and, decreasing the second pressure to a third pressure, so that solidification of the fluid of the mixture, comprising the nucleated organic substance, is initiated. The device comprises: a pressure chamber (1) for a mixture of the organic substance and a supercritical fluid; a collection chamber (5) for the nanoparticles; an outlet tube (2) connecting the pressure chamber to the collection chamber (5); and, one or more second nozzles (6).

Abstract: The present invention relates to a device and a method for producing polymer fibers, in particular to nozzle-less electrospinning devices and methods to produce fibers and constructs thereof, wherein the nanofibers are generated by using pulsed and/or bursted ultrasound.

Abstract: The invention relates to a method and a device for producing nanoparticles of organic substances, in particular by controlled expansion of pressurized solutions. The method comprises: admixing the organic substance and a supercritical fluid to form a mixture at a first pressure; decreasing the first pressure gradually to a second pressure so that a flow of the mixture is formed and nucleation of the organic substance in the mixture is initiated; and, decreasing the second pressure to a third pressure, so that solidification of the fluid of the mixture, comprising the nucleated organic substance, is initiated. The device comprises: a pressure chamber (1) for a mixture of the organic substance and a supercritical fluid; a collection chamber (5) for the nanoparticles; an outlet tube (2) connecting the pressure chamber to the collection chamber (5); and, one or more second nozzles (6).

Abstract: Method for the performance of a mutagenicity test so that a cell population is subjected to a mutagen. As a result of this, a part of the population mutates, whereat the originally uniform cell population is differentiated into sub-populations. The variation of turbidity caused by the increase in the density of the differentiated cell populations is measured as a change in optical density by means of a photometer measuring vertically at a certain wavelength, and the quantity of cells in the sub-populations is determined as optical density. The absorbance values are measured in accordance with a pre-programmed time share system and a growth curve is formed out of the values as a function of time.