Abstract: The invention relates to a method for cultivating photoautotrophic micro-organisms, comprising the following steps: provision of a photosynthesis layer, which contains a photosynthesis medium and photoautotrophic micro-organisms suspended therein, in a closed accommodation space having a gas-diffusion-inhibiting outer boundary, wherein the photosynthesis layer has an average thickness of no more than 10 mm; exposure of the photosynthesis layer without eddying or feeding through a gas in the photosynthesis medium while limiting the diffusive gas exchange of the accommodation space by the environment, wherein the supply of micro-organisms in the photosynthesis medium with hydrogen carbonate ions is maintained by storing hydrogen carbonate ions in the photosynthesis medium and/or providing a photosynthesis substrate in the form of carbon dioxide and hydrogen carbonate from a cell-free carbon storage medium outside the photosynthesis layer; and conducting a gas formed during photosynthesis out of the accommodatio

Abstract: The invention relates to a research photobioreactor for growth at extremely high cell densities in axenic cultures of cyanobacteria and microalgae exposed to a high light intensity. A hydrophobic gas-permeable first membrane situated at the bottom of the reaction chamber serves for the entry of CO2 into the cell suspension. The first membrane separates the CO2 containing gaseous phase in a basis chamber from the cell suspension that covers the membrane. It has a permeability coefficient for the gases of air many times that of the physically feasible rate of absorption of these gases in water. The turbulent flow within the cell suspension is obtained by shaking. A high shearing rate hereby realized increases the CO2 absorption rate in the liquid phase close to the membrane, thus avoiding C-limitation. A porous hydrophobic gas-permeable second membrane separates the reaction chamber from at least one gas exchange chamber.

Abstract: A process for cultivation of photoautotrophic microorganisms is proposed comprising providing a photosynthesis layer (2) containing a photosynthesis medium and photoautotrophic microorganisms suspended therein in a closed inclusion space with an outer border (1) restricting gas diffusion, whereat the photosynthesis layer exhibits a mean thickness of not more than 10 mm, exposing the photosynthesis layer (2) to light without whirling a gas within or piping a gas through the photosynthesis medium under restriction the of the diffusive gaseous exchange between the inclusion space with the surrounding, whereat the supply of the microorganisms with bicarbonate ions is realized by storage of bicarbonate ions in the photosynthesis medium and/or delivery of a photosynthesis substrate in the kind of carbon dioxide and/or bicarbonate from a cell free carbon storage medium (4) localized outside of the photosynthesis medium, and channeling away the gas volume formed at photosynthesis.

Abstract: A micro-dialysis probe extending longitudinally between a proximal probe opening and a distal probe tip and having a supply line and a drainage line for a drip-feed solution. A tube may be provided for supporting the drainage line. A dialysis section, wherein the flow channel for the drip-feed solution experiences an inversion, is formed generally between the supply line and the drainage line, in the vicinity of the distal probe tip. The supply line and the drainage line are respectively arranged substantially side by side and together form the probe shaft of the micro-dialysis probe.

Abstract: The invention relates to measuring the concentration of analytes with the aid of an oxidase in an immersion sensor situated in a fluid or in a matrix containing fluid. Oxygen diffuses into the enzyme layer from within, from a gas-filled space connected to the atmosphere and/or to an oxygen reservoir. This enables oxygen saturation of the oxidase in a low-oxygen or oxygen-free medium and/or at high analyte concentrations. The analyte diffuses into the enzyme layer in a channel or a number of channels which contain(s) water and limit(s) diffusion, wherein the channel/channels on the surface of the sensor is/are filled with a protein-impermeable, hydrophilic matrix. By increasing the channel cross-section on the surface of the sensor and/or by connecting the channel/channels to a protein-impermeable, porous, hydrophilic layer on the surface of the sensor, the effect of outer deposits on the diffusion resistance of the analyte is reduced.

Abstract: The invention refers to a method for control of a volume flow in an osmotic micropump and an osmotic micropump. According to the invention, the osmotically driven volume flow of the solvent through the sempipermeable diaphragm of an osmotic micropump is controlled by the transfer of a solute, which is not freely permeable through the diaphragm, from a source chamber to the pump's delivery chamber. According to the invention, the delivery chamber is formed as a dilution chamber, wherein the solution is flow out along a convective dilution path close to the semipermeable diaphragm. Due to the entrance of the solvent, a stationary osmotic gradient can be achieved along the convective flow path in the dilution chamber. The invention allows the maintenance and control of the flow rate. It is able to move a volume which is large in comparison to the combined volume of the source chamber and the dilution chamber.

Abstract: The invention relates to a method for preserving samples and disrupting cells which can be employed for the preparation of the extraction of nucleic acids from live cells, cell aggregates and tissue samples, and to a kit for carrying out the method. The method includes the introduction of live cells, cell aggregates or tissue samples whose nucleic acids are to be extracted into an excess of water-miscible and volatile organic liquid. The saturation of the sample with the organic liquid has an advantageous effect on the extraction of the nucleic acids, which is subsequently carried out in an aqueous medium. The mechanical cell disruption is facilitated by the virtually complete removal of the water from the cells. The biomembranes are dissolved in the organic liquid. tRNA and other RNA fractions with a low degree of polymerization, which are capable of permeating across the cell wall, can be extracted selectively without mechanical disruption.

Abstract: A micro-dialysis probe extending longitudinally between a proximal probe opening and a distal probe tip and having a supply line and a drainage line for a drip-feed solution. A tube may be provided for supporting the drainage line. A dialysis section, wherein the flow channel for the drip-feed solution experiences an inversion, is formed generally between the supply line and the drainage line, in the vicinity of the distal probe tip. The supply line and the drainage line are respectively arranged substantially side by side and together form the probe shaft of the micro-dialysis probe.

Abstract: A micro-dialysis probe extending longitudinally between a proximal probe opening and a distal probe tip and having a supply line and a drainage line for a drip-feed solution. A tube may be provided for supporting the drainage line. A dialysis section, wherein the flow channel for the drip-feed solution experiences an inversion, is formed generally between the supply line and the drainage line, in the vicinity of the distal probe tip. The supply line and the drainage line are respectively arranged substantially side by side and together form the probe shaft of the micro-dialysis probe.

Abstract: The invention relates to an assay method and a fluid microsystem for carrying out said assay method, in particular, for carrying out miniaturized affinity tests in a micro-array format. According to said invention, a liquid phase comprising at least one type of detectable high-molecular weight soluble substance, for example a labeled reaction partner or product of an affinity reaction is displaced by the hydraulic effect of a high-molecular weight osmotic agent on an ultrafiltration membrane towards a miniaturized measuring chamber defined thereby. The fraction of the detectable high-molecular weight substance(s) is concentrated in the measuring chamber, while the dissolved low-molecular weight components are removed with the solvent through the membrane pores, thereby making it possible to attain a high detection sensitivity.

Abstract: This invention relates to an automatic sample collector for liquids which are discharged from a chromatographic column, a dialysis apparatus, or a reaction container, for example, and are consecutively collected at a give volume division, a method for collecting samples of a liquid in a predefined chronological sequence, and uses of the inventive sample collector. The volume is divided by assigning one or several gas-permeable liquid barriers (4, 5) to each collection container (3). The sample collector can be produced as one piece which is for single use and is made of polypropylene, Teflon, or other suitable materials. The inventive sample collector has the advantage that it requires no source of energy and can be autoclaved and miniaturized, among other things. The design of the inventive sample collector makes it possible to keep the content of the collection containers free from oxygen or immediately freeze the liquid flowing into the collection containers.

Abstract: The invention relates to measuring the concentration of analytes with the aid of an oxidase in an immersion sensor situated in a fluid or in a matrix containing fluid. Oxygen diffuses into the enzyme layer from within, from a gas-filled space connected to the atmosphere and/or to an oxygen reservoir. This enables oxygen saturation of the oxidase in a low-oxygen or oxygen-free medium and/or at high analyte concentrations. The analyte diffuses into the enzyme layer in a channel or a number of channels which contain(s) water and limit(s) diffusion, wherein the channel/channels on the surface of the sensor is/are filled with a protein-impermeable, hydrophilic matrix. By increasing the channel cross-section on the surface of the sensor and/or by connecting the channel/channels to a protein-impermeable, porous, hydrophilic layer on the surface of the sensor, the effect of outer deposits on the diffusion resistance of the analyte is reduced.

Abstract: The invention relates to measuring the concentration of analytes with the aid of an oxidase in an immersion sensor situated in a fluid or in a matrix containing fluid. Oxygen diffuses into the enzyme layer from within, from a gas-filled space connected to the atmosphere and/or to an oxygen reservoir. This enables oxygen saturation of the oxidase in a low-oxygen or oxygen-free medium and/or at high analyte concentrations. The analyte diffuses into the enzyme layer in a channel or a number of channels which contain(s) water and limit(s) diffusion, wherein the channel/channels on the surface of the sensor is/are filled with a protein-impermeable, hydrophilic matrix. By increasing the channel cross-section on the surface of the sensor and/or by connecting the channel/channels to a protein-impermeable, porous, hydrophilic layer on the surface of the sensor, the effect of outer deposits on the diffusion resistance of the analyte is reduced.

Abstract: The invention relates to an assay method and a fluid microsystem for carrying out said assay method, in particular, for carrying out miniaturized affinity tests in a micro-array format. According to said invention, a liquid phase comprising at least one type of detectable high-molecular weight soluble substance, for example a labeled reaction partner or product of an affinity reaction is displaced by the hydraulic effect of a high-molecular weight osmotic agent on an ultrafiltration membrane towards a miniaturized measuring chamber defined thereby. The fraction of the detectable high-molecular weight substance(s) is concentrated in the measuring chamber, while the dissolved low-molecular weight components are removed with the solvent through the membrane pores, thereby making it possible to attain a high detection sensitivity.

Abstract: An apparatus for measuring the viscosity of a fluid having a first rigid member extending from a body of semiconductor material and provided with a first conductive path and a second resiliently flexible member provided with a second conductive path and arranged in cantilever fashion over the rigid member. At least one of the conductive paths may be selectively energized to brig about relative movement between the rigid and flexible member. Subsequent deenergization of the path causes the resiliently flexible member to return to its initial position, the rate of return being measured to derive a signal representative of the viscosity. Also described are methods of carrying out the measurement and of fabricating the apparatus.

Abstract: The invention refers to a method for control of a volume flow in an osmotic micropump and an osmotic micropump. According to the invention, the osmotically driven volume flow of the solvent through the sempipermeable diaphragm of an osmotic micropump is controlled by the transfer of a solute, which is not freely permeable through the diaphragm, from a source chamber to the pump's delivery chamber. According to the invention, the delivery chamber is formed as a dilution chamber, wherein the solution is flow out along a convective dilution path close to the semipermeable diaphragm. Due to the entrance of the solvent, a stationary osmotic gradient can be achieved along the convective flow path in the dilution chamber. The invention allows the maintenance and control of the flow rate. It is able to move a volume which is large in comparison to the combined volume of the source chamber and the dilution chamber.

Abstract: A micro-dialysis probe extending longitudinally between a proximal probe opening and a distal probe tip and having a supply line and a drainage line for a drip-feed solution. A tube may be provided for supporting the drainage line. A dialysis section, wherein the flow channel for the drip-feed solution experiences an inversion, is formed generally between the supply line and the drainage line, in the vicinity of the distal probe tip. The supply line and the drainage line are respectively arranged substantially side by side and together form the probe shaft of the micro-dialysis probe.

Abstract: A micro-dialysis probe extending longitudinally between a proximal probe opening and a distal probe tip and having a supply line and a drainage line for a drip-feed solution. A tube may be provided for supporting the drainage line. A dialysis section, wherein the flow channel for the drip-feed solution experiences an inversion, is formed generally between the supply line and the drainage line, in the vicinity of the distal probe tip. The supply line and the drainage line are arranged substantially side by side and together form the probe shaft of the micro-dialysis probe.

Abstract: A method and apparatus for determining solute levels by affinity viscosimetry involving a sensitive fluid, in which the sensitive fluid flows continuously through a first hydraulic resistor in the flow direction of the dialysis chamber, and the sensitive fluid modified by dialysis simultaneously flows through another resistor, wherein the pressure differences between the resistors is determined on-line with the aid of pressure sensors and converted into a relative value which is approximately proportional to the concentration of solute.

Abstract: This invention relates to an automatic sample collector for liquids which are discharged from a chromatographic column, a dialysis apparatus, or a reaction container, for example, and are consecutively collected at a give volume division, a method for collecting samples of a liquid in a predefined chronological sequence, and uses of the inventive sample collector. The volume is divided by assigning one or several gas-permeable liquid barriers (4, 5) to each collection container (3). The sample collector can be produced as one piece which is for single use and is made of polypropylene, Teflon, or other suitable materials. The inventive sample collector has the advantage that it requires no source of energy and can be autoclaved and miniaturized, among other things. The design of the inventive sample collector makes it possible to keep the content of the collection containers free from oxygen or immediately freeze the liquid flowing into the collection containers.