Abstract: A method is disclosed for calibrating a sensor element, which has an immobilized probe oligonucleotide, via which the bonding of a target nucleic acid (Z) can be detected by the sensor. In at least one embodiment, the method includes: a) bringing the sensor element into contact with a control nucleic acid (K), the melting temperature Tm(K) of which is less than the melting temperature Tm(Z) of the target nucleic acid (Z); b) hybridizing the control nucleic acid (K) to the probe oligonucleotide at a temperature T[p]<Tm(K), and detecting a positive control signal; and optionally c) modifying the stringent conditions such that T[n]>Tm(K) and detecting a negative control signal at a temperature T[n]. According to a refinement of at least one embodiment of the invention, a measuring signal of the target nucleic acid (Z) is measured at a measuring temperature T [mess], where Tm(K)<T[mess]<Tm(Z). The method is suited in particular for the calibration and quality control of microarrays.

Abstract: A process is disclosed for detecting cells in a liquid sample, which includes: i) filtration of the liquid sample through a porous membrane which is suitable for retaining detectable cells, where at least one subregion of a support is configured as transparent supporting body and the membrane is arranged over its area on the transparent supporting body in such a way that detectable cells are retained on at least part of the surface of the membrane and that at least part of the sample liquid passes through the membrane, ii) application of a liquid optical medium which has essentially the same refractive index as the supporting body, and iii) optical measurement of at least a subarea of the membrane in order to detect detectable cells.

Abstract: An array of valves are arranged in n columns and m lines and which are each designed to control a fluid flow in an associated flow channel in a lab-on-a-chip system. The array includes at least two valves, every column having not more than one valve and every line having from zero to n valves. A device is used for actuating the valves. The valves are pressure-actuated. To produce the device, the flow channels are arranged in accordance with the arrangement of the valves. Which valves are actuated being changeable by movement of projections relative to array of valves so as to change which valves the projections are pressed against.

Abstract: An array of valves are arranged in n columns and m lines and which are each designed to control a fluid flow in an associated flow channel in a lab-on-a-chip system. The array includes at least two valves, every column having not more than one valve and every line having from zero to n valves. A device is used for actuating the valves. The valves are pressure-actuated. To produce the device, the flow channels are arranged in accordance with the arrangement of the valves. Which valves are actuated being changeable by movement of projections relative to array of valves so as to change which valves the projections are pressed against.

Abstract: An array of valves are arranged in n columns and m lines and which are each designed to control a fluid flow in an associated flow channel in a lab-on-a-chip system. The array includes at least two valves, every column having not more than one valve and every line having from zero to n valves. A device is used for actuating the valves. The valves are pressure-actuated. To produce the device, the flow channels are arranged in accordance with the arrangement of the valves.

Abstract: A substrate of a lab-on-a-chip system has two adjacent recesses, one serving as a flow channel and the other one being filled with an elastomer compound. In a first state, the elastomer compound and the substrate delimit the flow channel in a section. In a second state, the elastomer compound takes up the space in the recess in the substrate along a cross-section of the flow channel, thereby completely closing the flow channel. The substrate and the elastomer compound may be produced by injection molding techniques.

Abstract: A method for identification and quantification of at least one single-stranded target nucleic acid and a kit for detection of at least one single-stranded target nucleic acid in a sample are described. The method includes contacting at least one solid carrier that includes at least one capture oligonucleotide immobilized thereon with at least one complementary-strand oligonucleotide, at least one single-stranded target nucleic acid, and at least one reporter oligonucleotide that includes a label. The target nucleic acid is identified by reading the label of the reporter oligonucleotide on the carrier.

Abstract: An assembly and a method for filtration are disclosured, which are suitable in particular for the filtration of cells, for example tumor cells, from a sample, for example a blood sample. In the method, a pressure differential between the pressure upstream and the pressure downstream of a filter is determined; and the pressure differential between upstream and downstream of the filter is adjusted such that the pressure differential does not exceed a predetermined value.

Abstract: An embodiment relates to a method and to an array for detecting live circulating or disseminated cells in body fluids (for example blood, urine) or tissue samples (for example bone marrow) mixed with liquid. The method includes: a) filtering the liquid sample through a porous membrane that is suitable for retaining cells to be detected, such that cells to be detected come to rest upon at least a part of the surface of the membrane and the sample liquid passes the membrane; b) applying a first process liquid containing a first agent for marking the cells to be detected with a first marker; c) incubating the process liquid on the membrane for a predetermined time period, wherein the cells to be detected are marked; and d) detecting the marked cells to be detected on the surface of the membrane.

Abstract: A process is disclosed for detecting cells in a liquid sample, which includes: i) filtration of the liquid sample through a porous membrane which is suitable for retaining detectable cells, where at least one subregion of a support is configured as transparent supporting body and the membrane is arranged over its area on the transparent supporting body in such a way that detectable cells are retained on at least part of the surface of the membrane and that at least part of the sample liquid passes through the membrane, ii) application of a liquid optical medium which has essentially the same refractive index as the supporting body, and iii) optical measurement of at least a subarea of the membrane in order to detect detectable cells.

Abstract: An assembly and method are disclosed for the filtration of a liquid and the use thereof, wherein a supporting body is designed in a recess of a carrier and a filter membrane lies flat on the supporting body. The filter membrane and the supporting body are designed to be permeable to liquids and thus serve as filters, in particular for filtering tumor cells from blood. The carrier can having standard shapes of an object carrier for microscopy and the filtration residue on the filter membrane can be easily handled and examined in the microscope. As a result of the filter membrane lying level on the supporting body, the filtration residue can be particularly well examined microscopically.

Abstract: A substrate of a lab-on-a-chip system has two adjacent recesses, one serving as a flow channel and the other one being filled with an elastomer compound. In a first state, the elastomer compound and the substrate delimit the flow channel in a section. In a second state, the elastomer compound takes up the space in the recess in the substrate along a cross-section of the flow channel, thereby completely closing the flow channel. The substrate and the elastomer compound may be produced by injection molding techniques.

Abstract: An array of valves are arranged in n columns and m lines and which are each designed to control a fluid flow in an associated flow channel in a lab-on-a-chip system. The array includes at least two valves, every column having not more than one valve and every line having from zero to n valves. A device is used for actuating the valves. The valves are pressure-actuated. To produce the device, the flow channels are arranged in accordance with the arrangement of the valves.

Abstract: A method is disclosed for calibrating a sensor element, which has an immobilized probe oligonucleotide, via which the bonding of a target nucleic acid (Z) can be detected by the sensor. In at least one embodiment, the method includes: a) bringing the sensor element into contact with a control nucleic acid (K), the melting temperature Tm(K) of which is less than the melting temperature Tm(Z) of the target nucleic acid (Z); b) hybridizing the control nucleic acid (K) to the probe oligonucleotide at a temperature T[p]<Tm(K), and detecting a positive control signal; and optionally c) modifying the stringent conditions such that T[n]>Tm(K) and detecting a negative control signal at a temperature T[n]. According to a refinement of at least one embodiment of the invention, a measuring signal of the target nucleic acid (Z) is measured at a measuring temperature T [mess], where Tm(K)<T[mess]<Tm(Z). The method is suited in particular for the calibration and quality control of microarrays.