Microfluidic Chip

Abstract

The invention relates to a microfluidic chip for biological, chemical and medical analysis. Cavities and channels, which connect these cavities to one another and which transport, based on the capillary effect, liquids required for carrying out analysis and synthesis, are arranged inside the microfluidic chip. At least one of the cavities is a reaction chamber. The microfluidic chip is characterized by having a layered construction made of light-curing hydrophilic plastic material based on a 3-D layer model and by having a covering layer made of a hydrophobic material. In the layered body made of hydrophilic material, channels that come from different cavities and do not intersect lead to the at least one reaction chamber.

Description

In the attached drawing, a microfluidic chip is shown in a detail and in a greatly enlarged representation, but the cover layer has been left out.

The chip has a central cavity 1, which is surrounded by a ring-shaped cavity 2 and separated from the latter by the wall 3. The ring-shaped cavity 2 has openings 4 disposed in star shape, which are separated from one another by crosspieces 5.

Channels 6 rise from the bottom of the central cavity 1, in vertical manner, which channels are guided up to a further cavity 7 by way of the crosspieces 5. The cavity 7 is a reaction chamber, for example.

In this chamber, a fluid that has been passed in from the central cavity 1 by way of the channels 6 reacts with an analysis fluid, for example, which is passed in from the ring-shaped cavity 2 by way of channels 8. The channel 8 rises upward from the bottom of the ring-shaped cavity 2, in the wall of this cavity, and is then passed to the cavity 7 by the channel 6, without any intersection.

The transport of the fluids comes about by means of the capillary effect of the hydrophilic material of which the microfluidic chip consists. In this connection, it is essential, for one thing, that the cover material, not shown, is configured to be hydrophobic, and, for another thing, that the edges of the channels are configured to be extremely precise at the locations of the transition from the vertical to the horizontal. This relates, for one thing, to the edges at which the vertically rising channels 6 and 8 lead out of the cavities 1 and 2, in each instance, to the chip surface, and to the edges at which these vertically rising channels meet the bottom of the cavity, in each instance. At these locations, the channels are guided back into the wall a piece, and form an acute angle with the bottom surface here.

Such chips are filled with an analysis fluid, for example, in the ring space 2, by the manufacturer. For an examination, the material to be examined, for example blood or components of blood, is filled into the central cavity 1 by means of a pipette or syringe, through the cover layer not shown here. On the basis of the capillary forces, the two fluids then get into the chamber 7. Statements about the substance to be examined can be made on the basis of the reaction that takes place there.

Claims

1. Microfluidic chip for biological, chemical, and medical analysis, in which cavities and channels that connect the former with one another, which channels transport fluids required for the analysis, on the basis of the capillary effect, are disposed, whereby at least one of these cavities is a reaction chamber comprising a layered construction of light-curing hydrophilic plastic material, on the basis of a 3D layer model, and a cover layer made of a hydrophobic material, whereby channels (6, 8) that come out of different cavities (1, 2), and run without intersections in the layer body structured from hydrophilic material empty into the at least one reaction chamber (7).

2. Microfluidic chip according to claim 1, wherein a central cavity (1) covered by the hydrophobic layer is generated in the chip, which cavity is surrounded by a cavity (2) configured in ring shape, which also has openings (4) covered by the hydrophobic layer, separated from one another by means of crosspieces (5), from which openings one channel (8), in each instance, leads to a reaction chamber (7) assigned to the opening, which reaction chamber is disposed around the central cavity (1) and around the ring cavity (4), with other reaction chambers, in star shape, while channels (6) that are placed in the surface of the crosspieces (5), bridging the ring cavity (2), lead from the central cavity (1) to the assigned reaction chamber (7), in each instance, whereby the channels (6, 8) that proceed from the ring cavity (2) as well as from the central cavity (1) make a transition into grooves that are open towards the interior of the cavities (1, 2) and rise in the walls of the cavities (1, 2), in perpendicular manner.

3. Microfluidic chip according to claim 2, wherein the channels (6, 8) that are disposed vertically in the walls form an acute angle with the bottom surface at their cavity-bottom-side end.

4. Method for the production of a cover layer for a microfluidic chip according to claim 1, wherein first, a film of one or more layers of light-curing plastic material is generated, whereby the final layer is only partially polymerized, after which the film formed in this manner is laid onto the microfluidic chip generated previously, with the partially polymerized layer, and the layer that was only partially polymerized up to that time is polymerized through, so that the chip is given a monolithic structure.

5. Method according to claim 4, wherein the film is continuously produced between at least one pair of rollers, whereby the light-curing material is disposed between the two rollers, one of which has the exposure device that serves for curing, and the cover layer produced in this manner is laid onto the microfluidic chips that are produced in large numbers, and polymerized through, also using a continuous method.