Abstract: Microwells, which are open on both sides and are arranged two-dimensionally in a microwell matrix (4), are hermetically closed by pressure on both sides using plugs (6) covered with a sealing sheet (11). A layer of elastic material (9), which is arranged between the plug (6) and the sealing sheet (11), guarantees uniform pressure on all the microwells of a microwell matrix (4) which is loosely held by a frame structure (1). Continuous peripheral elevations (2), which protrude in both directions at right angles to the plane of the microwell matrix (4), ensure that the deformable thin layer of elastic material (9) does not escape sideways between the plug (6) and the microwell matrix (4) during the pressing process. A plurality of microwell matrices (4) are held simultaneously by the frame structure (1) and are hermetically closed by a corresponding number of allocated plugs (6), which are fastened to a base plate (7) and a cover plate (8), respectively.

Abstract: Microwells, which are open on both sides and are arranged two-dimensionally in a microwell matrix (4), are hermetically closed by pressure on both sides using plugs (6) covered with a sealing sheet (11). A layer of elastic material (9), which is arranged between the plug (6) and the sealing sheet (11), guarantees uniform pressure on all the microwells of a microwell matrix (4) which is loosely held by a frame structure (1). Continuous peripheral elevations (2), which protrude in both directions at right angles to the plane of the microwell matrix (4), ensure that the deformable thin layer of elastic material (9) does not escape sideways between the plug (6) and the microwell matrix (4) during the pressing process. A plurality of microwell matrices (4) are held simultaneously by the frame structure (1) and are hermetically closed by a corresponding number of allocated plugs (6), which are fastened to a base plate (7) and a cover plate (8), respectively.

Abstract: When chemical substances are pipetted in individual microwells of a microwell array (4), problematic evaporation effects arise concerning the solvent with which the microwells are already filled. In order to prevent such undesired evaporation effects, a pipetting device for the automated pipetting of chemical substances having a holder (3), which receives at least one microwell array (4), and a pipetting head (11), which is fitted in such a way that it can be moved, is designed with the pipetting head (11) being fastened, by means of a holding device, to a plate (7) which follows the movements of the pipetting head (11) during the pipetting process. The plate (7) forms above the microwell array (4), in conjunction with a frame (5) tightly enclosing the microwell array (4), a sealed gas space (14) into which the pipetting head (11) protrudes through a matched hole (13) in the plate (7).