Abstract: A method comprises providing a microfluidic device including a reservoir; an injection nozzle at the bottom of the reservoir, the injection nozzle being wider at its top than at its bottom; an injection channel below the injection nozzle; and a microfluidic channel below the injection channel. The method further comprises placing fluid in the reservoir, and allowing the fluid to passively flow through the injection nozzle and the injection channel.

Abstract: In one implementation, a microfluidic probe has a non-planar processing surface and an inlet aperture. The shape of the surface may be selected to produce a specific velocity gradient profile across a surface onto which fluid is deposited using the microfluidic probe, for example a constant velocity gradient or a velocity gradient that decreases linearly with distance from the inlet aperture. The microfluidic probe may define and overflow notch in a perimeter edge of the processing surface.

Abstract: A microfluidic probe head is provided. The microfluidic probe head comprises a processing surface. The processing surface has a first and second aperture and a fluid injection channel, which leads to the first aperture. The microfluidic probe head comprises also a first fluid aspiration channel which leads to the second aperture. Thereby, the second aperture forms a slot in the processing surface. Furthermore, a microfluidic probe may be provided comprising the microfluidic probe head.

Abstract: A microtiter plate comprising a first array of M×N wells and a microfluidic probe insert is provided. The microfluidic probe insert includes a second array of M×N microfluidic probe conduits, forming N columns of M conduits. The M conduits include respective orifices in a bounding plane and extend, each, perpendicularly to the bounding plane on one side. The microfluidic probe insert also includes N vacuum circuits, each comprising at least one vacuum port and M openings in the bounding plane, where 2?M, 2?N. The microfluidic probe insert is positioned on the microtiter plate and the microfluidic probe conduits are inserted in respective wells. A processing liquid is ejected from M conduits via the M orifices of the M conduits by applying a negative pressure to a corresponding set of N vacuum circuits via the respective one or more vacuum ports.

Abstract: A method for manufacturing a fluidic device is provided. The method comprises providing a capillary, providing a structure having a fluidic channel and an opening, reducing an outer diameter of a portion of the capillary to be smaller than the opening of the structure. Furthermore, the method comprises inserting, at least partly, the portion of the capillary through the opening of the structure into the fluidic channel and applying heat to the structure to expand the inserted portion of the capillary to fit the capillary to the structure.

Abstract: A method for manufacturing a fluidic device is provided. The method comprises providing a capillary, providing a structure having a fluidic channel and an opening, reducing an outer diameter of a portion of the capillary to be smaller than the opening of the structure. Furthermore, the method comprises inserting, at least partly, the portion of the capillary through the opening of the structure into the fluidic channel and applying heat to the structure to expand the inserted portion of the capillary to fit the capillary to the structure.

Abstract: A microfluidic probe head is provided. The microfluidic probe head comprises a processing surface. The processing surface has a first and second aperture and a fluid injection channel, which leads to the first aperture. The microfluidic probe head comprises also a first fluid aspiration channel which leads to the second aperture. Thereby, the second aperture forms a slot in the processing surface. Furthermore, a microfluidic probe may be provided comprising the microfluidic probe head.

Abstract: A microfluidic device may be provided. The microfluidic device comprises a processing surface having an aperture. The microfluidic device comprises a liquid ejection channel. The liquid ejection channel guides to the aperture. The microfluidic device comprises a first liquid injection channel guiding to the liquid ejection channel. The first liquid injection channel has a first end and a second end and is arranged to provide a fluid flow from the first end to the second end. At least a portion of the first liquid injection channel is closer to the processing surface than (both) the first and second ends to sediment particles.