Abstract: The present invention relates to a device for use in a cartridge (9), a cartridge, a use of a device in a cartridge and a system for preparing a liquid solution for a medical procedure. The device comprises a hollow body (24) defined by a wall (50) enclosing a cavity space of the body. The body (24) has a first end (52) and a second end (53), and is provided with a least one slit-shaped opening (55) extending through the wall. The first end is open and adapted for receiving liquid to be introduced into the cartridge. The liquid leaves the device through the slit-shaped opening in a flow direction. The slit-shaped opening has a first extension and a second extension substantially perpendicular to the flow direction and to the first extension. The second extension is significantly shorter than the first extension.

Abstract: The invention refers to a filter (23, 24) a cartridge (9) containing a particulate material (20), a use of the filter and a system for preparing a liquid solution. The cartridge (9) includes an inner space (10) for housing the particulate material (20), an inlet (21) arranged to permit the introduction of a liquid into the inner space, and an outlet (22) arranged to permit discharge of liquid from the inner space. The filter (23) is arranged at the outlet (22) to permit passage of the liquid in a filter direction (x) through the filter but to prevent passage of the particulate material through the filter. The filter includes at least one slit-shaped opening, which has a first extension and a second extension being substantially perpendicular to the filter direction (x). The second extension is significantly shorter than the first extension.