Device and a method for promoting crystallisation

A microfluidic device for promoting crystallization of target molecules, said device comprises a solid structure with a first face and an opposite second face and with a plurality of liquid channels,

• each of said liquid channels comprises a target molecule solution inlet and a precipitant inlet, each of the target molecule solution inlets being in liquid communication with a respective one of said precipitant inlets through a respective one of the liquid channels,
• each of said liquid channels comprises a crystallization channel section adjacent to a respective one of the precipitant inlets,
• each of said crystallization channel sections has a capillary stop arranged in or adjacent to the respective precipitant inlet,
• said microfluidic device comprises at least a first part having a first face and a groove face with a plurality of grooves for forming said crystallization channel sections and a plurality of removable lids which by tearing can be individually removed to expose at least a part of the crystallization channel sections for harvesting crystallized macromolecules,
• each of said lids having a second face and a groove face, wherein each of said removable lids is applied above and sealed along one or more of said grooves to said crystallization channel sections of the liquid channels.