The disclosure relates to a microfluidic system for the screening of polymorphs, morphology, and crystallization kinetics under well-mixed, continuous-flow at controlled supersaturations. The disclosure also relates to a method for screening crystalline polymorphs and morphology, and crystallization kinetics. The microfluidic system includes a microfluidic chamber having one or more inlets, a passive mixing zone, and a trap zone. The passive mixing zone promotes mixing of solvent, solute, and optionally antisolvent under stable, controlled levels of supersaturation. The trap zone similarly has stable, controlled levels of supersaturation and correspondingly low velocity to retain solute crystals formed in the trap zone for time-dependent evaluation.

A method of preparing a bioprocess solution includes producing a mixture of liquid and air by hydrating a powder separating the liquid from the air by providing the mixture to a first filter capsule and allowing the liquid to flow to an outlet across a hydrophilic membrane of the first filter capsule while directing the air upwards along the first filter capsule toward a second filter capsule arranged above the first filter capsule, and venting the air from the second filter capsule by allowing the air to flow through a hydrophobic membrane of the second filter capsule.