Abstract:

A self-dispensing and osmosis-based microfluidic crystallization device was reported. This device automatically dispenses droplets containing protein and precipitant into an array of crystallization chambers by pre-degassing, and then gradually concentrates these droplets at different rates by osmotic dewatering through a polydimethylsiboxane(PDMS) membrane using a row of integrated dialysis channels filled with different concentration of salt solution. This concentration process drives the protein/precipitant mixture into supersaturated, thus tending toward the crystallization state. This device allows for screening a wide range of supersaturation in one trial for rapid optimization of protein crystallization. The feasibility of this crystallization device is demonstrated using the model proteins of lysozyme.

Key words: Self-dispensing, High-throughout screening, Osmotic dewatering, Protein crystallization