In the present work, a workflow on the development of a continuous protein crystallisation is introduced, with lysozyme as a model protein, from micro L screening experiments, to small scale batch crystallisation experiments in a shaking crystallisation platform, and to batch and continuous crystallisation experiments in an oscillatory flow platform. The lysozyme crystallisation investigated were for a concentration range from 30 to 100 mg/mL, shaking conditions from 100 to 200 rpm in the batch shaking crystallisation platform, and oscillatory conditions with amplitude ( 0 ) from 5 to 30 mm and frequency ( ) from 0.1 to 1.0 Hz in the batch oscillatory flow crystallisation platform. We propose the use of the Reynold's number ( ) for scaling up of the process from the shaking batch to the continuous oscillatory flow platform. Additionally, it is shown that the nucleation rate increased with increase in concentration of initial lysozyme solution, or increase in shear rate, inducing smaller size of lysozyme crystals. These indicate that continuous crystallisation platforms may offer advantages to the downstream bioprocessing of proteins.

In this work, we designed and built a continuous crystallisation oscillatory flow platform. The lysozyme crystallisation behaviours were investigated at concentrations from 30 to 100 mg/mL, under oscillatory conditions with amplitude (0) from 10 to 25 mm and frequency () from 0.05 to 0.25 Hz in a batch oscillatory flow crystallisation platform. The nucleation rate increased with increase in concentration of initial lysozyme solution, and was also found to increase with increase in shear rate. By learning the thermodynamics and kinetics of lysozyme crystallisation in batch oscillatory flow, the batch crystallisation process was successfully transferred to a continuous oscillatory flow crystallisation process. The equilibrium state of continuous crystallisation reached at residence time 200 min, and the final product crystals shape and size were consistent during the continuous process. This work demonstrates the feasibility of oscillatory flow based platforms for the development of continuous protein crystallisation as for downstream bioseparation.