Microfluidic-assisted polymer-protein assembly to fabricate homogeneous functionalnanoparticles

Functional polymer-protein nanoparticles (NPs) have broad applications in biotechnology and nanotechnology. In principle, controllable and vigorous mixing is required to fabricate homogeneous NPs, which remains a challenge via conventional bulk synthetic methods. In this study, an electrokinetics (EK) based microfluidic reactor with fast mixing is explored to assemble functional proteins with polymers in an ethanol/water co-solvent system. The resultant NPs show significantly improved size distribution by comparison with the ones prepared using conventional bulk method, while the NPs size can be tuned by adjusting the mass ratio of polymer to protein. The functionalities of the assembled proteins are sustained upon the EK based microfluidic mixing, indicating the application potential of our method in the controlled assembly of different functional proteins.