Microfluidic Assembly of Quantum Dot Micelles

The controlled self-assembly of polymer-stabilized CdS quantum dot nanoparticles into quantum dot compound micelles (QDCMs) using microfluidics is demonstrated. In a flow-focusing configuration, water is introduced to a blend solution of block copolymer-stabilized quantum dots with amphiphilic block copolymer stabilizing chains. QDCM assembly via initial phase separation and subsequent agglomeration continue until a downstream quench step. Control over mean particle size and size distribution characteristics is demonstrated via both inlet concentrations and flow rate. The QDCMs assembled through this method are stable in aqueous solutions, and show internal and external structure in keeping with previous assembly methods. The on-chip evolution of QDCM formation and growth is resolved through fluorescence scattering. Particle size distributions and associated statistics are determined through off-chip analysis.