(6cb) Combining Colloidal Chemistry and Microfluidics

Authors: 
Shah, R. K., Harvard University


Poly(N-isopropylacrylamide) or PNIPAM microgels are polymeric particles consisting of cross-linked three dimensional networks. They swell and shrink significantly by absorbing and expelling large quantities of water and this property makes them extremely valuable for a number of applications including macromolecular delivery, sensors, chemical separations, etc. This poster will describe the synthesis and characterization of novel structures formed by the directed assembly of colloidal PNIPAM microgels in droplets. Two specific structures designed: (i) microgel vesicles, i.e., colloidosomes made out of microgels and (ii) gelospheres, i.e., cross-linked spherical particles formed by aggregation of microgels in droplets. We employ microfluidic techniques to disperse aqueous suspensions of microgels in oil. The use of these techniques allows the formation of monodisperse emulsions and, thus, monodisperse self-assembled structures. Such structures can be of immense use for sequestering macromolecules and releasing them in a controlled way in numerous applications.