Recently, polymeric micelles self-assembled from amphiphilic polymers have been studied for various industrial and biomedical applications. This nanoparticle self-assembly typically occurs in a solvent-exchange process. In this process, the quality of the resulting particles is uncontrollably mediated by polymeric solubility and mixing conditions. Here, we hypothesized that improving the solubility of an amphiphilic polymer in an organic solvent via chemical modification while controlling the mixing rate of organic and aqueous phases would enhance control over particle morphology and size. We examined this hypothesis by synthesizing a poly(2-hydroxyethyl)aspartamide (PHEA) grafted with controlled numbers of octadecyl (C18) chains and oligovaline groups (termed “oligovaline-PHEA-C18”). The mixing rate of DMF and water was controlled either by microfluidic mixing of laminar DMF and water flows or through turbulent bulk mixing. Interestingly, oligovaline-PHEA-C18exhibited an increased solubility in DMF compared with PHEA-C18, as demonstrated by an increase of mixing energy. In addition, increasing the mixing rate between water and DMF using the microfluidic mixer resulted in a decrease of the diameter of the resulting polymeric micelles, as compared with the particles formed from a bulk mixing process. Overall, these findings will expand the parameter space available to control particle self-assembly while also serving to improve existing nanoparticle processing techniques.
Nicholas E. Clay,a Joseph J. Whittenberg,a Jiayu Leong,a Vivek Kumar,a Jinrong Chen,a Insil Choi,b Evangelos Liamas,c Jeremy M. Schieferstein,a Jae Hyun Jeong,ab Dong Hyun Kim,d Zhenyu Jason Zhang,c Paul J. A. Kenis,ae Il Won Kimb and Hyunjoon Kong*ae
* Corresponding authors
a Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, 61801 USA
b Department of Chemical Engineering, Soongsil University, 369 Sangdo-ro, Dongjak-gu, Seoul 06978, Republic of Korea
c School of Chemical Engineering, University of Birmingham, Egbaston, Birmingham, UK
d Department of Human and Culture Convergence Technology R&BD Group, Korea Institute of Industrial Technology, Ansan-si Gyeonggi-do 426-910, Republic of Korea
e Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, 61801 USA