|Project Title||Non-Spherical Bio-Imaging Particles|
Non-spherical particles are beneficial for drug delivery, bioimaging and biometrics due to their large surface area. Currently, the dominant shape of polymer particles has been spherical because of the difficulty of manufacturing large quantities of monodispersed particles with tunable shapes and sizes. This patented process controls the shape and assembly of polymer droplets within a flow-focusing droplet microfluidic device to form non-spherical particles and chains. The method relies on water-based magnetic liquid (ferrofluid) as a continuous phase to (1) induce droplet formation (2) controllably change the shape of droplets, and (3) assemble droplets into chains. These ferrofluids induce magnetic dipole movement within the droplets, making it possible for the droplets to deform to non-spherical shapes and assemble into chains of tunable lengths.
Placing the polymers in a ferrofluid allows for manipulation of their shape, as well as creating tunable length chains. When an external magnetic field gradient is applied, the non-magnetic polymer droplets inside ferrofluids experience both magnetic and hydrodynamic drag forces. This force can be used to stretch the spherical shape of droplets into ellipsoids of different sizes. Other shapes are also possible with different designs of magnetic field patterns. The ferrofluids also promote dipole-dipole interactions, leading to the assembly of linear chains with tunable lengths oriented along the magnetic field direction. This process can produce non-spherical droplets at up to 1000 per second.
US Patent No. 8,721,936
Leidong Mao, Associate Professor, UGA College of Engineering
Jason Locklin, Associate Professor, UGA Department of Chemistry
Taotao Zhu, UGA College of Engineering
|Posted Date||Jul 21, 2017 2:13 PM|