Microstructured Materials for Cell Analysis and Regeneration
Written by Aditi Risbud
On Thursday evening, Dino Di Carlo of the University of California, Los Angeles presented his work on using microfluidics to manufacture three-dimensional microstructured materials. Di Carlo’s research leverages microstructures to enable function in biology at the cellular scale.
The first strategy Di Carlo discussed was structuring magnetic materials to manipulate magnetically-labeled cells by amplifying magnetic field gradients. In particular, applying large forces on cells to initiate signaling is challenging because the “force envelope” diminishes as the particle size decreases.
Using a technique called magnetic ratching cytometry, researchers can leverage structured ferromagnetic materials at the microscale to generate effects at the nanoscale. In particular, changing the pitch between arrays of micromagnets allows the researchers to sort cells in their equilibrium configuration by magnetic content. This separation based on relative expression level or relative volume is useful in applications such as detecting cancer cells.
The next strategy is using microfluidically-created particles that flow into a wound and anneal together to form a microstructured scaffold with porosity that allows tissue integration. This technique addresses the “foreign body response” caused by traditional implants that limits transport of nutrients and interferes with drug delivery.
To heal or augment function, Di Carlo says, the tissue must integrate seamlessly in situ. Using microporous annealed particle (MAP) gels, a slurry of particles is introduced into a wound or blood to vessel. These gels are then annealed to form a scaffold network connected to the surrounding tissue, with the negative “void space” creating porosity. This microstructured technique leads to accelerated healing of wounds.
Lastly, Di Carlo’s group can structure particles themselves in three dimensions to enable emergent physical properties. They used a technique called optical transient liquid molding, which employs two-dimensional light patterns to create three-dimensional structures, a so-called “extrusion of an extrusion.”
Di Carlo and his colleagues have also developed freely available software, called uFlow, to enable automated three-dimensional structural design of materials such as shaped fibers, “Janus” fibers, or chemically heterogeneous fibers.
Di Carlo said receiving the Outstanding Young Investigator Award is “particularly an honor because I’m relatively new to the materials field.”