Kerry defended her Ph.D. in Chemistry in Aug 2018, after which she joined Gelest Inc. in Philadelphia. In her Ph.D. work, she created polymer capsules with ‘emergent‘ properties as a result of internal chemical reactions. Her paper on inflating and exploding capsules was recently published in Langmuir.
The architecture of life is based on cells (microscale containers), which have organelles, i.e., smaller containers inside them. We are trying to mimic this by creating microscale capsules that have smaller capsules inside them. These multicompartment capsules (MCCs) can contain nanoparticles, enzymes, or bacteria in specific inner compartments (see paper in Chemical Science, 2017). We are collaborating with Prof. Bill Bentley (BioE) in this research.
Stopping blood loss from wounds is crucial during surgeries and on the battlefield. We got into this area when we discovered a ‘hemostatic’ polymer that is able to convert liquid blood into a gel (see above) by a self-assembly mechanism. The same polymer rapidly arrests bleeding from severe injuries in animal models. This technology won the Invention of the Year award at UMD in 2009, and since then has been patented and FDA-approved. Gel-e, Inc., a company run by a former student, is bringing this to the market.
3. A. Gargava, S. Ahn, W. E. Bentley, S. R. Raghavan
6. S. Gharazi, B. C. Zarket, K. C. DeMella, S. R. Raghavan
This paper shows how to endow a capsule with a ‘hermetic’ seal, i.e., one that is perfectly leak-proof. This is done by making the capsule shell out of a wax with a defined melting temperature. Above this temperature, the shell melts and the contents are released in a burst. The ability to hold on to contents for long times and then release them on-demand makes these capsules useful in a variety of applications.
Gels that absorb a lot of water are used in many products, such as diapers. This paper described a new superabsorbent gel that beat the world record for water-absorption – it could absorb 3000 times its weight in water. The gel could be easily made in the lab and it was also mechanically strong. Since this paper was published, our recipe has been used by numerous researchers around the world.
Making gels by 3D printing requires an expensive ‘printer’ and special UV-sensitive ‘inks’. This paper shows an alternative way to create 3D gels of the biopolymer alginate. The key is to induce gelation by an electric field, i.e., by a process called ‘electroformation’. It can be easily done in any lab at low cost, and it yields robust gels in precise shapes and patterns. Living cells can be readily embedded in these gels.
This paper reported the first example of a nanoparticle-based fluid whose viscosity could be significantly transformed by shining light. The fluid was initially a flowing suspension (sol) of clay nanoparticles. When subjected to UV light, molecules in the sol became photolyzed to form acid. The acid induced the nanoparticles to form a 3-D network, and thereby the sol turned into a gel.