Massachusetts Institute of Technology │ Cambridge, Massachusetts
For innovative methods to create novel materials one molecular layer at a time, and for applying these materials to areas ranging from drug delivery to energy storage.
Some of the most complex and important structures in our world come in thin layers of exquisitely intricate composition and dimensions, only a few molecules in thickness. Many are natural, such as tissues and membranes in our bodies and other organisms, but many are designed and created by humans for various purposes. They can be used for everything from semiconductors, LEDs, solar cells, and batteries to medical devices and drug delivery systems, making their design and fabrication enormously important. Paula Hammond is one of the most creative scientists working in this field, blending biology and chemical engineering to pioneer complex molecules and composite materials with nanoscale engineering approaches.
Engineers have developed various techniques for the fabrication of thin films, but one of the most common and efficient is known as layer-by-layer (LbL) deposition. In this method, alternating positively and negatively charged molecular layers are built up one by one, held together mostly by electrostatic forces. Depending on the ultimate function desired for the thin film, the technique can be modified and tweaked in various ways, using different materials to self-assemble with nanoscale precision and control—a scale 100,000 smaller than the thickness of a sheet of paper. Achieving that precision and control, however, requires vast knowledge of the forces in play, and this is where Hammond’s work has focused. She has developed ways to perform LbL not only in two dimensions, meaning layer by layer in one axis, but in three dimensions, allowing greater variations and customization in thin film assembly. She has extended this research into the development of responsive layers, which are films that can actually change their behavior according to different environmental conditions such as temperature, light, pH, and magnetism. Her work on this technology provides a roadmap to its use in thin-film battery systems, fuel cells, and solar cells.
Over the past several years, Hammond has turned her focus towards medical applications. Layered coatings target nanoparticles to deliver drugs to specific areas, such as tumors, circumventing the body’s protective immune system and carrying a therapeutic payload such as RNA or proteins to precisely where it’s needed. Other nanosystems can be used for the staged release of vaccines. Organic films can be used to provide scaffolding structures for wound healing and bone regeneration. As a co-founder of MIT’s Institute for Soldier Nanotechnology, she invented a layered dressing that causes almost instantaneous blood clotting, which can be used to save lives and limbs on the battlefield. Now she has a particular focus on difficult to treat cancers, including brain and ovarian cancer.
Hammond’s favorite teacher in high school in Detroit first kindled her passion and curiosity for chemistry, a fascination she followed to become a chemical engineering major at MIT after graduation. She worked in industry as an engineer for two years before returning to continue her graduate studies at the Georgia Institute of Technology while working at the Georgia Tech Research Institute, and went on to earn her doctorate at MIT. She was an NSF postdoctoral fellow at Harvard before returning to MIT, where she has continued her career ever since.
Hammond’s accomplishments as an educator and administrator match her scientific contributions. She began as an assistant professor at MIT in 1995 and rose to become the first woman and the first black professor to become Head of the Department of Chemical Engineering. Along the way, she has mentored more than a hundred graduate students and post-doctorate fellows, and continues to lead her research group at MIT.
Building upon her creativity in devising versatile and diverse applications for layer-by-layer techniques, Hammond co-founded the biotechnology company LayerBio, Inc. in 2013, which marketed her LayerForm technology for regenerative medicine and drug delivery applications. She is also a board member and advisor of several companies including Moderna and Alector, and in 2021 was selected as a member of the President’s Council of Advisors on Science and Technology. She holds 20 patents arising from her research.
Hammond’s range of honors highlights her versatility and interdisciplinary gifts. She is one of the elite group to be elected as a fellow of all three national academies: the National Academy of Sciences, National Academy of Engineering, and National Academy of Medicine. She is also a fellow of American Academy of Arts and Sciences and the National Academy of Inventors. Perhaps her most unusual accolade, however, is that she may be the only chemical engineer honored with her own LEGO figure, created by internationally known science writer and LEGO designer Maia Weinstock.
Paula Hammond is a world leader in the fields of polymer chemistry and nanotechnology, particularly in finding ingenious ways to bridge the gap between the elegant theories of the laboratory and their practical application in the real worlds of materials science, medicine, electronics, and energy. She is a true innovator whose influence ranges far beyond the confines of the lab or classroom into corners of the world that touch almost all of us.