Ronit Freeman uses nature’s building blocks to create innovative technologies, from synthetic cells to treatments that could transform health care.
“Let me show you an example.”
Ronit Freeman stops mid-interview to have her research operations manager, Ana Sanchez, wheel a small table into her office. Sitting on top of it is a bowl of water, into which Sanchez promptly dumps a cupful of cut-up green drinking straws. Freeman dips her finger in and swirls the water around and around.
“Watch what happens,” she instructs, excitedly.
Surprisingly, the straws begin to interact. They stick together, sometimes end-to-end and other times side-to-side. The more Freeman stirs the water in the bowl, the more they seem to attract to one another.
“And if we added more straws to the bowl, increasing the density, they will actually make different patterns than you’re seeing here,” she explains. “The shape of the straws and the tension of the water are why they want to connect in different ways.”
This process is called self-assembly, when a local interaction causes a disordered system to transform into an organized structure. Freeman uses this design principle to build innovative technologies. As a professor of applied physical sciences at UNC-Chapel Hill, she specializes in combining and molding biological components into functional materials where the whole is greater than the sum of its parts.
“The inspiration is anything that nature can do, and the medium is any biological material that exists in nature,” she explains. “We can design and chemically modify peptides, DNA, nucleic acids, sugars, lipids — any architectural building block that is biological. It’s a chemical approach to materials design.”
From synthetic cells to a rapid test for respiratory infections, Freeman has generated a pipeline of groundbreaking technologies that address global challenges in health care by emulating how cells build, signal, and manufacture needed components.
“My company is my lab,” she says. “We do everything from the molecular design of a chemical to the validation and application of it. We produce assets and then find an established partner who has the manufacturing, distribution, and pharmacy pipeline to get it to the market.”
Creating cell factories
In her early research, Freeman uncovered how to link peptides together by using DNA like a molecular glue. With this technique, she achieved multiple scientific “firsts,” from creating a synthetic collagen, the molecule that makes up our skin to, most recently, generating synthetic cells that can serve specific functions — like delivering drugs directly to infected cells and making plastics that eventually biodegrade.
“We want to make materials for tasks, not to last,” she says. “We want those materials to serve a task, degrade, and disappear.”
Most cell function and flexibility comes from its cytoskeleton, which provides a framework for the cell — much like the frame of a house. Freeman’s synthetic cells have functional cytoskeletons that can change shape and react to their surroundings.
The goal of this research is to make “little factories” that can imitate living cells to produce molecules like insulins.
“One of the things we’re trying to do is combine the synthetic cells with living cells and program them to make certain molecules on demand that would then be released as therapeutics in the body,” Freeman says.
These cells can also be programmed to create products cells don’t normally produce, like polymers, with the potential to replace big chemical factories.
“It would mean a future with much less waste and a much smaller footprint,” Freeman says. “That’s the idea.”