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They’re building companies aimed at solving some of the world’s most pressing problems.

Lan Truong
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    Tammy Hsu

    Her new dye can make one of the world’s most common types of clothing more environmentally friendly.

    Many consumers don’t realize that indigo, the signature color of denim, requires synthetic chemicals like formaldehyde and cyanide, which can be harmful to workers and can sometimes contaminate local water sources. Given that jeans are one of the most ubiquitous clothing items in the world, this is a huge environmental problem.

    Tammy Hsu, the chief scientific officer of Huue, worked with colleagues to study how color is made in nature and program microbes to enzymatically produce the shade they wanted. The result is a sustainable solution that doesn’t rely on harmful processes or chemicals. Now the challenge is to make the natural dye as cheap to use as the synthetics the industry relies upon. “The chemical industry has had 100 years to hone their process and make it cost efficient,” Hsu says. “We were founded two years ago. We’re trying to catch up with that. That’s one of our biggest goals, to drive down the price of our process.”

    Huue is on track to release its indigo dye next year. Next up for Hsu is figuring out how to coax microbes to produce a range of different dyes. “We’re trying to provide the fashion industry with an alternative way,” she says. 

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    Strand Therapeutics

    Jacob Becraft

    He runs a company that’s figuring out the next steps for messenger RNA.

    Safe and effective covid-19 vaccines have finally provided an exit to the pandemic. The most innovative of these vaccines use messenger RNA—strings of nucleic acids—to instruct cells to make a protein found in the virus, causing the body to produce antibodies against it. Now scientists are eyeing all sorts of other potential uses for this underlying technology.

    “With covid-19, we have gone from mRNA being potentially useful to saying we know it works in humans,” says Jacob Becraft. He runs a startup called Strand Therapeutics, which is working on the next step for mRNA—ways to “program” the molecules to do additional useful tricks, like turn on only in specific cell types, at specific times, or automatically copy themselves so as to strengthen their effects. 

    Though mRNA’s effects are temporary (because it’s an unstable molecule), using it is in many ways simpler, safer, and faster than trying to change the genome of a cell. One idea the company is pursuing is to use injections of mRNA to instruct the body’s immune cells to attack cancers of the skin and breast. 

    Becraft grew up in a small farming community in central Illinois, famous as home to a federal lab that discovered how to mass-produce penicillin during World War II. In high school, he says, he didn’t have patience for pictures of cells, with their labeled parts. 

    “It wasn’t until college that I got exposed to biology as a machine, not just a list of things to memorize,” he says. “But when someone tells me how a system works, I get it. I can imagine it.”

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    Mammoth Biosciences

    Janice Chen

    She’s using CRISPR to make new diagnostic tests.

    Janice Chen was jumping into an Uber, cramming in equipment the size of a microwave. At the time a PhD student at the University of California, Berkeley, Chen had been invited to a lab to look for the human papillomavirus in hospital medical samples using a new technique she had created.

    Soon enough, bingo. Her test, which uses the gene-editing tool CRISPR, was able to spot the virus nearly every time, offering a new way to test for germs. She and several other students, along with Jennifer Doudna, the co-discoverer of CRISPR, cofounded a company with plans to develop a new generation of testing instruments. They called it Mammoth Biosciences.

    The diagnostics business isn’t easy to break into: a few companies with well-established technologies dominate. Chen is now in charge of a team of 40 as the chief technology officer of Mammoth. She says she leans on her experience playing chess competitively as a teenager, when she learned how to build a position move by move, make meaningful sacrifices, and get inside competitors’ minds. 

    Chen grew up in Salt Lake City. Her parents were immigrants from China. Her brother is a world champion and Olympic medalist in figure skating. When she was growing up, she says, her parents urged her and her siblings to “find your passion and do your best to move it forward in a significant way.”

    Chen crammed for years studying chess moves but ended up finding her real interest while moonlighting at her father’s biotech supply company. That’s where she first copied genes and engineered a bacterium. 

    Then, at Johns Hopkins University, she had a chance to help out on a large ongoing project to assemble the entire genome of a yeast cell from DNA parts. As an undergraduate, she did menial lab tasks. Still, here was life being engineered from the ground up. And she was part of it.

    For her PhD, Chen landed a spot in Doudna’s Berkeley lab, where CRISPR editing had been co-developed in 2012. 

    Chen joined a fast-paced hunt to discover and understand even more types of DNA editors and harness them for new uses. She demonstrated a way that a particular gene-editing enzyme could be used as a diagnostic test. Her test could find a specific sequence of viral DNA in a sample, cut it, and unleash a fluorescent signal that would report the result. 

    That looked useful enough for infectious-disease testing to try to commercialize it, which is what led her to cofound Mammoth in 2017. 

    Then came covid-19. When the rollout of the standard tests stumbled in the spring of 2020, the US Food and Drug Administration gave Mammoth and dozens of other smaller companies an emergency green light to sell their tests for the virus. It was a crisis, and that meant the purse strings were loosened too. Mammoth has won $30 million in government funding since the pandemic began. 

    As of May 2021, Mammoth was preparing to commercialize the company’s first product, kits that public health labs can use to run 1,500 simultaneous covid-19 tests with less human intervention than existing ones require.

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    Swarm Technologies

    Sara Spangelo

    Her tiny satellites could bring connectivity to the remotest places on Earth.

    Sara Spangelo didn’t quite make it as an astronaut. But four years after an unsuccessful tryout with Canada’s space agency, she’s achieved her own space milestone: unveiling the world’s lowest-cost always-available satellite communications network.

    Spangelo, who holds a PhD in aerospace engineering from the University of Michigan, is CEO of Swarm Technologies, which seeks to provide affordable data services for devices anywhere on Earth. Today, nearly 90% of the planet’s surface, including oceans, deserts, and polar regions, lacks internet access. Connecting via satellite has long been cost-prohibitive, because satellite networks typically cost billions of dollars to deploy and maintain.

    The key to lowering costs was to bring down size: Swarm’s satellites, roughly the size of a slice of French toast, are the smallest two-way communication devices in orbit today. Because they’re so compact, they can hitch rides on commercial rockets for bargain prices: total launch costs for Swarm’s full constellation of 150 satellites, which the company will finish placing in low Earth orbit by the end of 2021, will run less than $3 million. 

    Swarm’s data connection, which uses the VHF radio spectrum, won’t enable seafarers to stream Netflix: its current transfer rate of 1 kilobit per second is similar to 1990s dial-up. Swarm’s niche, rather, is giving customers the ability to transmit small yet highly useful packets of information from the world’s most far-flung places. This enables them to remotely monitor water supplies, detect leaks in pipelines, measure soil contents, track wildlife, or guarantee the temperature of vaccines in cold-chain transport.