Gitanjali Rao is already on the 2019 Forbes 30 Under 30 list and she hasn't even made it to high school yet.
In 2017, the then 11-year-old from Lone Tree, Colo. was named 'America's Top Young Scientist' for the design of a small, mobile device that tests for lead in drinking water.
Rao hasn't stopped there. She's now getting help from scientists in the water industry to create a working prototype of the device that could eventually be on the market.
Rao's invention is named Tethys, after the Greek Titan goddess of clean water. The 3D-printed box is about the size of a deck of cards and contains a battery, bluetooth and carbon nanotubes. Rao got the idea after reading about how similar technology can detect hazardous gas in the air. Her immediate reaction was "why not use carbon nanotube sensors to detect lead in water?"
The Flint water crisis was the motivation behind the invention.
Rao remembers watching her parents try to test their drinking water with an at-home test strip kit. The results seemed inconclusive and unreliable. The other option was to send a water sample to a lab.
"[Tethys] is for people who don't really know what's in their water from the pipes leading to their house. My target market right now is people in their homes as well as schools," Rao said.
Here's how it works: Carbon atoms link together in a beehive shape and connect to create a tube — a nanotube. The carbon nanotubes respond to changes in the electron flow. If there is lead in the water, the lead sticks to the carbon ions, creating resistance. Tethys measures that resistance, and sends the data to a smartphone app to give the status of lead in water.
Selene Hernandez-Ruiz, a lab manager at Denver Water, has partnered with Rao to test and improve her device. The two started working together after Rao was invited to take a tour of Denver Water's facilities.
Hernandez-Ruiz told Rao she could come back if she wanted to use the lab. The 13-year-old was hooked, "I asked, can I come here, like, everyday?"
Hernandez-Ruiz and Rao get together about once a month to work on the device and test its results.
"Right now, I'm looking at interference with other chemicals in water apart from lead," Rao said. "Like, what if [the carbon] accidentally binds to fluoride? So that's kind of what I'm trying to tackle."
Hernandez-Ruiz is thrilled to help a young woman of color foster a passion for science.
"It's so hopeful to see the current and next generation going for it," she said. "With really the desire to excel and test those boundaries that sometimes we're told we're not supposed to come close to."
Rao is thankful for the opportunity Denver Water has given her to continue to work on her device.
"My mom won't let me use lead in our backyard," Rao said with a laugh. "This gives me the potential to take [Tethys] out there. I know my device can be accurate."
Rao hopes to get a prototype out into the world in the next two years. In the meantime, she's filling up her inventor's notebook with new ideas.
ARI SHAPIRO, HOST:
Now we have a profile of an inventor from Colorado. She's already made it onto the 2019 Forbes 30 Under 30 list for top young scientists, but she has not even made it to high school yet. She's 13. Her most famous invention so far - a mobile device that tests for lead in drinking water. Here's Colorado Public Radio's Michael Elizabeth Sakas.
MICHAEL ELIZABETH SAKAS, BYLINE: Gitanjali Rao opens her closet door and shows off her game collection.
GITANJALI RAO: So I'm slightly overly obsessed with board games, as you can probably see here.
SAKAS: A dozen or so are stacked roughly in her closet. She says her favorite is Clue because she wins. And her favorite character - Professor Plum.
RAO: He looks like somebody who would love science, and so I like him.
SAKAS: Because Rao definitely loves science. There's a pennant flag from MIT hanging on her bedroom wall. Her dream is to go there to study genetics. There's a desk not far from her bed which she calls her lab. It's complete with a 3D printer, test tubes.
RAO: And here's my inventor's notebook, which I love, a graduated cylinder. I've got a little box of lead (laughter).
SAKAS: And there's the lead detection device she designed and named Tethys after the Greek goddess of clean water. It's a 3D-printed box about the size of a deck of cards. So how does it work?
RAO: A carbon nanotube sensor detects the lead in the water and forms resistance.
SAKAS: OK. What she's saying is carbon atoms link together in kind of a beehive shape and then become a tube. Lead sticks to the carbon ions which creates resistance.
RAO: So I have a processor that measures the resistance and sends the data to a mobile phone once you connect over Bluetooth, and it gives you the status of the lead in your water.
SAKAS: Rao got the idea after reading about the same technology used to detect hazardous gas in the air.
RAO: And my immediate reaction was, why not use carbon nanotube sensors to detect the lead in waters? And that's a problem which I'd heard about three years ago during the Flint water crisis.
SAKAS: As a 12-year-old, she was named America's Top Young Scientist by Discovery Education, and she landed an interview on "The Tonight Show With Jimmy Fallon" (ph).
(SOUNDBITE OF TV SHOW, "THE TONIGHT SHOW STARRING JIMMY FALLON")
JIMMY FALLON: When I was 12, I don't know what I was thinking. I was lip-syncing in my mirror in my bedroom.
SAKAS: Rao says the fame helped her make friends at school when her family first moved to Colorado. Kids already knew who she was.
RAO: Oh, you're that lead girl, right? I'm like, yeah, I'm that lead girl. And they're like, do you want to be friends? I'm like, yeah, sure. Let's do this.
SAKAS: Now she's working to create a prototype of Tethys that could eventually be on the market, and she's getting help from scientists in the water industry. Rao stands at a whiteboard with Dr. Selene Hernandez Ruiz, a lab manager at Denver Water, Colorado's largest water utility. She's brainstorming with Rao on what they'll be working on that day.
RAO: Right now, I'm looking at interference with other chemicals in water apart from lead.
SAKAS: This partnership started when Hernandez Ruiz invited Rao to come work in the lab after Rao took a tour of Denver Water.
RAO: I hooked on, and I was like, hey, I want space in your lab. Can I come here, like, every day?
SAKAS: Hernandez Ruiz says she's thrilled to be helping a young woman of color foster a passion for science.
SELENE HERNANDEZ RUIZ: So hopeful to see the current and next generation like Gitanjali going for it so strong - right? - with all the right tools, with really the desire to excel and test those boundaries.
SAKAS: Rao hopes to get a prototype of her device out into the world in the next two years. In the meantime, she's filling up her inventors' notebook with new ideas. For NPR News, I'm Michael Elizabeth Sakas in Denver. Transcript provided by NPR, Copyright NPR.