While we’ve got a long way before medicine catches up with the treatment available in the sick bay on Captain Kirk’s Starship Enterprise, Keith Neeves, assistant professor of chemical engineering, is exploring some very exciting medical frontiers. He develops technologies to fine-tune drug delivery.
“It’s personalized medicine,” says Neeves, “where you get the exact amount of medicine you need for your condition.”
In one project, Neeves is working with hematologists at the Denver Children’s Hospital to help them better understand blood-clotting mechanisms using a “microfluidic device.”
He explains that clotting is triggered when cell walls are damaged, exposing what is called the “subendothelium matrix.” Blood platelets adhere to this matrix and accumulate at the site, forming a clot. When an injury triggers this response, the logjam of platelets can plug the cut, preventing loss of blood—a good thing.
However, the system can go awry. When too much clotting takes place within a vessel, it can restrict blood flow—a condition called thrombosis. If a piece of a clot breaks away and is carried off in the bloodstream, the “embolism” can get lodged and restrict blood flow elsewhere, sometimes with dire consequences—in the case of stroke victims, clots travel to the brain, where loss of blood circulation can cause permanent disability or death. On the other hand, when platelets fail to clot, internal or external bleeding can also be life-threatening.
While drugs can suppress or promote clotting, effective dosing varies considerably from individual to individual. Doctors rely on lab results to determine doses, but these tests have some serious shortcomings, according to Neeves. “Most of the current diagnostics are performed under static, no-flow conditions,” he explains. To get meaningful information about the concentration of a drug needed to inhibit or promote clotting, platelets must be observed under flow conditions, he argues. Without this, “it’s hard to predict how bad a patient’s bleeding problems are and how much [medicine] they’ll need,” he says.
Here is where Neeves’ work is groundbreaking. Using nanotechnology, he’s developed a minute, but highly sophisticated “lab on a chip” capable of recording platelet behavior in blood at varying pressures and flow rates. By circulating a small blood sample inside the device and slowly increasing the concentration of a drug, clot formations can be observed and drug dosages for that individual can be determined.
This research track is an extension of a long-held interest in the connection between engineering and medical science. During his tenure as a graduate student at Cornell University, Neeves began investigating the use of nanotechnology to deliver medicines to the brain. “My inspiration comes from finding a niche where engineering can contribute to [solving] medical problems,” he explains.
Another medical problem Neeves has studied is drug delivery to the brain. One of the shortcomings of brain drug delivery is the inability to control where medicines flow. “You’ve got to think about the brain as a heterogeneous porous medium,” says Neeves, “where [drugs] will follow the path of least resistance.”
In a surprising analogy, he compares this medical challenge to the engineering challenge of getting oil in a depleted well to flow in the desired direction. Just as liquids are pumped at high pressure into the ground at one point, so oil is pushed toward another point, Neeves’ research involves injecting medicine into the brain under pressure at specific points to propel delivery in a specific direction. The procedure has gone through five years of clinical trials, with six trials targeted specifically at brain tumors.
More recently, he has been building on this work by looking for natural pathways in the brain along which drugs flow more easily: “I am looking to use multiple infusion points to map out the permeability of the brain,” he says. One way he thinks its possible to open up a pathway for drug delivery is by introducing a high-concentration solution that “tricks” cells into shrinking; this ultimately results in a higher “free space” within the brain so large nanoparticle drug carriers can flow without restriction.
Ultimately, Neeves hopes that his research will make its way into mainstream medicine, whether through a personalized diagnosis of blood at the bedside or a method to more effectively treat brain conditions. “These problems are chemical engineering phenomena applied in biological systems,” Neeves explains. “The success I’ve had comes from creating new technologies that allow for treatments and diagnostics that were impossible by conventional methods.”
Major: Engineering—Civil Specialty
Standing on the podium in Beijing singing “The Star Spangled Banner” with her gold medal around her neck and her hand on her heart, Jackie Barnes was moved by a flood of emotions: patriotism, pride, relief, excitement, accomplishment. It was one of the most memorable moments of her life.
Jackie and her teammates had just beaten China in the final match of the goalball competition—one of several sports in which the sight-impaired competed during the 2008 Paralympics. Playing before a standing-room-only crowd of 6,000, the match had been close—the final score was 6-5—making this moment of triumph all the more poignant.
Less than one week later, Jackie was back on the Mines campus where she is majoring in engineering, civil specialty. Legally blind since the age of 13, Jackie came to Mines as a freshman in 2005 after graduating from Stevenson High School in Lincolnshire, IL. She first heard about Mines from a neighbor, Michael Berry ’03, and it sounded like just the right kind of school in just the right location: she enjoyed math and science, she would be near her teammates in Colorado Springs and she was ready for a big move. “I wanted distance,” she said.
While many in her shoes might have been daunted by the challenge of moving so far from home, Jackie looked forward to it. “I didn’t come here with a friend, and I didn’t know anyone on campus. I just went out on a limb and headed over and tried to meet as many people as I could,” she recalled. “I wasn’t really scared to go to college; I was more excited.” And having already traveled internationally on several occasions with her team, it wasn’t as if this was her first time away from home. Now in her fourth year, she’s very much at ease on campus. “I know the school inside and out,” said Jackie, who only needs to use a cane when she leaves campus at night.
Getting comfortable academically was a greater challenge than settling in socially. At Stevenson High School, she had support from educational specialists knowledgeable about her learning needs, but now she needed to be more proactive. “I’m an auditory learner,” she says. “I meet with professors at the beginning of the semester and explain my needs—I teach them how to teach me. And if professors reference information on a blackboard during class without describing it, I go ask them for an explanation afterward.”
Jackie is modest about her accomplishments at Mines, but given that she's taking subjects most often taught with visual media and mathematical proofs, her above-average GPA is an impressive achievement. What's more, on top of her academic schedule, she works out every weekday, and on Saturday morning gets up before dawn to catch a bus to Colorado Springs. “We train most weekends,” Jackie explains. “The coach and most of my team is based there.”
Jackie has played sports as long as she can remember. Her mother, Cynthia Barnes, saw to that. “We signed her up for everything,” she said. “She played baseball and soccer and basketball.” Of the three, soccer was the one Jackie took the furthest, first getting picked for the league’s traveling team, and later playing soccer on her high school freshmen team.
Told at the age of 8 that she was losing her sight, she continued to play as long as she possibly could. By 13 she was legally blind, but still playing. “When the coach subbed me in for another athlete on the field, I’d just look for someone running off the field and go in that direction. I couldn’t really see the ball until it came close to me, so I was following the crowd instead of the ball,” admitted Jackie.
“Her coach didn’t even know she was visually impaired. She’s always been competitive. She’s always been independent,” said Cynthia. “We used to joke that the first sentence out of her mouth was, ‘I’ll do it myself.’”
Although Jackie first discovered goalball when she was 12, she didn’t take it seriously until after she had to give up soccer. “When I was 14, I started playing regional tournaments competitively within my state. It was when I was a sophomore that I started to go to national training camps, and by my junior year I was an alternate [for the national team].” Over the last four years, her team has brought home a string of titles, one of their most notable being a gold medal at the Para Pan American Games in Sao Paulo, Brazil, in 2005. Now they’ve topped that. “Four plus years of training came down to the last 49 seconds,” said Jackie. “It was the most important competition of my life. I’ve always loved being competitive in sports. Now I’m ready to go out and be competitive in my profession.”