Jaya Khullar | January 4th, 2025
High up in Stevenson 5, sunlight shines through the many windows along the walls of the Haselton Lab. With a special focus on global health, the Haselton Lab aims to develop technologies that address the needs of physicians and patients in low-resource settings.
David Evans, a biomedical engineering PhD student and member of the research team, shares that goal of the lab.
“Engineering is typically high-resource focused, so I saw a need there for formulating accessible medical device design and working in that sector of biomedical engineering,” Evans said. “The low-resource, affordable-healthcare focus of the Haselton Lab clicked with me.”
Evans recently ventured across the equator to Cape Town, South Africa to test technology the Haselton Lab has spent the last few years developing.
“Going to Cape Town was my first time testing the technology I’ve researched in a low-resource region,” Evans said. “I’m specifically researching tuberculosis, which is not very prevalent in the United States. I went to South Africa for two weeks to collect clinical samples from tuberculosis patients that this technology could be tested on.”
In Cape Town, Evans was able to view firsthand the medical challenges faced by patients in low-resource regions.
“There’s a lot of poverty and people living with little or no healthcare,” Evans said. “Cape Town is a great location because they have the capability to do a lot of research in the city, but there’s access to low-resource areas and clinics to collect samples from to test. Healthcare is a completely different experience in Cape Town, and we engineers often try to use our own experiences or understandings to approach challenges. But you have to take a 180º perspective and learn from the people around you to address these challenges.”
The technology Evans is testing aims to increase equitable and reliable diagnostics for tuberculosis.
“Tuberculosis is typically diagnosed with sputum samples, which is this gunk produced in the lungs when there’s infection,” Evans said. “But people with HIV can’t produce sputum very well, and regions like South Africa that are adversely affected by tuberculosis are also adversely affected by HIV. There is a need for a non-sputum based diagnostic.”
To counter traditional sputum-based means of diagnosis, he is analyzing markers of tuberculosis DNA in urine samples, which is what the developing technology hopes to make easier to carry out.
“There’s tuberculosis in urine samples that we can detect markers of, but it’s really dilute, making it difficult to detect tuberculosis in urine via traditional diagnostics,” Evans said. “By using magnetic beads coated with synthetic DNA strands that bind to tuberculosis DNA, we can magnetically concentrate those beads down into a low-volume solution that is not so dilute and reconstruct fragments of tuberculosis into longer strands to be read.”
The results of Evans’s continued research in Cape Town have yet to be fully determined, but the initial data is promising.
“We want a greater than 80% sensitivity and a 95-100% specificity, and our data is so far showing an 80% sensitivity and a 90% specificity,” Evans said. “We also reduced the sample volume from 10 milliliters to one milliliter, which differentiates us from similar research and improves our outcomes. This tech in and of itself isn’t something that can yet be implemented into low-resource clinics, but being able to use cell-free techniques for diagnoses opens up possibilities. It’s about improving and developing the technology step-by-step.”
An endpoint — a usable test for diagnosing tuberculosis via urine samples — is still in the works for the Haselton Lab, but Evans maintains his passion for healthcare equity.
“Over time, I’ve recognized that privatized healthcare is difficult,” Evans said. “I don’t know what the solution is, but I do see I can do my part to make healthcare more accessible. I recognize the grace I’ve been given, and that’s my motivation to outpour that to others.”
