By Lori Brandt, Engineering Communications
Irvine, CA, December 16th, 2013 -- Malaria kills a child somewhere in the world every minute. This life-threatening disease, caused by parasites transmitted through infected mosquitoes, can be prevented and cured if detected and treated early. But malaria afflicts primarily the poor, who often do not have ready access to healthcare and who tend to live in malaria-prone rural areas in dwellings that offer few barriers against mosquitoes.
This type of global health challenge inspired biomedical engineering students at UC Irvine who participated in Calit2’s Multidisciplinary Design Program.
The program engages undergraduates campuswide in research teams co-mentored by at least two faculty members from different schools. Under the guidance of biomedical engineering professor William Tang, and public health professor Dele Ogunseitan, two student teams designed portable, low-cost, rapid-diagnostic devices using microfluidic technology. One team’s device detects malaria; the other’s, HIV.
A few students from each team were selected to travel abroad to the very places grappling with these diseases. The expeditions, supported by a $25,000 gift from Edwards Lifesciences, provided the ultimate field research experience.
Myanmar (formerly known as Burma) accounts for the vast majority of malaria cases and deaths in Southeast Asia. The country’s poverty impels its residents to move back and forth into neighboring countries looking for work and seeking adequate healthcare. This migration spreads the disease, increases reinfection and leads to inconsistent treatment.
Reaz Rahman was one of four biomedical engineering students who went to the Thailand-Myanmar border to study the spread, diagnosis and treatment of malaria. Working through the NIH’s International Centers of Excellence for Malaria Research and with public health professor Guiyun Yan, Rahman witnessed the impact malaria has on the lives of Thai villagers and Burmese refugees.
The students accompanied local health workers as they screened villagers for fever, a symptom of malaria. If fever is identified, the health worker takes a finger prick blood sample and transports it back to the clinic to test for infection.
The team’s project is a portable, low-cost, microfluidic diagnostic device, which uses saliva instead of blood to test for malaria. (Microfluidics involves extremely small volumes of liquid, nano or micro liters, to detect antigens or reactions to a virus or disease.)
The approach targets a specific enzyme reaction present in the saliva of a person with the disease. If the reaction occurs, the enzyme acts as a catalyst, lighting up an LED connected to an electric circuit in the device, indicating the presence of malaria.
“The experience I gained from doing [this] field research is unlike any education I have ever received before,” says Rahman. “It was something I could never have learned from a book. Seeing the diagnostic process helped me understand the need for better and more advanced diagnostics that would improve lives.”
Ogunseitan, chair of UCI’s program in public health, says developing nations present many challenges in the collection of blood for diagnosing both malaria and HIV. “We see issues with storage, adequate refrigeration and cross-contamination. People who have malaria, particularly chronic malaria, are often anemic as well, so you don’t want to take too much blood from them. And in places where HIV/HPV are endemic, there is also a lot of stigma associated with the disease, so there is a need for discreet, rapid testing that uses a small amount of fluid.”
Vladimir Satchouk’s student team designed a rapid HIV test, the size of a credit card. The microfluidic device contains test reagents and a place to add a blood sample. The reagents and blood are held at atmospheric pressure in wells etched into the plastic, while the rest of the card is sealed below atmospheric pressure.
The user simply pricks his or her finger, places a small drop of blood in the collection site, and pulls an adhesive strip. This breaks the hermetic seal between the reagents and the reaction area, creating a difference in pressure between the two sides that drives the fluid flow. The flow of reagents is controlled by varying lengths and widths of the fluid channels so each reagent reaches the test site at precisely the right time. If the patient is HIV positive, the reaction site turns black, giving a clear yes-or-no diagnosis.
Under the guidance of professor Brandon Brown from UCI’s program in public health, Satchouk and Nigel Fernandez traveled to Lima, Peru, to visit HIV/STD patients and clinics among the region’s gay and transgender sex workers. “The issues marginalized groups such as sex workers face in developing nations was a motivating reason behind the genesis of our project,” he explains.
Satchouk’s group returned from the expedition with a new appreciation of the struggles faced by the LGBT community in a conservative Catholic society. Group members determined that its diagnostic device should include testing for STDs as well.
“From a holistic perspective, the exposure to other cultures, customs and socioeconomic classes was of incalculable educational and personal value,” he says.
“I was extremely excited with the outcomes from these expeditions,” says Tang, who initiated the trips in an effort to enhance BME students’ senior design experience. “Even though traveling to these areas was strenuous and taxing, in the end, all the students came back transformed in their ideas about biomedical engineering. They were fired up and excited about continuing in this line, almost as a life calling or mission.”