Credit: Gary Meek
A simple device could provide more rapid diagnosis of anemia and allow for inexpensive at-home monitoring, according to a paper published in The Journal of Clinical Investigation.
The disposable device analyzes a single droplet of blood using a chemical reagent that produces visible color changes corresponding to different levels of anemia.
The test produces results in about 60 seconds, and a smartphone application can correlate the visual results to specific hemoglobin levels.
“Our goal is to get this device into patients’ hands so they can diagnose and monitor anemia themselves,” said Wilbur Lam, MD, PhD, of the Georgia Institute of Technology and Emory University in Atlanta.
“Patients could use this device in a way that’s very similar to how diabetics use glucose-monitoring devices, but this will be even simpler because this is a visual-based test that doesn’t require an additional electrical device to analyze the results.”
The device was developed through a collaboration between Emory University, Children’s Healthcare of Atlanta, and Georgia Tech. It grew out of a 2011 undergraduate senior design project in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.
Using a 2-piece prototype device, the test works this way: A patient sticks a finger with a lance to produce a droplet of blood. The device’s cap, a small vial, is touched to the droplet, drawing in a precise amount of blood using capillary action.
The cap containing the blood sample is then placed onto the body of the clear plastic test kit, which contains the chemical reagent. After the cap is closed, the device is briefly shaken to mix the blood and reagent.
“When the capillary is filled, we have a very precise volume of blood, about 5 microliters, which is less than a droplet—much less than what is required by other anemia tests,” explained Erika Tyburski, the paper’s first author and leader of the team that developed the device.
Hemoglobin then serves as a catalyst for a reduction-oxidation reaction that takes place in the device. After about 45 seconds, the reaction is complete, and the user sees a color ranging from green-blue to red, indicating the degree of anemia.
A label on the device helps with interpretation of the color, or patients could use a smartphone app that automatically correlates the color to a specific hemoglobin level.
To evaluate sensitivity and specificity of the device, Tyburski studied blood taken from 238 pediatric and adult patients. Each blood sample was tested 4 times using the device, and the results were compared to reports provided by conventional hematology analyzers.
The results of the 1-minute test were consistent with those of the conventional analyses. The smartphone app produced the best results for measuring severe anemia.
“The test doesn’t require a skilled technician or a draw of venous blood, and you see the results immediately,” Dr Lam said. “We think this is an empowering system, both for the general public and for our patients.”
Tyburski and Dr Lam have teamed up with 2 other partners to launch a startup company called Sanguina to commercialize the test, which will be known as AnemoCheck™.
The test will require approval from the US Food and Drug Administration, but the researchers believe the device could be on pharmacy shelves sometime in 2016.
The team also plans to study how the test may be applied to sickle cell anemia and other diseases.
