|The new ELISA platform is created with a 3-D printer and attaches to a smartphone.--Courtesy UCLA|
Diagnostic assays that usually require a desktop reader that costs several thousand dollars can now be done using a 3-D-printed plate that attaches to a smartphone. Even better, the accuracy of the results achieved are comparable to standard laboratory equipment.
The device developed by researchers at the University of California at Los Angeles consists of a traditional ELISA (enzyme-linked immunosorbent assay transparent) plate with 96 tiny wells that attaches to a smartphone. The device illuminates the plate with light-emitting diodes. The light projects through each well and data is collected via 96 individual plastic optical fibers.
The smartphone transmitted the resulting image to UCLA servers via a custom app. The images are analyzed using an algorithm that the researchers wrote; results are sent back for each of the 96 wells to the phone within about one minute and the app can create a visualization of the results for the user.
"It is quite important to have these kinds of mobile devices, especially for administering medical tests that are usually done in a hospital or clinical laboratory," Aydogan Ozcan, the associate director of the California NanoSystems Institute and Chancellor's Professor of Electrical Engineering and Bioengineering at UCLA, said in a statement. "This mobile platform can be used for point-of-care testing, screening populations for particular diseases, or tracking vaccination campaigns in most resource-poor settings."
Ozcan led the research along with professor of bioengineering Dino Di Carlo and Omai Garner, associate director of clinical microbiology for the UCLA Health System. But the lead author on a study published in the journal ACS Nano was Brandon Berg, a UCLA undergraduate. Two additional undergrads also contributed to the research, which was supported by the National Science Foundation and the Howard Hughes Medical Institute.
ELISA is widely used, particularly in a hospital setting, to diagnose a number of diseases including HIV, West Nile virus and Hepatitis B. In ELISA, sample antigens are placed in the wells, then a specific antibody is placed on it so it can bind to the antigen. The antibody is linked to an enzyme; when the enzyme's substrate is added it produces a detectable signal, most commonly a color change.
In their study, the academics compared the smartphone-based device results with those from standard, FDA-approved, well-plate readers in a UCLA clinical microbiology laboratory.
They found that in 571 patient samples, the mobile device was 99.6% accurate in mumps diagnoses; 98.6% accurate in measles diagnoses; and 99.4% in diagnosing herpes simplex 1 and 2.
"Our team is focused on developing biomedical technologies that work with mobile platforms to assist with on-site testing and health-care in disadvantaged or rural areas," Berg said.
Added Di Carlo, "We are always looking toward the next innovation, and are looking to adapt the basic design of this ELISA cell-phone reader to create smartphone-based quantified readers for other important medical tests."
- here is the release