COVID-19 Diagnostic Test Kit Via Smartphone Camera Now Possible, How Does It Work?

In a move that is expected to reduce time and increase efficiency and accessibility, researchers have found a way to turn an ordinary quantum dot smartphone camera into a vision system for a new COVID-19 diagnostic test kit.

The new engineering marvel in the COVID-19 effort was the brainchild of researchers from the Terrence Donnelly Centre for Cellular and Biomolecular Research at the University of Toronto. Working with Sunnybrook Health Sciences Centre, Public Health Ontario, and Mt. Sinai Hospital, the researchers believe that this could significantly reduce the turnaround time compared to existing diagnostic test kits and improve the efficiency of diagnosing infectious diseases like COVID-19 and others like it.

Details of the new quantum dot smartphone camera diagnostic test kit are reported in the article "Surveilling and Tracking COVID-19 Patients Using a Portable Quantum Dot Smartphone Device," published in the latest Nano Letters.

Making COVID Tests More Accessible

"The goal of the study is to make COVID-19 antibody tests more accessible," explains Johnny Zhang, one of the co-first authors of the study and a Ph.D. candidate from the Institute of Biomedical Engineering and Department of Chemistry, in a news article from the University of Toronto. He adds that with their design, patients can take self-diagnosis for COVID-19 with their quantum dot smartphone, with the data being accessible online for evaluation by medical professionals.

Following traditional diagnostic testing processes for infectious diseases, the clinical sample is first taken from a patient and is sent to a laboratory for testing. The result from the laboratory is then reviewed by concerned clinical personnel for decision making. These separate steps are often independent of each other and lead to increased turnaround time.

In their new diagnostic test, researchers worked with quantum dot barcoded microbeads and a secondary label, which they used to search for antibodies against COVID-19 in the blood of a patient. Detecting the presence of antibodies creates a change in the color of the microbead emissions. Then, the beads are loaded into a device where a laser activates the material. The signal emitted is imaged by the quantum dot smartphone camera, with a customized system collecting the data and transmitting it for further analysis and decision making.

All of these processes are now done in a single, compact unit.

Building on a Growing Technology

The University of Toronto article additionally explains that the technology — quantum dot microbead detection used for finding and measuring small biomarkers in blood — has been in development over the last decade. In 2016, for example, a published study on Talanta presented a new multiplexed detection and analysis method that has been developed based on quantum dots and microbeads used to identify a set of biomarkers associated with lung cancer.

Ayden Malekjahani, also a co-first author of the new study, shared that their team was keen on improving the performance and use of the existing technology — a thing it did in the ongoing fight against the coronavirus pandemic. The co-first author also added that simply detecting these antibodies in the patient is not enough, leading them to add more functions to the kit. It led to the quantum dot smartphone camera diagnostic test kit being able to detect multiple antibodies from various sample types, maximizing the information it delivers.

Check out more news and information on Smartphones in Science Times.