A new vision of portable diagnostics
By Jana Manolakos
On the road to extraordinary discoveries, a team of University of British Columbia chemists connected the dots this year, and arrived at what they refer to as “biomedical selfies.”
Led by Prof. Russ Algar, Canada Research Chair in Biochemical Sensing and Michael Smith Foundation for Health Research Scholar, with financial support from NSERC, the UBC team showed that smartphones can offer a more efficient platform for clinical testing, an approach Algar says could be as simple as taking a “biomedical selfie,” a snapshot of a blood or urine sample, while waiting to be seen at a doctor’s office.
“You have medical equipment that is very expensive and typically located in specialized laboratories or core facilities or hospitals,” says Algar. “People need healthcare all over the place, and so anything we can do to make the tools for healthcare more accessible is going to lower the cost and increase efficiency of healthcare across the country.“
His team of researchers uses quantum dots to interact with smartphones like the Samsung Galaxy or iPhone. While quantum dot technology has captured the public’s interest by revolutionizing the television industry with the brightness and colour purity it brings to the screen, Algar says that the quantum dots his team applies are engineered very differently: “We use that same luminescence to analyze biological samples like blood or urine when a picture is taken of it with a smartphone camera.”
About four to 10 nanometres in size, the semiconductor nanocrystals are created by wrapping zinc sulphide around a cadmium selenide core. “From there, we attach biological molecules like peptides, antibodies, fragments of genes, other DNA or RNA,” Algar explains, “and these biomolecules are designed to seek out and bind to other biological molecules or biomarkers of a disease.”
When mixed in a chamber or a more complicated micro-fluidic technology, they’ll react depending on how they have been treated. “They could light up or change colour, or a combination of the two, and that change is then measured using the smartphone camera. The camera takes a picture of the reaction of the light emitted, and then an app on the phone will do that analysis.” Software engineers and computer scientists will be developing a specific app, which is still in the early stages.
So how reliable are the tests? Accuracy rates will depend on the type of sample, biomarker and technology, says Algar. “For one of our proof-of-concept demonstrations, we were able to show that the smartphone gave results that were equally accurate to a standard bench top instrument used in a specialized laboratory setting.”
He says that anything a doctor, clinical laboratory or hospital would test in blood, urine, or derivatives of blood like plasma or serum, could be done in principle on the smartphone platforms that they are developing. “Of course, getting to the same point of having those tests on the smartphone is going to require a lot of time, but in principle there is no reason that we can’t replace everything done in a specialized lab with smartphone-based technology.”
It becomes even more poignant in Canada, where healthcare in remote communities pales in comparison to that available in larger urban centres. In 2010, the Canadian Institute for Health Information reported that a staggering 58 per cent of patients in Nunavut had to be sent outside the territory for treatment or diagnostics. Clearly, the financial and social toll of delivering care at great distances is burdening.
“One of the great things about using a smartphone for medical diagnostics is that the information can be collected in one place and analyzed in another. So someone in a remote community or potentially in the developing world could have a test done by a local medical professional, and then the information from that test could go immediately to a big, world-leading medical centre, and a specialist there could look at that information through the Internet and help with the diagnosis and the treatment,” Algar explains. “That’s a huge benefit because the patient didn’t have to go anywhere near that big centre.”
This new diagnostic technology has the ability to show early indicators of cancer, kidney, liver, or heart disease. Outside the human body, it could identify pathogens like E. coli or salmonella in food or water. Other potential applications from a public health and security standpoint include pandemics and bioterrorism.
Most researchers will use standard materials and observe simple colour changes, but Algar’s group and others around the world are taking it further by looking at fluorescence, while showing the distinct advantages of using unique materials.
Commercially there has been a push towards smaller, lower-cost devices. Certain big companies like Abbott have had success in point-of-care diagnostics. “I think the smartphone is really the next evolution of it. But, medical diagnostics companies don’t create smartphones. So it becomes a bit of a black box – how it is going to evolve in the commercial sector once it leaves the research sector.”
Even more recently, lab-on-a-chip technology has miniaturized laboratory functions down to the micro-scale. Algar is currently engaging with people working on this latest development in microfluidic devices, to get them on board with an integrated unit. The chip can do chemistry and manipulation of different samples and reagents, “but you still need an equally portable way of reading the result of that chemistry. So the marriage between the lab-on-a-chip system and a smartphone is what I anticipate will be the pinnacle of this idea of portable biomedical analyses,” says Algar.
It’s still early days for Algar and his team as they grapple to further define the parameters. “Everyone recognizes the benefits of this, but no one really knows how it’s going to evolve commercially right now.” He acknowledges that there are still many unanswered questions. For example, how do you set up this technology to work across the different types of phones? Does it work with one, multiple or all smartphones? How will it be regulated so that when you have a smartphone from one company and a piece of test kit from a different company they are compatible?
“We are doing a lot of proof of concept research showing people that this is viable and that these materials and approaches do have advantages.” Anything that is health related has a very long process of validation, and so right now the team is in the initial stages of discovery in developing the idea, which they hope will transition into research-based clinical tests over the next five years – and eventually lead to actual clinical trials and commercialization within the next 10 to 20 years.