New device clips onto smartphone for real-time detection and analysis of diseases
For movie characters, viruses can come from anywhere including the deeps of space. If you’re one of the unfortunate inhabitants of the movie Virus, you might even find yourself at the mercy of an intelligent virus moving through your electronics. In the real world, that fortunately hasn’t happened — and hopefully never will — but that doesn’t mean we can’t get human-infecting pathogens and technology to interface in meaningful ways.
Enrique Valera of the Department of Bioengineering at the University of Illinois, and colleagues, have developed a device capable of clipping onto a smartphone for real-time detection and analysis of diseases. The device is reported in the journal Analyst.
In the current study, the team used their device for the detection of Zika virus, a disease which is transmitted by mosquitos. There’s a distinct opportunity to improve the detection of Zika because it is largely asymptomatic in most of the population but can cause significant birth defects if a patient is pregnant during infection. Moreover, bloodborne diseases are of particular interest with regard to the simplification of detection because conventional tests require significant preparation of the sample in advance.
“We develop microfluidic devices for the detection of bloodborne pathogens, among other things because one of the great challenges for this type of device is working directly with whole blood. Working directly with whole blood is challenging due to the large number of cells in the blood. Our device avoids the need for any prior blood treatment,” Valera told SYFY WIRE.
Existing processes for detecting pathogens are often complex and require specialized knowledge or equipment to prepare. Researchers wanted to develop something easy to use and self-contained, such that anyone could self-test for a number of diseases.
Their device works in two parts, the sample cartridge and the detector. The cartridge uses chemical lysis to release viral RNA from the blood, in this case from the Zika virus. The RNA is then amplified using a process known as loop-mediated isothermal amplification, otherwise known as LAMP. Importantly, there isn’t any heat treatment or purification needed in advance, making this system advantageous over existing methods. Once amplified and exposed to a buffer, the viral RNA will fluoresce and become visible. That’s where the smartphone comes in.
“In the second part of the device (Module B) we heat the solution to amplify the RNA molecules from the virus and we can see this amplification event optically. We have a smartphone-based reader that can read and find the fluorescence event in real time. We correspond an increase in fluorescence with the presence of the virus,” Valera said.
During tests, the device was able to confirm the presence of Zika in a sample in as little as 22 minutes, making the entire process from sample to detection roughly half an hour. At present, the device has a dedicated battery, but the team is working on streamlining the design. In the future, they envision it using the smartphone’s battery for power. They also have other improvements in the works. In addition to expanding the types of pathogens their device can detect they’re also working on getting it to detect multiple pathogens at the same time.
“Bloodborne viruses can have many similarities in characteristics and transmission. There is the possibility of co-infection of the same individual with more than one virus. The goal is to be able to test the same blood sample for multiple viruses to find one, but also rule out others,” Valera said.
Of course, expanding the utility of the device will require innovations in the way it detects pathogens. Right now, it’s looking for RNA in droplets of blood, but testing for other pathogens might require an ability to look inside of saliva and other testable body fluids. Each of those have different challenges and mechanisms for detection. The upshot is that the detector can be reused. Unlike conventional test kits which are single use, the smartphone detector could utilize disposable detection cartridges while allowing the detector itself to remain uncontaminated.
Valera envisions a future in which their devices are not just in clinical settings like doctor’s offices and hospitals, but could be taken into the home, giving consumers access to real-time diagnoses. Who would have thought you could find out what’s making you sick in between surfing the web and playing Angry Birds?
