New smartphone clip-on can detect Zika virus in blood samples: Study
It is mainly transmitted by the mosquito Aedes aegypti. Although the disease is largely asymptomatic or causes mild symptoms in adults, it causes developmental disorders in infants if their mothers are infected during early pregnancy.
Currently, the virus is circulating in more than 87 countries, infecting thousands of people every year, better testing and control measures are needed.
“Mosquito-borne viruses cause serious illnesses, but they have similar symptoms,” said Brian Cunningham. (Director of CGD/MMG), Intel Alumni Emeritus Favored President of Electrical Engineering, and Computer.
How to detect Zika virus?
Zika virus infection is currently detected through polymerase chain reaction tests performed in the laboratorycan amplify the virus’ genetic material, allowing scientists to detect it.
In the new study, the researchers used Loop-mediated Amplification to detect the virus in blood samples using an approach tailored to healthcare clinics. Whereas PCR requires 20-40 repeated temperature changes to amplify genetic material, LAMP requires only one temperature – 65°C – making it easier to control.
In addition, the PCR test is very sensitive to the presence of contaminants, especially other components in the blood sample. As a result, the sample is first purified before it can be used. On the other hand, LAMP does not require any such purification step.
A cartridge, containing the reagents needed to detect the virus, is inserted into the device to perform the test while the device is clamped to the smartphone. When the patient adds a drop of blood, a set of chemicals breaks down the virus and blood cells within five minutes. The heater underneath the cartridge heats it up to 65°C.
A second set of chemicals then amplifies the virus’ genetic material, and the liquid inside the cartridge fluoresces bright green if the blood sample contains Zika virus. This whole process takes 25 minutes.
“Another interesting aspect is that we’re doing smartphone reading,” Cunningham said. “We designed a clamping device so that the smartphone’s rear camera looks at the cartridge while amplification occurs. When there’s a positive response, you’ll see small green fluorescence beams. eventually fill the entire cartridge with green light.”
The researchers are currently developing similar devices to detect other mosquito-borne viruses simultaneously, and are working to make these devices even smaller. “Although our clip-on detector is quite small, a lot of space is already occupied by the battery,” Cunningham said. In the next version, it will be powered by the phone’s battery.
Study “Smartphone clamp and microfluidic processor for rapid detection of Zika virus detection in whole blood using RT-LAMP in space” published in the journal Analyst expert.