Researchers from the Indian Institute of Technology (IIT) Kharagpur have developed a portable tabletop machine that can diagnose coronavirus disease (Covid-19) test within an hour.
The device, named ‘Covirap’, has been validated by the Indian Council of Medical Research (ICMR) and the researchers are in talks with manufacturers to market the product. With a sensitivity of 94% and specificity of 98%, it’s almost as accurate as the gold-standard reverse transcriptase-polymerase chain reaction (RT-PCR) test.
It makes accurate Covid-19 diagnosis cheap, fast and accessible. The cost of the machine will depend on the level of automation needed, but at the laboratory setting, it cost the team Rs 5,000 to manufacture the machine. The cost of each test will be around Rs 500 to Rs 600.
“There is no need for a temperature-controlled laboratory for the device or a cold chain for the reagents. The master mix of reagents is available in test tubes that have to be mixed with the RNA sample collected from the patient and run in the machine. After the processing is complete, a simple paper strip dip test has to be done. To ensure accuracy in reading the test, even without trained professionals, the strips have to be put in a small cartridge and a mobile-based system reads it to give results. Multiple tests can be run in a single cycle,” said Dr Suman Chakraborty, professor in the department of mechanical engineering at IIT-Kharagpur.
The device uses one human gene as control and two genes from Sars-Cov-2 to detect the infection.
Dr Arindam Mondal, a part of the team that developed the machine and assistant professor in the school of biosciences at IIT-Kharagpur, said, “During the testing phase of patient samples, all kits developed by the institute, were transported in an uncontrolled environment for hours to the testing unit that shows high levels of stability of the reagents that are being used for the testing.”
“To check the performance of the device, we tested 200 patient samples using both RT-PCR and Covirap. We were pleasantly surprised; the results of both the assays were comparable. In fact, the sensitivity and specificity went up to 99% if RT-PCR results where less than 30 cycles of amplification were needed were considered,” said Dr Mamta Chawla Sarakar, virologist from the ICMR-National Institute of Cholera and Enteric Diseases, where the kit was validated.
The researchers not just developed the machine, but the method used is also completely new. The team has applied for an Indian patent for the process.
The machine is based on a technology called Reverse Transcription-Loop Mediated Isothermal Amplification (RT-LAMP) that uses constant heat to amplify the genetic material of the virus. After the pre-programmed amplification, the method developed by researchers from IIT-Kharagpur uses an additional heating step that improves the accuracy of the test.
“This second heating step – and I cannot provide much detail – has been patented by our team. It is not used anywhere in the world. And, it’s not just Covid-19, this machine can be used to test for other infections such as tuberculosis, dengue, and malaria at low cost without much infrastructure. We kept in mind the situation in Kharagpur, from where people have to be rushed to Kolkata for any medical emergency,” said Dr Chakraborty.
“While the institute can produce the testing kit up to a certain scale, patent licensing will facilitate commercialisation opportunities for medical technology companies,” said Dr VK Tewari, director, IIT-Kharagpur.
“The innovation has made high-quality and accurate Covid-19 test affordable for the public. A test conducted by Covirap costs around Rs 500. The price point can further be reduced through government’s intervention. The machine can be developed at a cost of less than Rs 10,000 with minimal infrastructure requirements. The portable device has made the technology affordable for the public. Besides, the test results can be made available within an hour,” said Union education minister Ramesh Pokhriyal ‘Nishank’.
He said the device would impact the lives of people living in rural India, as it could be operated on a low-energy supply. Minimally trained rural youths are also equipped to operate the machine, he added.