A portable, ultrasensitive saliva-based COVID-19 test which is read by a smartphone within 15 minutes has been developed by scientists in the US.
According to a study published in journal Science Advances, the researchers said, “We believe this smartphone platform, a similar future application, offers the potential to rapidly expand COVID-19 screening capacity, and potentially simplify the verification of contact tracing, to improve local containment and inform regional disease control efforts.”
“Herein we describe the development of a portable, ultrasensitive saliva-based COVID-19 assay with a 15 minute sample-to-answer time that does not require RNA isolation or laboratory equipment,” the study said.
To verify the utility of this design, the scientists said they employed an on-chip CRISPR-FDS assay to analyse saliva from 12 COVID-19 patients and 6 healthy controls, it successfully distinguished between patients with and without the virus.
“Saliva samples offer practical and logistical advantages for diagnostic and screening efforts, since they can be directly collected by the patient, reducing the need for, and exposure risk of, medical personnel,” the researchers said.
“Saliva samples also do not need to be collected in airborne infection isolation rooms, which allows collections in outpatient clinics, community testing sites, or other locations as needed to meet local needs. Both these features could improve potential testing bottlenecks and enhance diagnostic and screening efforts by reducing the labour required from medical professionals,” they added.
“This test addresses the critical needs for a rapid, ultrasensitive COVID-19 diagnosis along with effective large-scale screening efforts,” Tony Hu, corresponding author of the study and Weatherhead Presidential Chair in Biotechnology Innovation at Tulane University School of Medicine, told the university’s website. “Our development can quickly identify patients who have the virus, which is required to help address the ongoing threat to public health worldwide.”
“The sensitivity and simplicity of this test, its straightforward sample collection procedure, and the inexpensive nature of the readout device should permit the rapid translation of this approach to COVID-19 testing efforts once we obtain FDA approval,” Hu said.