We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress hp
Sign In
Advertise with Us
PURITAN MEDICAL

Download Mobile App





New Lateral Flow Test is Cheaper, Easier to Use and as Reliable as PCR Test for Diagnosing SARS-CoV-2 Infection

By LabMedica International staff writers
Posted on 22 Jun 2021
A SARS-CoV-2 lateral flow test that combines two bacterial enzymes with genetic sequences and a couple of probes is cheaper and easier to use than PCR tests while producing comparably reliable results. More...


Called Vigilant and designed at King Abdullah University of Science and Technology (KAUST; Thuwal, Saudi Arabia), the test can detect very small amounts of viral RNA in a sample. PCR tests, which are conducted in laboratories, produce more reliable results but are expensive and require sophisticated equipment and skilled personnel.

The first critical step of the Vigilant platform involves a technique called reverse transcription-recombinase polymerase amplification (RT-RPA) to make many copies of a specific region on the SARS-CoV-2 genome, if it exists in a person’s nose and throat swab sample. PCR tests also amplify viral gene sequences in samples but involve putting the samples through multiple high and low temperature cycles. RT-RPA can be done at room temperature with much cheaper and easy-to-use equipment.

Any SARS-CoV-2 amplified genes in the product of this process are tagged with a molecule called biotin, then added to a test tube containing KAUST’s specially designed detection complex. This complex is formed of two enzymes. On one end, a bacterial enzyme called Cas9 is conjugated with an RNA guide that only recognizes and attaches to the corresponding SARS-CoV-2 gene sequence. On the other end, another bacterial enzyme called VirD2 is attached to a fluorescent-tagged nucleotide sequence.

Drops from the reaction between the complex and RT-RPA product are then added to a lateral flow test strip impregnated with a biotin-recognizing protein called streptavidin on one end and a fluorescent probe-recognizing antibody on the other. If the sample contains SARS-CoV-2 gene sequences, they will have bound to the VirD2-Cas9 complex. A positive result occurs when two visible lines appear. The first line is where biotin on the SARS-CoV-2 amplicon binds to streptavidin. The second line is where the fluorescent tag on the other end of the complex attaches to the strip’s antibody. A negative result shows only as a single line caused by the fluorescent tag binding to the antibody.

“Several types of lateral flow tests are currently available or under research for detecting SARS-CoV-2,” said KAUST Ph.D. student Tin Marsic. “Depending on how they work, they all have disadvantages, including detecting the virus only several days after infection or producing false positive and false negative results. Vigilant can be conducted in non-laboratory settings and is significantly cheaper and easier to use than PCR tests.”

“We’re now working on making our Vigilant platform more user-friendly by coupling it with an even simpler amplification technique,” added KAUST bioengineer Magdy Mahfouz, who led the research. “We are also working on producing other efficient and rapid diagnostic tests that can detect nucleic acids to enable point-of-care testing for pathogens, including viruses and disease markers.”

Related Links:
KAUST


Gold Member
Universal Transport Solution
Puritan®UniTranz-RT
3-Part Differential Hematology Analyzer
Swelab Alfa Plus Sampler
New
Staining System
RAL DIFF-QUIK
New
Drug Test Kit
DrugCheck 3000
Read the full article by registering today, it's FREE! It's Free!
Register now for FREE to LabMedica.com and get access to news and events that shape the world of Clinical Laboratory Medicine.
  • Free digital version edition of LabMedica International sent by email on regular basis
  • Free print version of LabMedica International magazine (available only outside USA and Canada).
  • Free and unlimited access to back issues of LabMedica International in digital format
  • Free LabMedica International Newsletter sent every week containing the latest news
  • Free breaking news sent via email
  • Free access to Events Calendar
  • Free access to LinkXpress new product services
  • REGISTRATION IS FREE AND EASY!
Click here to Register








DIASOURCE (A Biovendor Company)

Channels

Molecular Diagnostics

view channel
Image: The RNA-seq based diagnostic test for pediatric leukemia ensures better outcomes for children with this common cancer (Photo courtesy of Qlucore)

RNA-Seq Based Diagnostic Test Enhances Diagnostic Accuracy of Pediatric Leukemia

A new unique test is set to reshape the way Acute Lymphoblastic Leukemia (BCP-ALL) samples can be analyzed. Qlucore (Lund, Sweden) has launched the first CE-marked RNA-seq based diagnostic test for pediatric... Read more

Hematology

view channel
Image: CitoCBC is the world first cartridge-based CBC to be granted CLIA Waived status by FDA (Photo courtesy of CytoChip)

Disposable Cartridge-Based Test Delivers Rapid and Accurate CBC Results

Complete Blood Count (CBC) is one of the most commonly ordered lab tests, crucial for diagnosing diseases, monitoring therapies, and conducting routine health screenings. However, more than 90% of physician... Read more

Immunology

view channel
Image: A simple blood test could replace surgical biopsies for early detecion of heart transplant rejection (Photo courtesy of Shutterstock)

Blood Test Detects Organ Rejection in Heart Transplant Patients

Following a heart transplant, patients are required to undergo surgical biopsies so that physicians can assess the possibility of organ rejection. Rejection happens when the recipient’s immune system identifies... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.