Chip simplifies COVID-19 testing, delivers results on a phone

Programmed magnetic nanobeads enable diagnostic device designed at Rice University
26-Feb-2021 12:25 PM EST, by Rice University

Newswise — HOUSTON - (Feb. 25, 2021) - COVID-19 can be diagnosed in 55 minutes or less with the help of programmed magnetic nanobeads and a diagnostic tool that plugs into an off-the-shelf cell phone, according to Rice University engineers.

The Rice lab of mechanical engineer Peter Lillehoj has developed a stamp-sized microfluidic chip that measures the concentration of SARS-CoV-2 nucleocapsid (N) protein in blood serum from a standard finger prick. The nanobeads bind to SARS-CoV-2 N protein, a biomarker for COVID-19, in the chip and transport it to an electrochemical sensor that detects minute amounts of the biomarker.

The researchers argued their process simplifies sample handling compared to swab-based PCR tests that are widely used to diagnose COVID-19 and need to be analyzed in a laboratory.

"What's great about this device is that doesn't require a laboratory," Lillehoj said. "You can perform the entire test and generate the results at the collection site, health clinic or even a pharmacy. The entire system is easily transportable and easy to use."

The research appears in the American Chemical Society journal ACS Sensors.

Lillehoj and Rice graduate student and lead author Jiran Li took advantage of existing biosensing tools and combined them with their own experience in developing simple diagnostics, like a microneedle patch introduced last year to diagnose malaria.

The new tool relies on a slightly more complex detection scheme but delivers accurate, quantitative results in a short amount of time. To test the device, the lab relied on donated serum samples from people who were healthy and others who were COVID-19-positive.

Lillehoj said a longer incubation yields more accurate results when using whole serum. The lab found that 55 minutes was an optimum amount of time for the microchip to sense SARS-CoV-2 N protein at concentrations as low as 50 picograms (billionths of a gram) per milliliter in whole serum. The microchip could detect N protein in even lower concentrations, at 10 picograms per milliliter, in only 25 minutes by diluting the serum fivefold.

Paired with a Google Pixel 2 phone and a plug-in potentiostat, it was able to deliver a positive diagnosis with a concentration as low as 230 picograms for whole serum.

"There are standard procedures to modify the beads with an antibody that targets a particular biomarker," Lillehoj said. "When you combine them with a sample containing the biomarker, in this case SARS-CoV-2 N protein, they bond together."

A capillary tube is used to deliver the sample to the chip, which is then placed on a magnet that pulls the beads toward an electrochemical sensor coated with capture antibodies. The beads bind to the capture antibodies and generate a current proportional to the concentration of biomarker in the sample.

The potentiostat reads that current and sends a signal to its phone app. If there are no COVID-19 biomarkers, the beads do not bind to the sensor and get washed away inside the chip.

Lillehoj said it would not be difficult for industry to manufacture the microfluidic chips or to adapt them to new COVID-19 strains if and when that becomes necessary.

###

SEE ORIGINAL STUDY



Filters close

Showing results

110 of 6084
Newswise: Public
Released: 28-Jul-2021 2:45 PM EDT
Highly Potent, Stable Nanobodies Stop SARS-CoV-2
Max Planck Society (Max-Planck-Gesellschaft)

Göttingen researchers have developed mini-antibodies that efficiently block the coronavirus SARS-CoV-2 and its dangerous new variants.

Newswise: Public
Released: 28-Jul-2021 2:20 PM EDT
Psychological Consequences of COVID-19 in Health Care
University of Bonn

Physicians, nursing staff, medical technical assistants, and pastoral workers in hospitals: they have all been placed under severe strain by the Covid-19 pandemic.

Newswise: Public
Released: 28-Jul-2021 2:10 PM EDT
Why Lockdown in Africa Does Not Work as a First COVID-19 Pandemic Response
University of Johannesburg

In an African pandemic it is more productive to consider lockdowns, after using other non-medical measures first, Especially in countries with high levels of poverty and corruption, says Prof Nicholas Ngepah, a Professor of Economics at the University of Johannesburg in South Africa.

Newswise:Video Embedded how-to-talk-with-people-who-are-not-vaccinated-against-covid-19
VIDEO
Released: 28-Jul-2021 1:40 PM EDT
How to Talk With People Who Are Not Vaccinated Against COVID-19
Cedars-Sinai

Even though she has asthma, putting her at higher risk for severe complications from COVID-19, Angela Reeves-Flores, 33, waited until a week ago to get vaccinated.

Newswise: Indian Women’s Nutrition Suffered During COVID-19 Lockdown
Released: 28-Jul-2021 12:50 PM EDT
Indian Women’s Nutrition Suffered During COVID-19 Lockdown
Cornell University

A new study from Cornell University finds the nationwide lockdown India imposed last year in response to COVID-19 caused disruptions that negatively impacted women’s nutrition.

Released: 28-Jul-2021 12:00 PM EDT
MD Anderson Research Highlights for July 28, 2021
University of Texas M. D. Anderson Cancer Center

The University of Texas MD Anderson Cancer Center’s Research Highlights provides a glimpse into recently published studies in basic, translational and clinical cancer research from MD Anderson experts. Current advances include a newly discovered protein that controls B cell survival, understanding epigenetic changes in malignant peripheral nerve sheath tumors (MPNSTs) and melanoma, identifying a protein that protect genome stability, developing novel cell therapies for COVID-19, a new option for treating neuropathic pain, exosome delivery of CRISPR/Cas9 to pancreatic cancer, discovering how cancer cells tolerate aneuploidy and the role of health disparities in long-term survival of adolescent and young adult patients with Hodgkin lymphoma.

Released: 28-Jul-2021 11:30 AM EDT
Study Reveals Characteristics of SARS-CoV-2 Spike Protein
University of Kentucky

A new University of Kentucky College of Medicine study published in the Journal of Biological Chemistry provides foundational information about SARS-CoV-2’s spike protein.

access_time Embargo lifts in 2 days
Embargo will expire: 4-Aug-2021 9:00 AM EDT Released to reporters: 28-Jul-2021 11:15 AM EDT

A reporter's PressPass is required to access this story until the embargo expires on 4-Aug-2021 9:00 AM EDT The Newswise PressPass gives verified journalists access to embargoed stories. Please log in to complete a presspass application. If you have not yet registered, please Register. When you fill out the registration form, please identify yourself as a reporter in order to advance to the presspass application form.

Newswise: UIC Awarded $6 Million to Develop Potential COVID-19 Treatment
Released: 28-Jul-2021 10:15 AM EDT
UIC Awarded $6 Million to Develop Potential COVID-19 Treatment
University of Illinois Chicago

Researchers at the University of Illinois Chicago are developing a potential treatment for COVID-19, thanks to a $6 million technology and therapeutic development award from the U.S. Department of Defense supporting pre-clinical animal studies.

Newswise: Don’t Let the Raging Virus Put Life in Jeopardy. Chula Recommends How to Build an Immunity for Your Heart Against Stress and Depression
Released: 28-Jul-2021 8:55 AM EDT
Don’t Let the Raging Virus Put Life in Jeopardy. Chula Recommends How to Build an Immunity for Your Heart Against Stress and Depression
Chulalongkorn University

Cumulative stress, denial, and chronic depression are the byproducts of the COVID-19 pandemic. The Center for Psychological Wellness, Chulalongkorn University recommends ways to cope by harnessing positive energy from our heart.


Showing results

110 of 6084

close
2.00487