Researchers at Carnegie Mellon University have developed a microfluidic chip that can provide rapid COVID-19 antibody tests. The electrochemical test can detect very low concentrations of antibodies in blood samples, and transmits the results to a smartphone. The test could help to measure patient responses to vaccines and determine if they have been previously exposed to SARS-CoV-2, the virus responsible for COVID-19.
Antibody tests have their place in our arsenal of weapons in the fight against SARS-CoV-2. Determining who has been exposed to the virus and assessing their immune response after a vaccine means that antibody tests can be very useful. This latest test can provide results extremely rapidly, and with only a small drop of blood.
“We utilized the latest advances in materials and manufacturing such as nanoparticle 3D printing to create a device that rapidly detects COVID-19 antibodies,” said Rahul Panat, a researcher involved in the development of the new device. “Because our technique can quantify the immune response to vaccination, it is very relevant in the current environment.”
The researchers used a technique called aerosol jet nanoparticle 3D printing to create gold micropillar electrodes within the device. The rough surface of the pillars results from the deposition of aerosol droplets that are then thermally sintered together. This surface roughness increases the pillar surface area allowing for enhanced antibody binding to antigens on the electrode surface.
The researchers then coated the electrodes with reduced?graphene?oxide nanoflakes, and immobilized viral antigens on the electrode surface. This allows the electrochemical device to rapidly detect as little as 0.15 nanograms of antibody per mL of blood, although the device requires only one drop of blood to perform a test. The test can identify two antibodies against structures on the virus, including the spike S1 protein and the receptor binding domain.
The test can transmit its results to a generic smartphone and is a platform technology, meaning that it can easily be adapted to detect other viruses in blood samples, including HIV and Ebola.
See a video about the technology below:
Study in Advanced Materials: Sensing of COVID?19 Antibodies in Seconds via Aerosol Jet Nanoprinted Reduced?Graphene?Oxide?Coated 3D Electrodes