Carnegie Mellon pioneers 3D printed sensor that detects COVID-19 antibodies in seconds

A new COVID-19 antibody detection device developed by researchers at Carnegie Mellon University, capable of identifying the antibodies within 10 to 15 seconds, is now entering a trial stage with COVID patients. The innovative system consists of a low-cost sensor made up of tiny gold electrodes 3D printed using Optomec’s Aerosol Jet technology.

The device, if approved for broad usage, could become another vital tool in medical professionals’ toolbelt against COVID-19. With it, clinicians could instantly detect COVID-19 antibodies in patients, which could provide a deeper understanding of how the virus is spreading and a better chance of controlling it. Moreover, it is cheap to produce—reportedly in the tens of dollars.

The 3D printed sensor works thanks to a specific geometry and surface characteristics, which were developed by Rahul Panat, Associate Professor of Mechanical Engineering at Carnegie Mellon University, and his team. Panat specializes in the use of AM for producing biosensing devices and human-computer interfaces.

“My research team was working on 3D printed high-performance sensors to detect dopamine, a chemical in the brain, when we realized that we could adapt our work for COVID-19 testing,” he explained. “We shifted our research to apply our expertise to combatting this devastating pandemic. The Aerosol Jet process was critical to producing a sensor with high sensitivity and speed.”

The 3D printed sensor is designed to identify SARS-CoV-2 antibodies, even at very low concentrations. Essentially, a very small drop of blood from a fingertip is placed on the sensor, which triggers an electrochemical reaction that detects spike S1 protein and receptor binding domain (RBD), two COVID-19 antibodies. The 3D printed sensor is embedded into a simple handheld microfluidic device, which is connected to a smartphone through an easy-to-use interface. The sensor can then be quickly cleaned (within a minute) using a special chemistry and can be reused.

Optomec’s Aerosol Jet technology was vital to the sensor’s development. Capable of printing highly precise conductive and non-conductive materials with features as fine as 10 microns, the process prints tiny aerosol droplets which are subsequently sintered. In this case, the process is used to 3D print 100 nanoscale gold micropillar electrodes within a 2mm square. This results in a sensor with an irregular texture, which creates an “increased surface area of the micropillars and an enhanced electrochemical reaction, where antibodies can latch on to antigens coated on the electrode.” The sensor’s unique geometry enables the sensor to contain more proteins for detection, resulting in fast and accurate results.

Presently, the Carnegie Mellon University research team is also working to adapt the device to detect the active virus in patients, which could streamline the testing process dramatically. It could also be used to detect other types of virus, including Zika, Ebola and HIV. Panat added: “This sensing platform can also be used to detect other infectious diseases, potentially affecting the course of pandemics.”