3D printing has already proved useful in the mass production of nasal swabs for COVID-19 testing, but now a team from the School of Engineering at the University of Wolverhampton has taken the medical devices to the next level. In short, it has developed a 3D printed smart swab that can self-adjust to make the awkward swabbing process more comfortable for the patient.
At this point, millions of people around the world will have experienced the painful or at best tingly sensation of having a six-inch plastic swab shoved up their noses. This is because, to date, nasopharyngeal swabbing is the most prevalent form of testing for COVID-19. This new self-adjusting nasal swab design could mitigate the discomfort of the testing process by essentially shrinking to better fit the patient’s nasal cavity.
The 3D printed swab was pioneered by Dr. Arun Arjunan, John Robinson, Dr Ahmad Baroutaji and Suhaib Zahid, who leveraged mechanical meta-material concepts to come up with the smart design. In the simplest terms, the 3D printed swab is designed to contract as it navigates the nasal cavity, causing less stress on the tissues inside the nose.
“This research is the first step in starting an open and collaborative process to drastically improve the existing concepts in nasopharyngeal swabs using the principles of digital fabrication and meta-materials,” explained Dr. Arjunan, a reader in Additive Manufacturing of Functional Materials. “The opportunity to digitally conceive and 3D print swabs allows for the incorporation of geometrical features that can potentially reduce patient discomfort.
“In this regard, our research expertise in additive manufacturing and meta-materials led to the development of auxetic nasopharyngeal swabs that can shrink under axial resistance. This allows the swab to navigate through the nasal cavity with significantly less stress on the surrounding tissues. In comparison, a traditional material will tend to expand under axial load causing discomfort and stress in surrounding tissues.”
At this stage, the research team has 3D printed test samples of the self-adjusting nasal swab in partnership with Formlabs GmbH—which also worked with the University of South Florida (USF), Tampa General Hospital and NY-based hospital system Northwell Health early on in the pandemic to design and mass manufacture nasal swabs in the midst of a severe shortage. The University of Wolverhampton team has also validated the concept at the laboratory scale and is preparing for extensive mechanical and biological characterization of the swab to ensure safety. Data from these tests will be used to enhance the swab design even more and improve its printability for mass production.
“This will be followed by real-world testing of swab collection which will be in collaboration with healthcare partners,” added Dr. Arjunan. “The study is likely to take another six months before it can be used in test centres, however the benefits of the swab go beyond the COVID crisis as these smart swabs are superior to traditional swabs because they significantly reduce patient discomfort and can be printed on demand.”
To ensure that as many people as possible benefit from its research, the team says it will make the design and all accompanying data publicly available, so that once the smart nasal swabs are approved they can be produced anywhere and on demand.