With production at an Italian facility that is one of major suppliers of nasal swabs needed for COVID-19 test kits severely impacted by the pandemic, Formlabs, a venture-backed maker of 3D printers, and partners USF Health and Northwell Health Labs have stepped in to meet demand.
In just one week, the teams collaborated to develop a nasal swab prototype and tested it at the USF Health and Northwell Health Labs, diagnostic test labs that are processing COVID-19 test kits. The prototypes were created using Formlabs’ 3D printers and biocompatible autoclavable resins. With clinical validation finalized, 3D printers at all three companies will produce the swabs at throughput rates of up to 300 units per printer per day.
A big design challenge
Nasal swab sticks are typically manufactured using injection molds and flocking, which includes tufts of polyester material attached to the end of a plastic shaft. Two main factories produce these flocked swabs - one in Northern Italy and one in Maine. With supply impacted by the pandemic, healthcare professionals are turning to 3D printed swabs.
Nasal swabs are flexible sticks with a bristled end that is inserted into the nose to the back of the nasal cavity and swept around to collect material that sticks to or wicks up the bristles. The swab is then placed into a vial that contains a culture medium.
A spokesperson for Formlabs explained that swab sticks have an intentionally weak point 7–8 cm from the bristled tip. This design feature allows the stick to be broken to the correct length so that the vial can be capped before it is transported to a laboratory for testing.
“The most difficult part of designing these swabs to be 3D printed was ensuring the material we used was strong enough to be put in a patient's nose without fear of it breaking and yet weak enough that it can be easily capped and put in a vile,” said Formlabs. “The swab also has to be capable of collecting enough of a sample from the nasal cavity to detect virality without hurting the patient.”
A single 3D print run can produce up to 300 test swabs at a time. “With 200+ in-house 3D printers at our Ohio-based, FDA-registered ISO 13485 printing facility is now dedicated to producing COVID-19 test swabs,” said Formlabs, “With the potential to ramp up production to about 100,000 printed swabs a day at peak.”
Formlabs is reaching out to the tech and medical community to connect those with equipment and supply needs with companies and individuals who can provide engineering, clinical, and 3D printing resources. They are asking anyone working on COVID-19 related projects and need access to 3D printed parts, or who have access to 3D printers and are willing to volunteer time and equipment in the fight against COVID-19, to complete this form.
It notes that the swabs are Class I medical devices, as per the FDA’s Policy for Diagnostic Tests for COVID-19, and are exempted from premarket notification requirements and require manufacturers to register and list the products.