Nasal test swabs are increasingly playing an important role in identifying COVID-infected patients, and there is an increased demand for them as global test capacity ramps up resulting in supply shortages.
How Are They Used
These swabs typically come in flexible sticks with a bristled end and are used to collect a sample of secretions from the uppermost part of the throat, behind the nose, during tests of suspected cases for respiratory infections. They are then placed in a test tube where it is then transported into a laboratory for testing.
3D printing has quickly become a thing as it can quickly produce in-demand items like essential healthcare equipment. Our applications team has been hard at work working on applications, and have successfully 3D printed nasal swabs using ULTEM 1010™ CG resin material with Stratasys Fortus 450mc.
But what’s the differential here with ULTEM 1010™ CG? There are a few critical safety considerations when it comes to 3D printing nasal swabs for medical use which ULTEM 1010™ CG has.
Why is it so Critical for those Features?1 Heat Resistance
Before the swab test is carried out, the swab will need to go through a 160°C heat sterilization. With ULTEM 1010™ CG high heat temperature (216°C @ 66 psi), it makes for an ideal material for safety usage. Similarly, the mechanical properties of the 3D printed swab showed no deterioration even after going through autoclave procedures for sterilization.
Most other materials with similar features might lack this critical certification.2 Low Outgassing
Low outgassing means low water absorption.
In every swab test, the swab will be placed in a test tube half-filled with a liquid solution. If a material has a high water absorption rate, the swab will be contaminated and this affects the test result.
In addition, the 3D printed part might react and change, making it unfit for actual use.3 Biocompatible
Certified and safe for human usage.An October 10, 2018 Emergo DOC (Document of Compliance) for ULTEM 1010™ CG states that per the manufacturer (i.e, Stratasys), ULTEM 1010™ CG was capable of gamma and steam sterilization.
You can also review the biocompatibility and sterilizability supporting documentation on the biocompatibility of ULTEM 1010™ CG and other FDM materials that were tested by Stratasys according to standards.
Unique Value Proposition
For mass-produced nasal swabs, the designs are typically not recommended for 3D printing due to their tip “catch design.”
The purpose of this tip is to allow the cotton to be attached to it before the test begins. Our Application Engineer understands this point and through thorough testing, introduces a 2.5mm tip catch that is optimized for 3D printing and is a challenge for any other 3D printers in the market but not so for Stratasys Fortus 450mc.
Typically, nasal swabs are actually quite long due to safety reasons during handling. After the swab is done using the ULTEM 1010™ CG 3D printed swab, it can be broken easily at an intentionally weak point (see red circles) that are a few centimeters from the tip so that the important portion can be placed into the test tube.