Electronics Integration Impacting Medtech Materials

Materials science has played a key role in the global battle against COVID-19.
 
Triiodide, salt, copper, nano-silver, polyimide, and graphene are just a few of the recruits drafted thus far in the 18-month coronavirus war. Sodium chloride, a natural anti-bacterial agent, is adept at filtering air and decontaminating surfaces, while copper “foam” can effectively capture tiny aerosol droplets carrying virus particles (diameters between 0.1 and 0.4 micrometers). Moreover, graphene has been used as a protective coating on face masks (the material’s sharp edges damage viruses), and Vyon porous plastic filters are helping a University of Cambridge (U.K.) spinout company diagnose COVID-19 infections in less than 90 minutes.
 
A research team at Northeastern University, meanwhile, has adopted a virus “mentality” to defeat SARS-CoV-2. The institution’s “Nano-Medicine Lab” created an injectable nano-molecular material that could prevent bacterial infection spread and also help reduce inflammation.
 
“What we are creating in the lab are molecules that are about 80,000 times smaller than the diameter of a strand of your hair,” Thomas Webster, the lab’s head, said in an interview posted on the school’s website. “In order to kill the viruses, you have to make a nano-meter material to disrupt their function.”
 
The technology Webster’s lab is researching as a potential coronavirus weapon actually was developed eight years ago as an injectable to help regenerate tissue and cartilage. The material was licensed by Concord, Mass.-based Audax Medical Inc. and has been commercialized for several regenerative medicine applications.
 
“We quickly hypothesized, when this COVID-19 situation came up,” Webster explained, “that these molecules are great at healing tissue, they’re great at reducing infections, exceptional at inhibiting inflammation that often comes from microbes, and perhaps it could be used to kill viruses.”
 
Such hypotheses were not uncommon over the last year as scientists, virologists, and medical professionals frantically searched for COVID-19’s molecular Achilles Heel. The pandemic, in fact, underscored the importance of materials science in developing tools and technologies for anti-viral research and treatment.
 
MPO’s March feature, Resourceful Resources, details the various pandemic response efforts of more than a half-dozen materials suppliers and manufacturers. The story also examines the challenges associated with developing wearable materials, and the impact AI and digital health has had on the space. Lars Gerding, vice president of Technology at Freudenberg Medical, was among the experts interviewed for the story. His full input is provided in the following Q&A.
 
Michael Barbella: In what ways has the global pandemic spurred material innovation?
Lars Gerding: I don’t think it affected our space too much. We saw more innovation in the design of devices/components like face shields, masks, ventilators, and test kits. Material innovation would be more prevalent for filter media (such as face masks), nonwovens and media to make masks more efficient (breathable vs. absorbing)
 
Barbella: Organizations from outside the medtech industry pitched in at the start of the pandemic to help address the shortage of ventilators and PPE. What kind of impact did that have on the kinds of materials used for those products? Was/is there more flexibility with regard to the types of materials used for ventilators and PPE?
Gerding: My observation is that companies outside of medtech do not have too much experience with medical grade materials, where these materials are required, where a standard material could be used over a specialty polymer, and what materials can be used when a specific sterilization method is required.
 
Barbella: What material challenges are associated with developing wearable products and how can these hurdles be overcome?
Gerding: Skin sensitivity, with sensors on the body, is a development challenge for wearables. They need to be sticky enough not to fall off but easy to remove, and sometimes the sensor may need to be reusable. A device may also need sensor integration/electrification.
 
Barbella: How is digital health and AI impacting the development of medical device materials? Has it changed the kind of materials developed/used in devices?
Gerding: Electrification in general has an impact on medical devices, e.g., by integration of electronics into devices or by enhancing components with electrical properties. Conductive materials would be an example of such. Electrification can also create a demand for EMI shielding which can be accomplished by modifying polymers or applying coatings.
 
Barbella: With the growing importance of sustainability and recyclability in the industry, can medtech materials be made more sustainable? If so, how?
Gerding: I think it is a missed opportunity that we cannot recycle material in the medical industry. But the waste that we generate can be recycled and Freudenberg is proactive about recycling. Our scrap is from a cleanroom environment, it’s clean, one polymer, and not a mix of several materials so it’s good for recycling companies. Our scrap is always from virgin material, it’s premium waste and can be recycled. Medical devices are primarily single-use but Freudenberg is supporting some initiatives to design devices that can be more easily reprocessed—enabling customers to venture down this path.
 
Barbella: Please discuss an instance (example) of an innovative material solution(s) your company came up with to meet challenging customer requests.
Gerding: Material substitution in general is a big topic for the medical industry, whether it is switching from stainless steel to high performance polymers or from special rubber formulations to standard silicones. In catheter systems the compound for the extrusion can be very challenging. Usually, we deal with highly filled polymers that require anti-oxidants and stabilizers in order not to break down during processing and more delicately during accelerated aging. This means you don’t really see proof of a working recipe until these aging tests are finished, most commonly one of the last steps in device development. A lack of stabilizers could result in device failure while overloaded compounds tend to show a blooming effect of the additives. There is a delicate balance of the right recipe with the right accelerated aging parameters to lead to success.