Drug Delivery Devices, Wearables Driving Materials Innovation

Bye bye, bacteria.
 
Scientists have developed a promising new weapon in the war against hospital-acquired infections. UCLA specialists are fine-tuning an anti-microbial barrier they created for implantable medical devices using zwitterionic material and ultraviolet light. Zwitterionic substances are comprised of molecules that possess an equal amount of cationic and anionic groups, thereby rendering them electrically neutral.
  
The UCLA team built the barrier by depositing a thin layer of zwitterionic material to a device surface and then bonding it to the underlying substrate through UV light irradiation. Early clin- ical results are encouraging—laboratory testing shows the surface treatment reduces biofilm growth by more than 80% and in some cases up to 93%, depending on the bacterial strain.
  
“The modified surfaces exhibited robust resistance against microorganisms and proteins, which is precisely what we sought to achieve,” Richard Kaner, a UCLA Dr. Myung Ki Hong professor of Materials Innovation, and senior research author, told the university’s news service earlier this year. “The surfaces greatly reduced or even prevented biofilm formation. Our early clinical results have been outstanding.”
  
Those results are based on 16 long-term urinary catheter users who switched to silicone devices containing the zwitterionic surface treatment. The modified catheter is the first product made by SILQ Technologies Corp., a UCLA spinout company Kaner founded out of his lab in April 2020. The catheter has been cleared for use by the U.S. Food and Drug Administration.
  
Materials science is key to medtech innovation. New and improved manufacturing materials have led to advancements such as bioprinting, skin-friendly adhesives, shape memory plastics, bioactive glass (orthopedic repair), and bioresorbable stents.
  
MPO’s materials feature examines the latest trends and challenges in medtech materials science, as well as the factors driving innovation in this field. Charles Deleuze, Business Manager for Life Science, Omniseal Solutions (a Saint Gobain business), was among the experts interviewed for this story; his full input is provided in the following Q&A:  
 
Michael Barbella: What are the latest trends in medical device materials? What factors are driving these trends?
Charles Deleuze: An increase in handheld devices that are looking more to plastics to be lightweight and minimally invasive. So, both materials and manufacturing processes are key in the decision of the correct materials to be used. We have materials such as composite materials that are both lightweight and high mechanical strength and wear resistance. Also, an array of fluoropolymers that offer similar properties for friction and wear. Drug delivery devices and wearables are a growing market trend and we’re  working to create new products and testing materials that are cost-efficient for disposable use and for long life capability. These materials protect internal components and are chemical resistant.
 
Barbella: What factors are driving innovation in medical device materials science?
Deleuze: There are primarily two factors driving innovations—miniaturization and longer life or use. This is due to more minimally invasive motors and pumps along with handheld devices, and equipment improvements for customer maintenance and use. An example of customer maintenance and use is longer lifecycle for testing pharmaceuticals purification in liquid chromatography and increase in-vitro diagnostic equipment testing volumes and automation.
 
Barbella: How have adhesive medical materials evolved with the significant growth in medical wearables in recent years?
Deleuze: We have materials that are self-lubricating thermoplastics that can be manufactured in different shapes and eliminate oil or grease requirements. Some of our products are used in surgical tools, including vanes in pneumatic motors and bearings both lightweight and self-lubricating properties. We also have a division that offers adhesives we can work together to create wearable products.
 
Barbella: What material challenges are associated with medical device miniaturization and how can these challenges be overcome?
Deleuze: How the materials are manufactured and depending upon the environment in some instances, makes the decision on the material choice. It also makes a difference on the space constraints for material and product design. Some of the environment needs include wear and friction for duration of the product use, fluid or chemical resistance, amount of pressure, and mechanical operation of the application.
 
Barbella: How have materials suppliers managed the supply chain challenges prompted by the pandemic, and what lessons (changes) might they implement going forward to avoid future problems/issues?
Deleuze: Difficult to have understood the magnitude of supply chain timeliness and inflationary pricing. Working more closely with our customers to manage annual demand forecasts has become crucial for continued on-time delivery of products. Supply chain both customers and our management have increased inventory to manage demand and continue to source in advance. 
 
Barbella: In what ways has the COVID-19 pandemic spurred medical materials innovation, if at all?
Deleuze: Omniseal Solutions provides piston cup seals for respiratory devices and pumps, so there’s been an increase in demand for the cup seals and enhanced materials for longer life, particularly in portable oxygen concentrators. We’re testing new materials with customer products and input.
 
Barbella: How can materials help improve and/or achieve medical device sustainability?
Deleuze: Sustainable materials for eco-friendly products. Saint-Gobain as an organization is working on approaches and tools to design these products on a global basis. Innovate materials and products to reach improved sustainability.  
 
Barbella: Please discuss an instance (example) of an innovative material solution your company came up with to meet a challenging customer request.
Deleuze: Omniseal Solutions provides engineering resources for testing and finite element analysis to create materials that withstand unique environments for lifetime confidence. Many of our customers require 1 million plus lifecycles and our products need to withstand and improve equipment maintenance. We create and test material solutions for the right combination to reach our customers’ goals. Tested wear pad material for improved in-vitro diagnostic carousel advancement, miniature seals, materials for higher pressures in liquid chromatography pumps, and improved manufacturing and materials for drug delivery devices.
 
Barbella: How will medical materials science evolve over the next five years?

Deleuze: Products designed for sustainability and reduced carbon emissions from manufacturing processes. 

• 3D printing materials will expand as the growth in rapid prototyping and production requirements.  
• Printers will increase capacity production so materials will need to accommodate. 
• Surgical robotics automation needs may require more self-lubricious and stronger wear materials.
• Polymer and composite-based products may provide improved maneuverability over incumbent materials to reach hard to access areas of the anatomy during surgery.
• Providing enhanced protection and housing to electronics and sensitive structures during the sterilization process.
• Possibly lessen the need for covering robotics during surgical procedures by improving sterilization options.
• Engineered polymers to reduce the cost of robotic systems through design and architecture change.  
• Movement from metal products to engineered plastics for lightweight and smaller devices as already seen in smaller motors.