MedTech Polymers

Plenary Session: Opening Keynote Speech

Is there room for innovation in today's medical device industry?

Stanton Rowe
Corporate Vice President, Advanced Technology and Chief Scientific Officer
Edwards Lifesciences >More

Opening Remarks

Chair: Vipul Davé, Engineering Fellow - MD&D Global Supply Chain, Johnson & Johnson

Suture and fiber materials selections for cardiovascular device components

Suture and fiber technology has a fundamental impact on the performance and viability of the next generation of cardiovascular devices. Specialized fibers and sutures with greater variability of properties and performance characteristics have enabled device innovations to maximize overall device performance. The challenge to designers is to balance a complex combination of mechanical, physical, and biological response properties to ensure cost-effective manufacturing of a device, and its effective, reliable use.

This presentation explores some of the important factors to consider when selecting the right suture and fiber technologies to solve the requirements of a cardiovascular device design and the assembly of products such as heart valves or endovascular stent grafts. The attendee will come away with an understanding of:

• Different fiber and material technologies and their impact on performance characteristics
• Selection of the correct color and size choices to meet requirements of an application
• Suture design consideration when designing a device:
• Monofilament versus multifilament
• Braid versus coreless braids

Ed Boarini, Sr. VP and General Manager, Teleflex Medical

Using Polymers’ Mechanical and Surface Properties in the Development of Stem Cell-Based Tissue Engineering Therapies

The tissue engineering field is constantly developing new strategies to address the repair and restoration of natural tissues. Within the tissues, the extracellular matrix (ECM) is composed of many complex compounds that transfer chemical and mechanical stimuli to proximal cells. Several tissue engineering therapies implement extracellular matrix-derived “scaffolding” constructs, into which cells are seeded before or after implantation. Therefore, advances in scaffold-based therapies depend on an understanding of the cells’ behavior in response to the scaffolds’ physical and chemical structure.

The role of stem cells in tissue engineering is of increasing importance, and control of terminal differentiation prior to implantation remains a primary goal for stem cell scientists. Because stem cells’ differentiation can be affected by the ECM’s mechanical properties and microstructure topology, researchers have used customized synthetic polymers to mimic aspects of those properties before introducing the cells to the polymers. Subsequent stem cell behavior is observed in route to future applications of stem cell-based therapies.

This presentation will focus on how various polymers, and associated microfabrication techniques, have been used to construct scaffolds with specific physical and surface properties in order to learn more about stem cell behavior. An added focus will be placed upon the techniques used to characterize these customized polymers prior to stem cell introduction.

Byron Deorosan, Associate, Exponent

Meeting the Demands of Medical Device Performance Requirements with Polymeric Bioresorbable Vascular Scaffolds

The fourth revolution in interventional cardiology is upon us – the device industry is raising the bar. No longer is the end desire simply to open a vascular lumen to restore blood flow, secure dissected tissue with a stent, or prevent late stage stent thrombosis.  The new era demands all that functionality be done using a temporary structure, a Bioresorbable Vascular Scaffold (BVS), which then resorbs into the body.  The vessel is thereby restored to an unscaffolded state for which natural vasoactivity (e.g., contraction and dilation with blood pressure) is possible.  The transitory nature of the scaffold requires that time-dependent mechanical property requirements be established.  How much strength is required of the scaffold to provided adequate vessel support and for how long?  Meeting these demands using a polymeric BVS presents technical challenges relating to microstructural properties, macroscopic material properties, and device response.

This presentation will outline the performance requirements of the Abbott Vascular Absorb™ BVS, how polymer processing impacts both microstructural and macroscopic material properties, how these properties are realized by the device in positive clinical results, and what future BVS opportunities exist.

This presentation is funded by Abbott Vascular.

Ashley Kelley, Sr. R&D Engineer, Abbott Vascular

EFEP co-extrusion technology

New fluoropolymer materials have been developed and allow co-extrusions with PEBA and Nylon-Based polymers to provide a robust and cost effective solution to traditional catheter manufacturing. These constructions can be achieved without the need of a tie layer to bond the dissimilar materials together.

Traditional catheter manufacturing that uses fluoropolymers is a time consuming, labor intensive process. Sadly, the results are often not reliable. This material/technology combination changes that. Catheters can now be manufactured more cost-effectively and more reliably without concern over delamination of the layers. EFEP works best with specialty grades of PEBA, and other Nylon based materials.

This presentation will help you understand the benefits of EFEP co-extrusion technology:

• Co-Extrusion vs. hand built catheters
• High degree of automation
• No delamination of tubing
• No toxic chemical etching required
• High reliability
• Improved vascular access - small diameter tubing (~5 French) is possible

John Felton, Market Development Manager, Daikin America

Advances in antimicrobial plastics technology

Nosocomial infections are an increasing problem in the hospital and health care environment, especially with the growth of antibiotic resistant strains of microbes such as Methicillin-resistant Staph. aureus (MRSA) and Vancomycin-resistant Enterococcus (VRE).  Through “bundling” of interventions, hospitals are taking a multi-front approach to attacking this problem.  Thus, to address catheter related infections a bundle would include hand hygiene, daily assessment of catheter necessity, aseptic technique, etc.   Included in this could be the use of devices or protective equipment fashioned from antimicrobial materials.  Typically, these materials are made antimicrobial by incorporation of an antimicrobial agent into a polymer matrix prior to final fabrication, or added after fabrication in a coating process.   In this session, we will discuss some advances in the use of antimicrobial agents in several medical applications.  These will include examples in nonwoven fabrics as well as rigid, polymeric materials such as clear styrenic polymers or engineering plastics, such as polyamides, for structural applications.

Matthew Gande, Principal Technology Specialist, BASF

Comparative radiopacity and mechanical properties of FDA compliant radiopacifiers

Radiopacifiers allow the medical device to be visualized under radiography and fluoroscopy. However it is the type of Radiopacifier that affects the loading in the polymer and thus mechanical properties. Further, Radiopacifier X-Ray efficiency (intensity/g under X-Ray) is influenced by:

• Nature of the radiation
• Density
• Atomic number
• Electrons per gram of the radiopaque material

This study will compare the most used medical radiopacifiers in terms of X-Ray efficiency and their effect on polymer mechanical properties.

Jack Frautschi, Sr. Biomaterials Scientist, PolyOne Corporation

MEMS intraocular drug delivery device

Ronalee Mann, Senior Associate, Exponent

Chemical resistance of Eastman Tritan™ copolyesters and engineering polymers used in medical devices - oncology drug case study

Currently, there are demanding needs for plastics used in medical and pharmaceutical applications to meet the desired physical, environmental, and efficacy requirements of the next generation medical devices and cancer drugs. Meeting chemical resistance, drug compatibility and dynamic performance levels needs demand better performing engineering materials. Eastman’s family of copolyesters offer significant advantages for numerous medical applications due to their excellent optical clarity, toughness, superior color stability when exposed to a variety of sterilization techniques, and chemical resistance. Chemical resistance is a key concern for materials used in medical applications. Environmental stress cracking (ESC) is the most important mechanism for thermoplastics used in medical devices. A comprehensive understanding of Tritan™ copolyesters oncology drug chemical resistance and ESC will provide us insights of finding their success in the emerging chemotherapy market. In this presentation, the chemical resistance and mechanical properties of Eastman Tritan™ copolyesters and other common engineering polymers used in medical devices are evaluated using a series of representative oncology drugs which are widely used in current medical application. Testing protocols to evaluate the different facets of chemical resistance and mechanical property will also be discussed.

Yubiao Liu, Medical Application Development Manager, Eastman Chemical