The Complete Guide to Engineering Plastic Material Selection for Medical Devices
Medical Device Material Selection Is Different
Selecting a polymer for a medical device involves constraints that do not exist in industrial applications: biocompatibility (ISO 10993), sterilization compatibility (autoclave, EtO, gamma, hydrogen peroxide plasma), FDA master file availability, and traceability requirements. A polymer that performs perfectly mechanically can fail qualification because the supplier will not provide the necessary regulatory documentation.
Sterilization Compatibility Matrix
| Polymer | Autoclave 134C | EtO | Gamma 25kGy | H2O2 Plasma |
|---|---|---|---|---|
| PEEK | Excellent | Excellent | Excellent | Good |
| Ultem PEI | Good | Excellent | Good | Good |
| PPSU Radel | Excellent | Excellent | Fair | Excellent |
| PSU Udel | Good | Excellent | Fair | Good |
Regulatory Pathway
For FDA Class II devices: the polymer must have either a Drug Master File (DMF) or be listed in FDA's approved materials database. For implantables (Class III): ISO 10993-1 biological evaluation is mandatory — cytotoxicity (Part 5), sensitization (Part 10), and systemic toxicity (Part 11) at minimum. Always confirm with the resin supplier that the specific grade you are specifying has the required regulatory documentation before committing to tooling — changing grades mid-project can invalidate biocompatibility data.
References & Industry Standards
- ASTM International. Standard Specifications for Engineering Plastics & Thermoplastics. astm.org
- ISO. ISO 1043 — Plastics — Symbols and Abbreviated Terms. iso.org
- National Institute of Standards and Technology (NIST). Polymer Properties Database. nist.gov
- UL Prospector. Plastics & Elastomers Material Database. ulprospector.com
- MatWeb — Material Property Data. matweb.com