Introduction
In medical devices, pharmaceutical manufacturing, and implantable applications, sealing components must do more than prevent leaks—they must also be biocompatible, chemically resistant, and capable of withstanding sterilization.
This article explores the best biocompatible materials, manufacturing processes, and key design considerations for custom medical and pharmaceutical seals.
1. Why Use Custom Biocompatible Seals?
Unlike off-the-shelf seals, custom biocompatible seals are designed for:
- Medical & Pharmaceutical Compliance – Must meet FDA (21 CFR 177.2600), ISO 10993, and USP Class VI standards.
- Chemical & Drug Compatibility – Withstand active pharmaceutical ingredients (APIs), bodily fluids, and sterilization chemicals.
- Precision & Complex Shapes – Micro-molded for catheters, surgical tools, implantable components, and drug delivery systems.
- Extreme Temperature & Sterilization Resistance – Operate under steam autoclave, gamma radiation, and EtO gas sterilization.
Common Applications:
- Implantable Seals – Heart valves, prosthetics, pacemakers.
- Surgical Device Gaskets – Robotic-assisted surgery components.
- Pharmaceutical Seals – Fluid transfer systems, bioprocessing seals.
- Microfluidic Seals – Lab-on-chip devices, diagnostic instruments.
2. Best Biocompatible Materials for Custom Seals
| Material | FDA (21 CFR 177.2600) | ISO 10993 | USP Class VI | Best Applications |
|---|---|---|---|---|
| Silicone (VMQ, LSR) | ✅ Yes | ✅ Yes | ✅ Yes | Implantable seals, drug delivery systems, medical tubing |
| Fluorocarbon (FKM, Viton®) | ✅ Yes | ✅ Yes | ✅ Yes | Pharmaceutical gaskets, sterilizable seals, high-chemical resistance |
| EPDM | ✅ Yes | ⚠️ Limited | ✅ Yes | Autoclave-resistant medical and biopharma seals |
| Polyurethane (PU) | ✅ Yes | ✅ Yes | ✅ Yes | Biomedical implants, prosthetics, soft-tissue seals |
✅ = Fully Compliant | ⚠️ = Requires Specific Grades
Best for Implantable Devices: Medical-Grade Silicone, Polyurethane
- Low extractables, long-term biocompatibility.
- Used in cardiovascular implants, prosthetics, and drug-delivery implants.
Best for Pharmaceutical & Fluid Sealing: Fluorocarbon (FKM), EPDM
- Resistant to active pharmaceutical ingredients (APIs) and high-purity fluids.
- Used in bioreactors, sterile drug manufacturing, and cleanroom environments.
3. Custom Manufacturing Processes for Biocompatible Seals
Injection Molding (Best for High-Precision Seals)
- Used for: Medical-grade O-rings, micro-seals, and complex geometries.
- Materials: Silicone (LSR), FKM, EPDM.
- Why? Provides flash-free, high-tolerance seals for medical and pharmaceutical use.
Transfer Molding (Best for Medium-Volume Custom Seals)
- Used for: Implantable seals, gaskets, diaphragms.
- Materials: Fluorocarbon (FKM), EPDM, Silicone.
- Why? Reduces material waste while offering high-precision molding.
Micro-Molding (Best for Miniature Seals & Lab Equipment)
- Used for: Microfluidic devices, lab-on-chip diagnostics, implantable micro-seals.
- Materials: Silicone, Polyurethane, Fluorocarbon.
- Why? Enables high-precision, burr-free, sub-millimeter sealing solutions.
Key Design Considerations for Biocompatible Custom Seals
1. Optimize for Sterilization & Chemical Exposure
- High-heat applications? Use Silicone (VMQ) or FKM for steam autoclave resistance.
- Harsh chemicals? Use FKM or EPDM for acid and solvent resistance.
2. Precision Tolerances & Flash-Free Molding
- Medical and implantable seals require ultra-tight tolerances (±0.025mm or better).
- Liquid injection molding (LIM) ensures minimal flash and uniform sealing performance.
3. Custom Profiles for Specialized Sealing
- Quad-rings & X-rings: Prevent rolling or twisting in dynamic seals.
- Lip seals & barrier seals: Used in fluid separation and inkjet applications.
- Micro-channels & textured surfaces: Improve adhesion in biomedical implants.
Why Custom Biocompatible Seals Matter
Choosing the right biocompatible custom seal ensures regulatory compliance, chemical resistance, and long-term durability in medical, pharmaceutical, and implantable applications.
Implantable devices: Use ISO 10993-approved Silicone or Polyurethane.
Pharmaceutical fluid seals: Choose USP Class VI Fluorocarbon (FKM) or EPDM.
High-precision manufacturing: Consider injection, transfer, or micro-molding.
In Need of Custom Biocompatible Seals?
For custom biocompatible sealing solutions, consult rubber processing specialists to ensure optimal material selection, regulatory compliance, and performance.
Contact us to learn more.
