PTFE Liners and Tubing Applications for Medical Devices

PTFE (Polytetrafluoroethylene) is a popular choice for medical device liners. It has been used in devices like catheters for over more than three decades due to its non-stick behavior and a very low coefficient of friction. The material creates smooth passage for medical fluids and medical devices to ensure safe, minimally invasive procedures.

PTFE liners are categorized by their manufacturing process. For example Hydromer®, Inc., uses advanced free extrusion and film-casting methods to produce ultra-thin-wall PTFE linings and tubing. These products are ideal for catheters, delivery systems, and a range of invasive devices that demand enhanced stability and precise device control during procedures.

In this article, we will dive deep into PTFE liners and tubing applications for medical devices. Our goal is to understand the role of PTFE-based liner and tubing products in a range of invasive procedures. If you are a bio-medical or medical device engineer, you will not want to miss how these products can enhance the performance and reliability of your interventional devices, like catheters and guidewires.

What is PTFE?

PTFE (Polytetrafluoroethylene), widely known as Teflon™, is a synthetic polymer composed of carbon-fluorine bonds. Its key properties include non-stick behavior, thermal stability, and chemical inertness. These qualities make PTFE widely used across several industries, including automotive, aviation, and medical sectors.

PTFE’s low coefficient of friction and excellent lubricity make it a preferred material for medical devices. The material is commonly applied as a coating. It is also used in the form of tubing as well as liner within devices such as catheters.

If you are interested in PTFE coatings for medical devices you can learn more in our article titled Intro to PTFE Coatings for Medical Devices – Benefits, Drawbacks, & Alternatives.

Introduction: PTFE Liners vs. PTFE Tubing Products

While related, PTFE tubing is a broad category of PTFE products that includes both specialized and general-purpose tubes, such as heat shrink tubing, mini tubing, and multi-lumen tubing.

PTFE liners, such as MatrixLiner® mini tubing by Hydromer®, are specialized tubes placed inside catheters or device shafts. The primary function of liners is to create a smooth internal lumen, enhancing delivery and device tracking.

Both the PTFE liners and tubing products are manufactured using advanced processes such as the ram or paste extrusion, etching, and sintering. Product selection depends upon the application requirements.

Key Properties of PTFE Lining and Tubing for Medical Device Applications

Polytetrafluoroethylene offers several valuable properties that are extremely beneficial for medical applications, including:

• Excellent Lubricity: PTFE’s low coefficient of friction and surface energy prevent sticking to other materials, resulting in highly lubricious surfaces. This ensures smooth insertion and navigation of devices.
• Thermal Stability: Withstands high temperatures, maintaining integrity and functionality during manufacturing, operation, and sterilization.
• Chemical Resistance: The material resists strong acids, bases, organic solvents, oxidizing agents, and prolonged exposure to biological fluids.
• Biocompatibility: It is non-toxic, non-carcinogenic, and triggers minimal immune response, making it highly suitable for medical use.
• Electrical Insulation: PTFE heat shrink tubing provides excellent electrical insulation for implants, sensors, and electronic instruments.
• Mechanical Stability: PTFE liners offer high flexibility for navigation and maintain stable lumen dimensions even after repeated use.
• Flow Efficiency: Low-friction properties of PTFE tubing and liners improve fluid dynamics, enabling precise dosing and accurate fluid delivery.
• Long-Term Durability: It can withstand repeated flexing and dynamic movement without loss of function.

PTFE Liners and Tubing Applications

PTFE is the preferred material for low-friction tubing and liners products in medical applications. At Hydromer®, we use film-casting and RAM extrusion to produce thin-walled PTFE tubings, setting the standard for liners and tubing with excellent drainage, low friction, chemical resistance, and biocompatibility.

Below are some of the most common applications of Hydromer® PTFE liners and tubings for medical applications:

1. Catheters

Catheters are one of the most common applications for PTFE liners and tubing.

PTFE liners are essential to catheter performance. Most minimally invasive catheters now feature integrated PTFE liners to create smooth inner lumens. This helps ensure safe device movement and fluid flow.

A quick list of catheters that may use PTFE liners or tubings is as follows:

• Gastroenterology Catheters
• Cardiovascular Catheters
• Neurovascular Microcatheters
• Guiding Catheters
• Balloon Catheters

The use of PTFE liners drastically improves the device trackability. 

2. Introducer Sheaths

The PTFE inner lumen in introducer sheaths provides a low-friction pathway for safe entry of medical devices. Example devices include catheters, guidewires, stents, and balloons. This reduces drag and insertion force, improving procedural control and outcomes.

3. Fluid or Drug Delivery Systems

A fluid delivery system is used to transport a variety of biomaterials, including saline, medications, contrast agents, diagnostic fluids, and more. Common examples of such a system are as follows:

• Infusion Systems
• IV Delivery Sets
• Syringe Pump Systems
• Catheter-based Drug Delivery Devices

Most drug and fluid delivery systems use PTFE liners as the primary fluid pathway. This provides ultra-smooth surfaces and minimal reactivity with sensitive drugs.

4. Diagnostic Tubings

Diagnostic tools require precise and reliable fluid or gas transport. They rely on lubricious inner lumens, often made from PTFE, to ensure low-friction and chemically stable pathways.

Below are a few examples of diagnostic equipment that utilize PTFE tubing:

• Blood Analysis Systems
• Fluid Sampling Systems
• Gas Analysis Devices
• Imaging Equipment
• In-Vitro Diagnostic (IVD) Tool

PTFE liners are the preferred and safest option for transporting biological fluids, sensitive solutions, or reagents.

5. Implants and Sensors

Polytetrafluoroethylene is undoubtedly one of the common materials used in the design of implants and biological sensors. It is biocompatible and remains functional even after prolonged exposure to a dynamic biological environment. There are multiple uses of PTFE when related to implants and sensors, and one of them is as liners or tubing.

PTFE liners are used in endovascular grafts, stent delivery catheters, shunt systems, and drainage pathways. They are critical in procedures such as stent replacement, aneurysm repair, and neurovascular interventions.

On the other hand, the PTFE sleeves act as a protective insulation for sensors and electronics implants. They are used on devices such as pacemaker leads and neurostimulation devices.

6. Heat-Shrink Tubing for Precision Manufacturing

PTFE heat-shrink tubing aids in the manufacturing and assembly of medical devices such as catheters. It ensures proper encapsulation, cladding, and electrical insulation. It also provides temporary protection against contamination, abrasion, and thermal damage.

Broad applications of Hydromer PTFE Heat-Shrink Tubing Include:

• Medical device encapsulation and cladding
• Auxiliary catheter component joining & reinforcement
• Electrode insulation protection

Broad applications of Hydromer PTFE Zebra Heat-Shrink Tubing Include:

• Guidewire integration
• Endoscopy
• Insulation

Hydromer® offers heat-shrink tubing with wall thicknesses as low as 0.01 mm. 

Our PTFE Zebra (spiral-colored) Heat-Shrink Tubing features colored spiral strips for improved visibility and precision during demanding procedures. 

All Hydromer heat-shrink tubing delivers uniform shrinkage, a smooth finish, and wrinkle-free results, even at a 6:1 shrink ratio.

Hydromer® Offers a Complimentary Product Portfolio For Innovative Medical Devices

Hydromer®, Inc. has provided advanced hydrophilic coatings for over 40 years and has recently expanded its product line to include innovative PTFE liners and tubing products.

PTFE Liner Products include: 

1. MatrixLiner® Free Extruded Liner
2. MatrixLiner® Extruded OTW Liner
3. MorphoLiner® Casted OTW Liner

PTFE Tubing Products include:

1. MatrixLiner® PTFE Mini Tubing
2. PTFE Multi-Lumen Tubing
3. PTFE Heat-Shrink Tubing
4. PTFE Zebra Heat-Shrink Tubing

Our PTFE lining and tubing products can be customized to meet specific product, performance, and regulatory requirements.

In addition to our tubing and liners, we also offer a comprehensive range of hydrophilic medical device coatings and coating services. Our contract services include contract R&D, custom coating formulation, contract coating, and analytical testing. 

Lastly, we recently introduced a line of high-performance hydrophilic coating equipment. These include semi- and fully-automated hydrophilic coating systems, friction testing machines, and custom-built equipment. 

Hydromer® has been a trusted partner to leading medical device manufacturers for 40+ years. We are well positioned to help medical device manufacturers develop innovative products and solve complex problems. Our team can provide full-service support to allow you to meet your product development goals.

Advantages of Choosing Hydromer® PTFE Liners and Tubings

We use three advanced processes to manufacture ultra-thin-wall PTFE liners and tubing: FREE Extrusion, Over-The-Wire (OTW) Mandrel Extrusion, and Film Casting. Each process offers unique benefits to medical device manufacturers. 

Below are the top three benefits of selecting Hydromer® PTFE Liners and Tubings:

• Reliable Extrusion Lines: Our production lines enable precise micro-dimensional extrusion, supported by advanced quality inspection to ensure fault-free production.
• Consistent Output: We have scalable production lines and technology to ensure reliable dimensional accuracy across high-volume extrusions.
• Quick Turnaround: Through rapid prototyping and scalable manufacturing capabilities, we support accelerated development timelines.
• Vertical Integration: We offer engineering support, design for manufacturability, regulatory services, material modification, formulation customization, prototyping, testing, validation, and manufacturing services.
• High-Quality Raw Materials: We use premium fluoropolymers to ensure enhanced lubricity, biocompatibility, and long-term device reliability.

Get in Touch

Explore our range of PTFE liners, tubing, hydrophilic coatings, coating equipment, and contract services to see how we can support your product and production needs. Our goal is to help you achieve efficient, high-volume device production and advance medical device development.

Contact us to learn more about our PTFE Liners and Tubing products.