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Top 5 Considerations When Choosing the Right Plastic Resins for Medical Devices

Medical Product

There are several factors to consider when selecting a plastic resin for your medical device requirements. Understanding how medical devices will be used and navigating regulatory requirements is laying the groundwork – it shapes the material choice based on specific functions and ensures the devices we create are safe and effective for patients.

This article will review the most important considerations that every product designer should keep in mind when deciding which plastic resin would work the best for your healthcare devices. By understanding part function you can determine the necessity of biocompatible plastic resins and how they commit to the well-being of those who use your medical devices. Exploring the most common plastic molded medical devices will give us a glimpse into the diverse world of injection molding in the healthcare industry. These questions aren't just steps; they're guiding us toward safe, functional, and compliant medical device design.

Some key considerations when selecting the right plastic resin to use for your medical injection molding devices include;

  1. What is the intended use of Your Medical Device?
  2. What are the Regulatory Requirements for Medical Injection Molded Devices?
  3. What are the Most Common Plastic Resins for the Medical Industry?
  4. Do your Parts Require a Biocompatible Plastic Resin?
  5. What are the Most Common Plastic Molded Medical Devices?

Now, let’s delve into each of these aspects!

What is the intended use of Your Medical Device?

When choosing a plastic material, evaluating the level of contact the device will have with the human body is crucial. For single-use devices with direct or prolonged contact, such as Delivery Systems, choose a plastic resin that is biocompatible to prevent bad reactions. Check if it's safe for long-term use and won't cause allergies. Even for short contact, use materials that follow safety rules for overall patient well-being. Understanding how the device interacts with the body is key when picking the right plastic.

Medical plastic products intended for multi-use have critical considerations such as; biocompatibility, sterilization compatibility, mechanical strength, and chemical resistance. Select materials with established track records in similar medical applications to mitigate risks and enhance patient safety.

What are the Regulatory Requirements for Medical Injection Molded Devices?

Consider whether your medical device requires manufacturing in a clean area. Certain devices, especially those sensitive to contaminants, benefit from white room molding.

A white room is a super clean space used in places like manufacturing facilities. They help keep out tiny particles and keep products clean of contaminants, these rooms are particularly important for making medical devices. A white room ensures that the production environment is controlled and free from particles that could affect the device's quality.

Confirm if your needs require high-quality standards. The top 3 most recommended regulatory requirements are;

  • cGMP
  • ISO certified
  • FDA Registration

Certifications like ISO 9001:2015 indicate that the manufacturer follows stringent quality management systems. This commitment to quality is essential for reliable and consistent production of medical devices. FDA registrations and adherence to Current Good Manufacturing Practices (CGMP) are also crucial. Manufacturers with FDA certification demonstrate that they follow the safety and quality rules set by the government.

IQ (Installation Qualification), OQ (Operational Qualification), and PQ (Performance Qualification) are essential components of the validation process for medical devices. IQ ensures that the device is installed correctly, OQ verifies that it operates as intended under various conditions, and PQ assesses its performance in the actual usage environment. These qualifications are crucial for ensuring the reliability, consistency, and safety of medical devices. Your company may require these validations to help manufacturers meet quality standards, mitigate risks, and ensure that medical devices perform effectively and consistently throughout their lifecycle.

What are the Most Common Plastic Resins Used in the Medical Industry?

Not all plastics are made equal, your product drawing needs to call out a specific material based on desirable characteristics – For example, polyethylene (PE) is a material that has considerable ‘flex’ and is great for medical devices that require bend and transparency. Polycarbonate and ABS are great for medical products that need a durable and strong feel; products like device housings and controllers are commonly associated with robust materials.

Different applications may demand specific mechanical properties such as strength, flexibility, or rigidity. Choose a resin that aligns with the mechanical needs of the device. Common Injection molding materials and characteristics for medical devices include;

Strength:

  • Polycarbonate (PC)
  • Acrylonitrile Butadiene Styrene (ABS)
  • Polyethylene Terephthalate (PET)

Flexibility:

  • Polyvinyl Chloride (PVC)
  • Polyethylene (PE)
  • Thermoplastic Elastomers (TPE)

Rigidity:

  • Polypropylene (PP)
  • Polystyrene (PS)
  • Polyoxymethylene (POM)

Do I Need a Biocompatible Plastic Resin?

Biocompatible materials are designed to interact with biological systems in a way that is safe and effective, without triggering an immune response or causing harm. Think about how long the device touches the body and if it's inside or outside. If the plastic is inside of a body for a long time, like a mouth guard, it needs special materials to avoid adverse reactions or cause any harm to the patient. Additionally, it is important to avoid things like irritation or allergic reactions. Government agencies, like the FDA, have rules that require certain medical devices to be made with materials that won't make people sick.

UL Prospector is a great tool for picking the right plastic resin with biocompatibility in mind. It gives a lot of information about different resins, like technical details, how they perform, and if they follow regulations. When you're working with things like medical devices, biocompatibility is super important. UL Prospector helps you check if the resin you're thinking about using meets the strict standards for how it interacts with living tissues. It tells you about things like cytotoxicity and sensitization, which are crucial factors. This tool is easy to use and helps make a tough job easier by giving you all the details you need to choose the best biocompatible plastic material for your project.

Based on favorable results and resin testing, the FDA will approve materials for medical devices. Some common materials that are often approved by the FDA for medical devices include;

  • Polyethylene (PE): It is widely used for containers, tubing, and orthopedic implants.
  • Polypropylene (PP): Commonly used for containers, closures, and flexible packaging in medical applications.
  • Polyvinyl Chloride (PVC): PVC is used for tubing, blood bags, and medical devices.
  • Polycarbonate (PC): Used in applications such as incubators and medical equipment housings.
  • Polyethylene Terephthalate (PET): Often used for packaging, such as bottles for pharmaceuticals.
  • Polyurethane (PU): Used in catheters, wound dressings, and other flexible medical devices.
  • Polyoxymethylene (POM): Used in components like gears and connectors in medical devices.
  • Polyethylene Glycol (PEG): Used in various medical applications, including drug delivery systems.
  • High-Density Polyethylene (HDPE): Commonly used for laboratory containers, specimen cups, and prosthetic components.

What are the most common Plastic Molded Medical Devices?

Plastic injection molding is a popular method for making important medical devices. Very often, an engineer may be designing a part and not know the best way to manufacture it or what material to use. To make an informed decision when choosing a plastic resin, it is important to know what healthcare products are the best fit for plastic injection molding.

Syringes and needles, crucial for precise medication administration, are typically crafted and designed for injection molding because of the scalability and dimensional compliance of this manufacturing method. Housings for diagnostic equipment, like blood glucose meters and thermometers, are efficiently produced, showing the cost-effectiveness of injection molding. Surgical instruments, such as orthopedic implants, benefit from precise molding of biocompatible plastics for durability and compatibility within the human body. Drug delivery devices, like insulin pens and infusion pumps, use plastic injection molding for intricate and reliable components. Lastly, dental devices, such as impression trays and brackets, highlight the method's importance in ensuring the quality and precision of these critical medical tools. These precision healthcare tools used in various medical procedures allow for the creation of durable, and sterile components essential for successful surgeries.

About Stelray

Stelray Plastic Products’ offers numerous advantages for medical device manufacturers, including high-quality and precise products, cost-effective manufacturing, and design flexibility. With the ability to produce complex and intricate designs with tight tolerances, injection molding is the preferred choice for medical molding solutions.

As technology continues to advance, we can expect to see even more innovations in medical injection molding, making it an essential process in the medical industry.

To learn more about our injection molding services, including our medical molding solutions, get in touch.