Medical Injection Molding with FDA and USP Class VI Silicones

Silicones are incredibly versatile materials used in a wide range of applications, from baby products to pet care. But for medical devices, it requires a deeper understanding to ensure safety and efficacy. This post will delve into medical injection molding, exploring its applications, and the key considerations for manufacturing medical devices.

What is Medical Injection Molding?

Medical injection molding is a manufacturing process used to produce high-quality components for medical devices. It involves injecting molten material, typically silicone, into a mold cavity under high pressure. This process allows for the mass production of intricate and precise parts with consistent quality and performance.

What is Medical Silicone Molding Used For?

Medical silicone molding is used to manufacture a wide range of medical products, including but not limited to medical tubes and valves, external jacketing on medical cables, surgical tools, patient monitoring systems, and wearables. These components are crucial in various medical applications, such as implants, prosthetics, diagnostic equipment, drug delivery systems, and minimally invasive surgical instruments.

Why Use Silicone for Medical Devices?

Silicone is preferred for medical devices due to its unique properties that make it suitable for a wide range of applications. These properties include biocompatibility, flexibility, durability, resistance to high and low temperatures, chemical inertness, and electrical insulation. Silicone can be formulated to meet specific requirements, making it versatile for various medical applications. Additionally, it’s hypoallergenic, easy to sterilize, and compatible with human tissues, making it an ideal choice for medical implants and devices used in direct contact with the body.

What is the Liquid Injection Molding Process?

Liquid injection molding (LIM) for medical manufacturing requires a mold made of tool-grade steel, hot or cold runner blocks, and related process automation equipment. The tooling and equipment are important, of course, but so is the choice of a medical grade silicone. To promote product safety and ensure regulatory compliance, medical manufacturers can select specialized medical silicones that meet stringent requirements from the U.S. Food and Drug Administration (FDA) and the U.S. Pharmacopeia, a non-profit organization that establishes requirements for medical materials and informs FDA decision making.

FDA and USP Class VI Silicones

The FDA, as a regulatory agency, publishes rules in the Code of Federal Regulations (CFR). CFR 21 177.2600 lists approved elastomers and additives for medical materials, including silicone, which can be cured to meet strict limits for extractables. Depending on the curing method, compounders can provide medical injection molders with elastomers meeting FDA regulations and USP Class VI requirements. 

Among all USP classes, Class VI materials meet the most stringent USP Class VI testing requirements. This includes undergoing stringent testing, including systemic toxicity, intracutaneous, and implantation tests, ensuring safety for medical use. However, not all USP Class VI silicones are equal; some compounders may struggle to guarantee end-product compliance due to supplier changes or inadequate validation processes. Medical manufacturers should seek certificates, like a certificate of conformance (COC) from a third-party testing lab and a certificate of analysis (COA) from the compounder, to ensure material integrity and regulatory compliance.

What is the Difference Between Conventional Silicone & Medical Silicone? 

The primary difference between conventional silicone and medical silicone lies in their intended use and regulatory compliance. Medical silicone undergoes rigorous testing and certification to ensure its suitability for medical applications. It meets strict regulatory standards, such as those set by the U.S. Food and Drug Administration (FDA) and the United States Pharmacopeia (USP), ensuring biocompatibility, safety, and reliability. Conventional silicone may not undergo such stringent testing and may be used in non-medical applications.

Importance of ISO 13485 Certification for Medical Devices & Components

When it comes to choosing a medical manufacturer, find a partner with an ISO 13485 certification. ISO 13485 serves as a global quality standard for companies dealing with medical devices.  Because patient safety relies heavily on the quality of medical equipment, ISO 13485 helps organizations ensure consistent design, development, and manufacturing of these devices, along with their safe and effective operation. That’s why in addition to our ISO 9001:2015 certification, we are actively pursuing our ISO 13485 certification – to demonstrate our unwavering commitment to excellence in the medical device industry.

Medical Injection Molding Companies with USP Class VI Silicones

It can be challenging to find a medical injection molding company, if you don’t know what to look for. At Extreme Molding, we pride ourselves in providing injection molding services that use USP Class VI silicones that are fully validated for FDA, compliant, and have met the USP Class VI testing requirements. We also offer value-added services such as packaging and fulfillment. As a Made in the USA manufacturer, we’ve even helped companies with reshoring production. To learn more about us and how we can help you, contact us.