USP Class VI Silicone
USP Class VI silicone materials are biocompatible elastomers that have low levels of extractables, substances that can migrate at elevated temperatures or with surface exposure. These elastomers are safe for contact with human skin or living tissue and can be implanted for less than 29 days with adverse health effects. USP Class VI silicones are hypoallergenic and resist chemicals, fluids, and biological growth. They are platinum-cured for cleanliness and purity.
ElastaPro is a Made in USA manufacturer of USP Class VI silicones. We offer these specification grade materials as solid silicone sheets, continuous rolls, and uncured compounds. Our medical grade silicones also meet FDA Title 21 CFR 177.2600, ISO 10993, and European Pharmacopoeia requirements. Visit the links below for more information.
What is USP Class VI?
USP Class VI is a stringent biocompatibility standard from the United State Pharmacopeia (USP), a non-profit organization. The U.S. Food and Drug Administration (FDA) recognizes and uses this standard, which establishes testing protocols and complements the FDA’s own CFR 177.2600. USP Class VI silicones are typically used in seals, gaskets, and medical tubing. They’re also used in short-term (less than 29 days) implants.
USP Class VI compliance ensures that a material is safe for biological use. More specifically, USP Class VI silicones must pass these tests.
- Systemic toxicity (whether it causes harmful effects in the body)
- Intracutaneous reactivity (whether it causes irritation to tissues)
- Implantation tests (how the material behaves when implanted in living tissue)
These tests are typically done on animal models, usually rabbits or mice, and ensure the material won’t cause adverse biological reactions.
USP Class VI Solid Silicone Sheet and Continuous Rolls
ElastaPro calendars USP Class VI silicones into solid elastomers that can be die cut into parts for peristaltic pumps, insulin pumps, and other types of medical devices and equipment. This process creates flexible, durable silicone sheets that can be precisely controlled for thickness, texture, and other properties.
USP Class VI solid silicone sheet is available in:
- Durometers: 10 to 70 Shore A
- Thicknesses: .007” to .500”
- Widths: Up to 60”
- Colors: While typically translucent, various colors are availabe
These products are Made to Order and supplied in a gloss or matte finish. ElastaPro can also supply you with silicone rolls that we can slit-to-width for automated cutting operations.
USP Class VI Uncured Silicone Compound
In addition to medical grade silicone sheets, ElastaPro offers uncured silicone compound that arrives ready-to-mold. Our materials are supplied rolled-up off the mill or in sheet form with a poly liner.
What are USP Classes?
The U.S. Pharmacopeia (USP) is a non-profit organization that defines requirements for medicines, pharmaceuticals, and healthcare products such as medical materials. USP standards aren’t regulations, but they inform decision-making at agencies like the U.S. Food and Drug Administration (FDA). For example, the Federal Food, Drug and Cosmetic Act (FDCA) recognizes USP quality standards for medicines.
As a government agency, FDA publishes its rules in the Code of Federal Regulations (CFR). For example, FDA CFR 21 177.2600 lists the elastomers, accelerators, retarders, activators, antioxidants, plasticizers, fillers, emulsifiers, and other additives that can be used in food and medical applications. This list includes silicone rubber, a synthetic elastomer, that can be platinum-cured to meet low limits for extractables.
Restriction of Hazardous Substances (RoHS), a European Union (EU) Directive, also restricts the use of certain substances. RoHS is associated with recyclable products and the electrical and electronics industries, but medical manufacturers also need to know whether silicone components such as keypads, buttons, and gaskets are made of compliant materials.
For its part, USP publishes test instructions and standards for the plastics, polymers, and elastomers that are used in medical devices and surgical equipment. Because these materials may come into contact with human tissue, these USP tests measure biocompatibility. The tests also correspond to numbered classes so that the healthcare industry can identify materials in a standard way.
Among USP classes, Class VI materials meet the most stringent testing requirements. USP Plastic Class VI, as this group is also known, includes silicones that pass a systemic toxicity test, an intracutaneous test, and an implantation test. These tests are directly related to the intended end-use of the silicone article and account for conditions such as patient contact time and temperature.
Frequently Asked Questions about USP Class VI Silicones
Here are some frequently asked questions (FAQs) with answers about these medical grade elastomers.
Q: Is USP VI the same as USP Class VI and USP Class 6?
Yes, USP VI is the same as USP Class VI and USP Class 6.
Q: What are USP Class VI requirements?
USP Class VI requirements involve a series of biological reactivity tests to demonstrate biocompatibility. Specifically, these requirements include passing acute systemic toxicity, intracutaneous, and implantation tests using live animals to evaluate the material’s biological effects. Materials must also meet specific requirements for temperature exposure during testing.
Q: What are the biological reactivity tests in USP Class VI requirements?
There are three biological reactivity tests.
- Acute Systemic Toxicity: Extracts of the material are injected into test animals (usually mice) to evaluate any acute systemic toxic or irritant reactions over a 72-hour period.
- Intracutaneous: Extracts are injected under the skin of test animals (usually rabbits) to assess local irritation and toxicity.
- Implantation: Samples of the material are surgically implanted into the muscle tissue of test animals (usually rabbits) and observed for a set period, typically five to seven days, to check for negative tissue responses like irritation or infection.
Q: Are there any other USP Class VI requirements?
Yes. There are four.
- Extraction fluids: The materials are extracted using a variety of fluids, including saline, vegetable oil, alcohol saline, and polyethylene glycol, to simulate different potential exposure scenarios.
- Temperature exposure: Extracts are exposed to different temperatures for specific durations before the toxicity tests are performed.
- Material composition: Materials must not only pass the physical and biological tests but also be free of certain animal-derived ingredients for certain medical applications.
- Consistency: The material must be consistent in its purity, strength, quality, and composition to ensure reliable performance
Q: What are USP Class VI sealing products?
USP Class VI sealing products for sealing are high-purity biocompatible materials that undergo rigorous testing to meet the biological reactivity standards set by the U.S. Pharmacopeia (USP). These elastomers are used in seals, gaskets, and O-rings for medical devices and biopharmaceutical equipment where contact with human tissues and fluids is possible, ensuring safety and preventing contamination in high-purity applications. Silicones are typically used, but USP Class VI sealing products are also made from EPDM or PTFE (Teflon).
Q: What are the major types?
There are seven major types of USP Class VI sealing products.
- O-rings
- Gaskets
- Diaphragms
- Sealing Profiles and Extrusions
- Sanitary Seals and Tri-Clamp Gaskets
- Custom Molded Sheets
- Valve Seats and Sealing Components
Note: ElastaPro is a materials manufacturer and not a fabricator. In other words, we make the materials but not the components.
Ask ElastaPro for USP Class VI Silicones
Do you need USP Class VI silicones for medical devices or equipment? Contact ElastaPro for specifications grade solid silicone sheets, continuous rolls, and ready-to-mold compounds. Our medical grade elastomers meet USP Class VI requirements and they also comply with FDA Title 21 CFR 177.2600 regulations and ISO 10993 and European Union Pharmacopeia standards.
