Are single-use medical devices coated?

Yes, many single-use medical devices are coated — especially when performance, sterilization resistance, or biocompatibility is required. Coatings such as biocompatible chromium (like Armoloy ME-92), PTFE, and Parylene are commonly used depending on the application. ME-92 is typically used on reusable surgical tools, but may also be applied to high-performance single-use components requiring ISO 10993 compliance.

Can welded areas of a component be ME-92 coated?

Yes, ME-92 can be applied to welded areas of components, provided the surface is properly prepared to ensure adhesion. The coating uniformly covers complex geometries and bonded seams, making it suitable for assembled or fabricated medical tools.

What are the benefits of biocompatible coatings for surgical instruments?

Biocompatible coatings like ME-92 enhance surgical instruments by reducing friction, resisting corrosion, improving sterilization compatibility, and minimizing irritation and allergic responses — all contributing to better patient outcomes.

Why would a disposable medical instrument be coated?

Disposable medical instruments may be coated to enhance cutting efficiency, ensure temporary biocompatibility, or prevent corrosion during use. When performance and sterility are critical even for single-use items, coatings like ME-92 provide essential protection.

Intracutaneous Testing | The Armoloy Corporation

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What is Intracutaneous Irritation?

Intracutaneous (or intradermal) irritation testing is used to assess whether a material or its extract causes localized skin irritation when injected just beneath the skin. This test is especially important for evaluating implantable or blood-contacting medical devices, where even trace chemical irritants leaching from a material could cause inflammation, redness, or swelling.

According to ISO 10993-10, any adverse skin reaction such as erythema (redness) or edema (swelling) is monitored over 72 hours. The lower the irritation score, the safer and more biocompatible the material is deemed.

What is an Intracutaneous Irritation Test?

This test involves injecting both test extracts and control substances into rabbits and observing the skin’s reaction at the injection sites. For this study:

ME-92 was extracted using saline (0.9% NaCl) and sesame oil, following ISO 10993-10 extraction guidelines.
Extracts were injected into five sites on the right side of each rabbit.
Corresponding control vehicles (saline or sesame oil) were injected on the left side.
Sites were observed at 24, 48, and 72 hours for signs of erythema and edema.

A difference in mean irritation score of 1.0 or less between test and control groups is considered non-irritant.

ME-92 Intracutaneous Test Summary

ME-92’s coating was applied to 304 stainless steel (Lot #38408) and tested at NAMSA, an ISO-accredited lab. The key findings:

Saline Extract Irritation Score (Test – Control): 0.0
Sesame Oil Extract Irritation Score (Test – Control): 0.0
Erythema/Edema Observed: None beyond slight, isolated redness (Grade 1), consistent with normal injection response
Conclusion: ME-92 coating caused no irritation in this vivo model

All animals remained healthy, and controls behaved as expected, validating the study.

Why Intracutaneous Testing Matters

Biocompatibility is not just about what a coating does—it’s about what it doesn’t do. ME-92 showed no signs of irritation in tissue-contact testing, reinforcing its safety for use in implants, surgical devices, and blood-contact medical tools. Low irritation scores help prevent post-op complications and ensure faster healing.