Building a Top-Rate Biocompatibility Testing Process for Medical Devices

Biocompatibility testing of medical devices is a complex, but essential requirement for bringing safe products to market. In this blog, we will talk about biocompatibility testing, why it matters, the ISO guidelines, and how to make the process more efficient.

^{This article is posted on our Science Snippets Blog}  

What is biocompatibility testing?

Medical devices, like pacemakers, insulin pumps, and surgical tools, are used every day in a variety of medical applications. But first, manufacturers need to make sure they are safe for patients.

Biocompatibility testing is a crucial aspect of this safety assurance. Biocompatibility, in the context of medical devices, refers to the ability of a device or material to interact safely with the human body. This rigorous assessment process is vital to prevent adverse reactions, enhance product efficacy, and comply with regulatory standards.

Why is biocompatibility testing important?

Bodily fluids can react with the materials used in medical devices. For example, when blood comes into contact with the surface of a device, it can trigger dangerous clotting due to material incompatibility. Similarly, metal components in contact with bodily fluids can corrode and release ions, causing adverse reactions or even tissue damage over time.

Biocompatibility testing is a critical checkpoint for catching potential risks early in the development and manufacturing of medical devices, so the final products are safe and effective.

ISO guidelines for biocompatibility testing

Biological evaluation falls within the strict regulatory framework that governs the medical industry. These guidelines outline the necessary testing protocols, which vary based on the nature of the product, its intended use, and the duration of contact with the human body.

ISO 10933 from the International Organization for Standardization (ISO) is the cornerstone for biocompatibility testing of medical devices, and a primary reference point for major global regulatory bodies in Europe, Asia, and the United States. The ISO 10993 series provides a detailed framework for evaluating the biological safety of medical devices and covers a wide range of potential interactions with the human body.

Types of biocompatibility testing

Biocompatibility testing needs to answer a range of questions about the material components used in the finished medical device. If it’s not possible to test the entire final product, then a representative sample of the medical device is prepared according to ISO 10993 recommendations. The choice of tests depends on the medical device and its intended use:

• Cytotoxicity: Does it affect cell health, growth, and proliferation?
• Sensitization: Does it trigger an allergic reaction?
• Irritation: Does it irritate or damage the skin or subcutaneous tissue?
• Long-term effects: Does prolonged exposure affect surrounding tissues and organs?
• Hemocompatibility: Does it cause blood clotting or other adverse reactions?

General biocompatibility testing workflow

The biocompatibility testing process typically begins with material characterization, where the physical and chemical properties of the materials used in the medical device are documented and analyzed. Depending on the intended use of the product, the contact duration, and the assessed risks, the next set of tests may include cytotoxicity, sensitization, irritation, systemic toxicity, or others.

Samples are then prepared, often in the form of extracts to simulate the conditions in living tissues. These samples are tested using standardized protocols, in either controlled laboratory settings (in vitro) or, for certain assessments, using animal models (in vivo).

Risk-based approach to testing

Regulatory bodies, like the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA), require that manufacturers of medical devices perform risk assessment as part of their regulatory submissions. This analysis is done early in development to identify potential hazards associated with the medical device's materials and its interaction with the human body. Having this data sooner, helps to guide decisions about design, materials, and testing protocols.

A thorough analysis also streamlines workflows and reduces the costs of biocompatibility testing. If a material has a well-documented history of safe use, some tests may not be necessary. This allows manufacturers to prioritize and ensure that biocompatibility testing is focused on the most relevant and potentially risky aspects of the device.

The role of lab essentials

The choice of lab essentials directly impacts the accuracy, reliability, and repeatability of test results. To ensure product quality and safety, it’s best to choose well-known brands, establish rigorous maintenance and calibration procedures, and train personnel in proper instrument use.

Current analytical methods in biocompatibility testing rely heavily on mass spectrometry to measure ultra-traces of extractables and leachables (E&L). For the best results, it’s critical to use ultra-pure water and reliable plastic consumables when preparing eluents and calibration standards.

Connectivity and compliance support are also essential; regulated labs need a full record of protocols and results for traceability and audit-readiness. Connected tools also have the benefit of automated reminders about regular maintenance and feature upgrades, ensuring the best performance.  

Solutions for biocompatibility testing

Sartorius’ lab essential instruments are well recognized for offering the performance, usability, and connectivity that medical device manufacturers need. Cubis^® II analytical balances and Picus^® 2 electronic pipettes easily integrate with existing workflows, in addition to offering dedicated apps for managing workflows, devices, operators, and routine maintenance.

For HPLC and other elemental analyses, a reliable source of high-quality water, like Arium^® Ultrapure Water Systems, can prevent up to 80% of data artifacts. Minisart^® Syringe Filters with industry-leading Sartorius membranes also provide robust particle removal from samples and help prevent clogging in chromatographic analysis.

Learn more about Sartorius’ solutions for medical device testing and QC.