ISO 10993-1 Revision Highlights Part 4

Reinforcement of Material and Chemical Characterization

Read previous posts in this series Part 1, Part 2, and part 3.

The importance of material and chemical characterization in biocompatibility evaluation cannot be understated. The last two iterations of ISO 10993-1 strengthened chemical characterization requirements and best practices and placed increasing emphasis on its foundation for device biological evaluation. Chemical characterization is frequently mistaken as being limited to extractables and leachables analyses, yet its scope is more comprehensive. It also involves rigorous examination of material composition, assessment of device manufacturing processes, evaluation of surface properties, and an understanding of potential degradation behaviors.

Clause 6.3 of the sixth edition explicitly designates the gathering of physical and chemical information as the primary step in biological evaluation. The extent of physical and chemical information required depends on the device’s type, intended use, contact duration, and associated biological hazards. Manufacturers are expected to document data not only on the materials of construction but also any processing aids, additives, impurities, plasticizers, pigments, etc. that may influence biocompatibility. Material information is the prerequisite for the identification of biological hazards and for determining whether biological testing is necessary to address specific risks. At times, knowledge of the materials of construction and manufacturing processes could provide the starting point for establishing material equivalence to a clinically established device or safety through scientific justification.

The sixth edition of ISO 10993-1 reinforces a risk-based, stepwise approach to biological evaluation. Where sufficient material information is available and the device’s materials conform to well-established standards (e.g., ISO 5832 series), further chemical analysis may not be required for toxicological or biological assessment. However, processing steps may introduce contaminants or residues, which could potentially leach from the device during use.  Therefore, the evaluation of the finished device in its final form should always be considered. The standard requires that physical, chemical, morphological, and topographical properties of the device and its components be thoroughly assessed. Chemical characterization should be performed in alignment with the principles and requirements outlined in the Annexes of ISO 10993-18.

Manufacturers must maintain robust documentation that details supplier information, chemical identifiers (such as CAS numbers), product codes, detailed material specifications (including properties like purity, molecular weight, and mechanical characteristics), comprehensive formulation details, reference to material standards (e.g., ASTM, pharmacopoeias), and certificates of compliance. These data enable more accurate risk assessments and help ensure that medical devices comply with relevant regulatory and quality standards.

Where qualitative information is insufficient, additional chemical analysis – either qualitative or quantitative – may be necessary to fill gaps and ensure a robust risk assessment. A qualified biocompatibility professional must interpret data and assess biological safety to ensure hazards are correctly identified, regulatory standards are met, and potential risks are minimized. In summary, the 2025 revision strengthens expectations for comprehensive material and chemical characterization to facilitate the identification of relevant biological effects, which may potentially provide manufacturers with opportunities to reduce unnecessary testing.

MED Capabilities

MED Institute provides comprehensive biological risk assessment services to support the safety evaluation of medical devices in accordance with ISO 10993 and related regulatory requirements. Our multidisciplinary team of professionals offers expert guidance on material characterization, biological equivalence assessment, toxicological evaluation of chemical constituents, and even support in responding to submission deficiencies. MED Institute technical experts have extensive experience in developing biological evaluation plans and biological evaluation reports in compliance with global regulatory standards and based on sound scientific principles. By engaging with our team of experts, several manufacturers have designed safer products and accelerated their regulatory submissions and successful market entry.

Contact us today to discuss your project needs 855.463.1633 | askmed@medinstitute.com | medinstitute.com.