biocompatibility

Biocompatibility is the ability of a material to perform with an appropriate host response in a specific biomedical application. In medical devices, implants, and tissue engineering constructs, biocompatibility means that the material does not provoke an adverse reaction that impairs function or harms the patient. Compatibility is not a property of the material alone; it emerges from the interaction of the material with biological systems over the duration of contact, and depends on tissue type, route of exposure, and implantation site.

Key aspects of the host response include protein adsorption, cellular adhesion, and inflammatory processes at the tissue interface, followed by foreign body reactions or tissue integration. Biocompatibility aims to minimize cytotoxicity, hypersensitivity, systemic toxicity, and thrombosis or hemocompatibility problems, while enabling the intended mechanical or functional integration. Degradation products and leachables from the material can also influence compatibility and are routinely evaluated.

Biocompatibility is assessed through a risk-based program aligned with standards such as the ISO 10993 series and relevant regulatory guidance. In vitro tests assess cytotoxicity, sensitization, and irritation; in vivo studies address implantation effects and systemic toxicity; additional assessments cover genotoxicity and hemocompatibility. Results are contextualized for the device class, duration of contact, and patient population. Materials and processing steps, including sterilization, surface modification, and residue control, are optimized to achieve the desired biocompatibility.