When this test applies
ISO 10993-1:2025 flags hemocompatibility for every device that contacts circulating blood, directly or indirectly. ISO 10993-4:2017 breaks the endpoint into categories — thrombosis, coagulation, platelets, haematology and immunology (complement) — and selects tests by device category and contact duration. The direct-contact method is appropriate where the blood-contacting surface is what matters — coatings, metals, textured surfaces — and where a static model is adequate for the device category.
When to run it
After cytotoxicity, and once the material, surface finish and any coating are settled, because blood interaction is sensitive to surface condition and processing residues. Run it in one campaign with the other blood-interaction tests your device category calls for, on finished, sterilised samples.
What a pass tells you
That blood-contact parameters measured after the contact period showed no significant difference from the concurrent negative control, with the positive control performing as expected — a pass under ISO 10993-4 for the parameters assessed.
What it does not tell you
A static direct-contact result is not a model of flow; thrombogenicity under circulation is assessed by the blood loop assay. It also covers only the parameters measured in the study design — hemolysis by extract, complement activation and coagulation are separate determinations — and nothing outside hemocompatibility.
Method
Testing per ISO 10993-4:2017. The device or a representative sample of its blood-contacting surface is placed in direct contact with fresh, anticoagulated blood for the defined contact period, alongside negative and positive reference materials. The blood is then assessed for the compatibility markers specified in the study design. Where a sample rather than the whole device is used it must represent the finished, sterilised blood-contacting surface. Extraction ratio follows ISO 10993-12: 6 cm²/mL for material under 0.5 mm thick, 3 cm²/mL at 0.5 mm or thicker, or 0.1 to 0.2 g/mL where surface area is indeterminate.
Where it runs
This method is internationally sourced (OUS). The laboratory is ISO/IEC 17025 accredited and GLP certified, and the report is issued under Groenakker’s ISO 13485:2016 certified quality system, in Groenakker’s report template or in your document template on request at no extra cost.
Usually ordered alongside
The other hemocompatibility parameters your device category calls for — hemolysis, complement activation, platelet and leukocyte counts and PTT — plus cytotoxicity as the baseline screen. A biological evaluation plan is the cheapest way to establish which blood-interaction tests are actually required for your device rather than commissioning all of them.
