Cytotoxicity MEM Elution

The aim of the study is to determine the cytotoxic properties of the test item. For this purpose, the potential biological activity of the mammalian cell culture (L929 cell line) in response to the test article extract is used to determine this parameter. Test item is extracted by immersing the device in Minimum Essential Medium (MEM supplemented with 10% Fetal Bovine Serum) for 24 hours or 72 hours (permanent implants or prolonged exposure test articles) at 37 °C. The extracts are then added in wells containing L-929 mouse fibroblast cells. Tissue culture plates and exposed to the test article extract at neat (100%) in 2 replicates. Cells are examined at 48 hours for signs of toxicity after adding the extract. At specific time intervals after exposure trained experts (min. 2) observe the overall health of the cells are visually quantified under a light microscope and a final grade of 0–4 is determined. The achievement of a numerical Grade 3 (moderate reactivity) or greater is considered as cytotoxic effect. The medical device is considered non-cytotoxic if none of the cell cultures exposed to the test item extract shows greater than mild reactivity (Grade 2).