Evaluation of Biocompatibility Using In Vitro Methods: Interpretation and Limitations - Tissue Engineering: Cell-Surface Interactions for Tissue Culture - page 142

Fig. 6 Schematic overview of the sequence of ten important questions (Q1-10) which arise
when assessing for in vitro biocompatibility
resulting in subconfluent cultures after 6 days. Furthermore, three culture
medium extracts are prepared instead of one: one according to ISO 10993-5
(24-h extract at 37 C). For the second extract, the sample used to obtain the first
24-h extract is transferred to the same quantity of fresh medium and incubated
for another 24 h at 37 C (24-48-h extract). A 48-72 h extract is prepared
similarly. With these extracts of the sample, compounds are extracted that are
not released during the first 24 h or 48 h of incubation. Cells are allowed to
adsorb and adhere for 24 h before addition of the extract media at different
concentrations. As diluent, a medium is used that was treated similarly but
without the test sample. Total culture cell mass (measured by parameters such as
total culture cell protein or DNA) is assessed five days after addition of the