The cytotoxicity of the copolymers was screened according to the ISO 10993-5 standard for direct contact with cells. The results of the cell viability tests for the L292 mouse fibroblast cell line are presented in Figure . The cytotoxicity threshold, marked as the red dashed line at 70%, was established according to ISO 10993-5. All copolymers displayed cell viability higher than 70%, which indicates that they can be considered non-cytotoxic and have potential for use in biomedical applications. These results were similar to the negative control, medical-grade PCL. Overall, the new segmented PBS-DLS copolymers with varying segmental compositions and modified with PEG showed high cytocompatibility, similar to our previous in vitro and in vivo studies of PBS-DLS modified with hydroxyapatite .