This study reportsan impact of structure (XRPD, FT-IR)and surfacemorphology (SEM-EDS) of imatinib-functionalized galactose hydrogels,loaded and unloaded with nHAp, on osteosarcoma cell (Saos-2 and U-2OS)viability, levels of free oxygen radicals, and nitric oxide, levelsof BCL-2, p53, and caspase 3 and 9, as well as glycoprotein-P activity.It was investigated how the rough surface of the crystalline hydroxyapatite-modifiedhydrogel affected amorphous imatinib (IM) release. Here, ABCB1 is linked to osteosarcoma.