The project aims to develop novel biomaterials based on hydroxyapatite and mesoporous silica, loaded with newly designed chemotherapeutic agents specifically tailored for bone cancer and metastases, to be administered in situ following resection of the bone tumour or metastasis and implantation via injection of a bone substitute biomaterial. The objective is to overcome the limitations and side effects of conventional systemic administration of chemotherapeutic agents used in the treatment of bone cancer, including metastatic forms. Therefore, nanostructures loaded with chemotherapeutic agents, based on cisplatin, will be designed, prepared, and characterized at each preparatory step, from a structural, morphological, dimensional, compositional, drug loading, and release capacity perspective. Additionally, biodegradation experiments and studies on cell cultures will be conducted to evaluate the therapeutic efficacy of the new nano-biomaterials.