Glioblastomas (GB) are the most common primary brain tumours in adults. Despite current treatments, combining surgical resection with radiotherapy and chemotherapy, the prognosis remains low: less than 16 months. Improving the treatment of GB, in particular by reducing the resistance of these tumours to conventional treatments is therefore a major issue. A major feature of GB is their hypoxic nature. Hypoxia is a mismatch between consumption and oxygen (O2) supply in a tissue. This lack of oxygen promotes tumor growth and resistance to treatments and thus represents a poor prognosis factor.In a direct way, hypoxia is a brake on the effectiveness of radiation therapy. Ionising radiation (RI) used in radiotherapy results in cell death via DNA damage through two distinct mechanisms. IRs can induce breaks on DNA molecule by interacting directly with it or produce free radicals by radiolysis of water molecules. The latter mechanism is predominant but requires the presence of O2. We have demonstrated in the laboratory that IRs and chemotherapy lose efficacy under hypoxic conditions (Près EA et al., Oncotarget, 2015.). Thus, the most hypoxic tumours are also the most resistant to treatment. In order to remove the effects of hypoxia, it was proposed that in tumours, a higher intake of patient-inspired oxygen or an additional intake of oxygenated blood would reduce tumor hypoxia. Thus, it was expected that carbogen inspiration (gas consisting of 95 % O2 and 5 % Carbon Dioxide CO2) by the patient could reduce tumour hypoxia and thus increase the effectiveness of radiotherapy. Very convincing results were observed for different tumour locations, but clinical trial results were negative for GB. We have recently shown in rat in vivo models that carbogen inspiration increases brain blood volume and oxygen saturation of healthy but very limited brain tissue in the most hypoxic and less vascularised tumours (Chakhoyan et al., revision).For several years, studies have examined the use of nanoparticles (NP) as vectors of therapies, especially in cancers because of their ability to accumulate in tumor tissue. This mechanism is due in particular to the EPR (Enhanced Permeability and Retention) effect. Among these nanoparticles, zeolith nanocrystals seem interesting because of their gas retention properties, including CO2 and O2. The Zeoliths we propose to use are prepared in collaboration by the Laboratory Catalyse and Spectrochemistry (CNRS, UNICAEN, ENSICAEN) which ensures its synthesis, characterisation and improvement. They are aluminosilicates of about 10 nm in diameter that have a porous structure conferring great encapsulation and absorption capabilities.However, before any biomedical use, a number of points remain to be validated from a chemical point of view, but also from a biological point of view, especially around the safety of particles.