Abstract <p>The technogenic human activity leads to contamination of soils, natural water-bodies and, respectively, food products with different toxic compounds, including radionuclides. Detonation nanodiamonds (DND) are promising materials for purifying aqueous media from micro-amounts of uranium. We have studied the sorption properties of carbon nanomaterials with a different content of DND fractions, when used to absorb the U-238 radionuclide. For the first time, the possibility of purifying aqueous media with low uranium content (1.2 mg/L) has been established. To characterise diamond-containing materials (DCMs) and DND samples, we used the methods of X-ray fluorescence analysis, energy-dispersive X-ray spectroscopy, scanning electron microscopy, FTIR spectroscopy, and low-temperature nitrogen adsorption. The studied DCM and DND samples were different by the sorption capacity to uranium that is determined by their chemical composition and surface properties. We identified the correlations between different characteristics and found out that the uranium adsorption value correlates with the following indices of surface-porous structure of samples as SSA_BET and <i>V</i>_micro. The obtained results demonstrate the possibility of using detonation nanodiamonds as adsorbents of uranium.</p>