A hemocompatible adsorber for separating protein-bound uremic toxins contained in the blood of a patient and having a molecular mass of <;500 g/mol regarding their carrier proteins, to adsorb the uremic toxins during hemodialysis. The hemocompatible adsorber including a polymer based on a cyclic oligosaccharide or a derivative thereof which is disposed on a solid carrier component. A device for hemodiafiltration including an extracorporeal circuit for receiving blood to be purified and a hemodialyzer connected to the blood circulation of a patient, wherein a hemocompatible adsorber is provided for separating protein-bound uremic toxins contained in the blood of a patient and having a molecular mass of <;500 g/mol regarding their carrier proteins. The hemocompatible adsorber, which is disposed on a solid carrier component in at least one layer on the blood side within the hemodialyzer, includes a polymer based on a cyclic oligosaccharide or a derivative thereof.