The present invention provides phosphoryl choline derivatives of general formula (I), which are suitable to be immobilized on a solid support to provide a separation material of general formula (II), which bind with both high affinity and high specificity to a protein, more specifically to C-reactive protein and anti-phosphoryl choline antibodies. Said separation materials are particularly useful in the extracorporeal removal of C-reactive protein and anti-phosphoryl choline antibodies from a biological fluid of a patient for prophylaxis and/or treatment of immune dysfunctions and cardiovascular diseases. Also provided is a column that comprises the separation material of general formula (II), as well as a device containing the column. Formula (I), wherein variable X is selected from: —SH, —NHR3, —C═CH, —CH═CH2, —N3 and —CHO; the other variables are as defined in the claims: Formula (II), wherein variable “A” represents a solid support. “A” as well as the other variables are defined in detail in the claims.