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, 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 claimed is a device containing a column that comprises separation material made from formula (I) wherein L is a linker as defined in the claims; X is selected from: -SH, -NHR 3 , -C=CH, -CH=CH 2 , -N 3 , -CHO. Also claimed is a separation material of general formula (II): wherein A is a solid support; Y is a group obtainable from the reactive group X.