Heparin spacer groups

This chapter focuses on the effects of anticoagulant activity caused by specific functional group derivatization of heparin, and on preliminary immobilization spacer group evaluations. The functional groups selected for immobilization are hydroxyl and carboxylic heparin groups. 

Fig. 33.1. Structure of DNA aptamers for recognition fibrinogen (A) [15,29] and heparin binding sites (B) [17] of thrombin. The non-canonical hydrogen bonds between guanines are shown by dotted lines. In the case of structure (A), the spacer composed of 15 T chain terminated by thiol group at the end of hydrophobic spacer is shown [34]. (C) Structure of RNA aptamer against fibrinogen binding site of thrombin [23].

Figure 9. APTT vs. spacer unit carbon number results for heparin immobilized via carboxylic groups to diaminoalkane agarose gels. Key —, the baseline APTT (i.e.y unheparinized plasma) , respective control substrate APTT (i.e., untreated diaminoalkane agarose gels) and O, respective heparin immobilized gels.

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