Chemical Approaches to Prepare Modified Heparin and Heparosan Polymers for Biological Studies

Heparin is a potent clinically used anticoagulant. It is a heterogeneous mixture of polymers that contain a variety of sulfation patterns. Heparin polymers carrying rare 3-O-sulfated glucosamine units have been proven to be critical for binding to antithrombin and elicit an anticoagulant response. Heparins with other sulfation patterns are able to bind to a variety of other proteins such as FGF, VEGF, and CXCL-3. By modulating heparin's sulfation pattern, it is possible to generate polymers that can regulate biological processes beyond hemostasis. In this chapter, we describe a variety of chemical modification methods, including N-acetylation, N-deacetylation, N-sulfation, O-sulfation, selective 2-O desulfation, and complete desulfation, to prepare heparin-like polymers with distinct sulfation patterns for conducting biological studies.