Abstract: Microparticles containing heparin or a heparin-like polymer and a biocompatible polymer are described. The heparin or the heparin-like polymer and the biocompatible polymer can be indirectly linked together by a coupling agent, which can have a structure represented by Formula I, (A)p(R)(D)q, wherein A is a bond or a moiety that can form a bond with the heparin or the heparin-like polymer, D is a bond or a moiety that can form a bond with the biocompatible polymer, R is a linker for A and D, and p and q are from 1 to 25. Methods of making the microparticles include mixing a first solution of the heparin or the heparin-like polymer and a second solution of the biocompatible polymer, to form a mixture, and adding the mixture to an oil and a surfactant and homogenizing the mixture to form a water-in-oil emulsion. Compositions of these microparticles are also described.