| abstract |
A carrier for in vivo delivery of a therapeutic agent comprising a thiol group is provided, wherein the therapeutic agent is conjugated to the carrier via a biodegradable disulfide bond. Since extracellular fluids in vivo do not provide the appropriate environment to efficiently reduce a disulfide bond, while cellular cytosol does provide an appropriate environment, the agent will remain substantially coupled to the carrier while circulating through the body until the carrier crosses a cell membrane. As a result, the therapeutic agent is protected from degradation and renal clearance, and the potential for the therapeutic agent to elicit an immune response is limited. |