text: There is great potential for RNA interference (RNAi) to be used therapeutically to reversibly silence any gene. For RNAi to realize its therapeutic potential, small interfering RNA (siRNA) must be delivered to the site of action in the cells of target tissues. But finding safe and efficient delivery mechanisms is a major obstacle to achieving the full potential of siRNA-based therapies.  Unmodified siRNA is unstable in the bloodstream, has the potential to cause immunogenicity, and has difficulty readily navigating cell membranes. As a result, chemical alterations and/or delivery tools are needed to safely transfer siRNA to its site of action.
  There are three main techniques of delivery for siRNA that differ on efficiency and toxicity.