Disclosed herein are aptamers that comprise a nucleic acid sequence that has a specific affinity for a target. These aptamers can be used as delivery vehicles to deliver specific agents to particular sites. Alternatively, targeted aptamers can also be used with detection techniques to determine the presence of absence of specific targets in heterogeneous backgrounds.
STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made in part with United States Government support under grant number DE-FG02-93ER61656, awarded by the United States Department of Energy and the U.S. Army Medical Research and Materiel Command (DAMD17-94-J-414) and the United States has certain rights in the invention.