In vitro selection of aptamers: the dearth of pure reason.

In vitro selection experiments are now routinely used to identify functional nucleic acid residues and structures, and have become a tool for studying molecular recognition, molecular biology, and molecular evolution. Technical innovations that have been made during the past year include the use of modified monomers to increase stability and photocross-linking reagents to improve affinity. These advances should dramatically increase the utility of aptamers in the future.