Nucleic acid and polypeptide aptamers: a powerful approach to ligand discovery.

Nucleic acid ligands against important targets in infectious, malignant and vascular diseases are continually being discovered by the process of in vitro evolution. Promising methods are being developed for the exploitation of these aptamers in biosensors and other diagnostic devices. Ribosome and mRNA display methods for isolating polypeptide aptamers from highly complex libraries have been developed and have the potential to widen the target range and utility of in vitro evolved ligands.