What is an Aptamer?
Aptamers are synthetic nucleic acid-based affinity ligands that are isolated based on their ability to bind specifically and with high affinity to a given target. These short nucleic acid sequences (DNA or RNA) have a flexible backbone capable of folding into highly organised, complex structures. These structures, characterised by stem-loops, hairpins and other secondary structures, forming complementary shapes that wrap around all or part of their target (in the case of small molecules) or fit snugly into clefts and gaps within the surface of much larger target molecules (for proteins, cells, tissues etc). This ability to fold into or around the complex surfaces of a target, means that it is possible to select aptamers against almost any given target, with exquisite specificity.