Bioinspired molecular engineering of bivalent aptamers by ligand-induced self-dimerization.

A bioinspired "point-and-shoot" molecular strategy is described for engineering noncovalent aptamers via K + -induced reassembly of a split G-quadruplex sequence at the end of monomeric aptamers. This design compensates for insufficient cell recognition of monovalent aptamers in biological environments and minimizes structure-induced nonspecific cell binding, expending the aptamer toolbox available for complex systems.