Selection of ssDNA Aptamers

Generation of ssDNA is necessary for ensuring that aptamers can fold into unique tertiary structures. In the presence of a complementary strand, a dsDNA helix would form, which hinders selection. The starting material is an ssDNA pool, which is am- 

After the ssDNA pool has been established, it must be de- and renatured as described for RNA aptamers (see Section 7.3.1.5). Then preselection and selection are done, and the selected ssDNA is used in a PCR to create the new dsDNA pool of the next selection round. 

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