The procedure for systematic evolution of ligands by exponential enrichment (SELEX) uses a traditional oligonucleotide library to select high-affinity aptamers for a target of interest.  The library contains numerous fragments, each composed of a randomized central region (40-60 nucleotides) with fixed primer regions (~20 nucleotides) at each end.  In this type of nucleic acid pool, fragments containing a cytosine-rich central region may fold into a four-stranded quadruplex structure called an intercalated motif (i-motif) under slightly acidic, neutral, or even physiological pH conditions.  The author has developed a method for using capillary electrophoresis to separate fragments that can form i-motifs from those in the pool that cannot form i-motifs.  The collected cytosine-rich oligonucleotides thus form an i-motif library, which can be used to screen high-affinity aptamers for an i-motif-bound target.

Creating an i-motif library from randomized nucleic acid pools

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.