Capillary electrophoresis‐based methodology for screening of oligonucleotide aptamers

As a new molecular recognition element, oligonucleotide aptamer not only has higher affinity and specificity to target molecules, but also has the advantages of wide recognition range, in vitro synthesis and chemical stability compared with conventional antibodies. Since a kind of screening method termed systematic evolution of ligands by exponential enrichment (SELEX) was reported, scientists have extensively researched the methodology of how to highly and efficiently screen out aptamers from a library consisting of a large number of random oligonucleotides. Certainly capillary electrophoresis-based screening methodologies, including nonequilibrium capillary electrophoresis of equilibrium mixtures, equilibrium capillary electrophoresis of equilibrium mixtures, non-SELEX, ideal-filter capillary electrophoresis, capillary transient isotachophoresis, etc., are revolutionary. Compared with conventional SELEX, these capillary electrophoresis-based methodologies show incomparable advantages such as the single-round screening of aptamers and increased successful screening rate. Methodology studies on the screening process of aptamers are comprehensively reviewed.