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Aptamers are oligonucleic acids or peptides that can specifically bind a target molecule.Aptamers are usually selected from a large random oligonucleic acid pool by systematic evolution of ligands by exponential enrichment (SELEX).The key step in SELEX is to isolate target-binding aptamers from the random pool.Widely used isolation methods include affinity chromatography,ultrafiltration,magnetic beads and capillary electrophoresis (CE).All the widely used methods are associated with some apparent drawbacks,such as labor intensive,time consuming,strong non-specific binding towards targets.Therefore,novel methods that can effectively overcome these drawbacks are still much needed.Boronate affinity monolithic capillaries are advanced functional materials appeared in recent years,1,2,3,4 which allow for facile capture/release of cis-diol containing compounds such as glycoproteins in a pH-switchable fashion (high pH on,low pH off).Boronate affinity monoliths have shown great promises in chromatographic separations and biomimetic materials construction.In this study,we developed a boronate affinity monolithic capillary-based SELEX approach for rapid selection of high-specificity glycoprotein-binding DNA aptamers which could solve the problems met by the conventional SELEX methods.As a proof-of-principle work,horseradish peroxidase (HRP),was employed as a target model.HRP was captured by boronate affinity monolithic column under neutral condition,and then the monolithic column was used to select ssDNA that could bind HRP,while the unbound ssDNA was discarded.HRP-ssDNA complexes was evaluated by CE and amplified by PCR.The amplified species were sent for a new round of selection,and the process was repeated again and again until the binding affinity met the requirement or did not decrease any more.After six cycles of selection,aptamers that bind HRP with high specificity and high binding strength were obtained.The approach endowes several advantages over conventional SELEX methods,including faster selection speed,high specificity towards the target molecules and minute reagent consumption.This method is expected to be developed into a universality method to select aptamers of glycoprotein.