Rapid One-Step Selection Method for Generating Nucleic Acid Aptamers: Development of a DNA Aptamer against alpha-Bungarotoxin

Background: Nucleic acids based therapeutic approaches have gained significant interest in recent years towards the development of therapeutics against many diseases. Recently, research on aptamers led to the marketing of MacugenH, an inhibitor of vascular endothelial growth factor (VEGF) for the treatment of age related macular degeneration (AMD). Aptamer technology may prove useful as a therapeutic alternative against an array of human maladies. Considering the increased interest in aptamer technology globally that rival antibody mediated therapeutic approaches, a simplified selection, possibly in one-step, technique is required for developing aptamers in limited time period. Principal Findings: Herein, we present a simple one-step selection of DNA aptamers against a-bungarotoxin. A toxin immobilized glass coverslip was subjected to nucleic acid pool binding and extensive washing followed by PCR enrichment of the selected aptamers. One round of selection successfully identified a DNA aptamer sequence with a binding affinity of 7.58 mM. Conclusion: We have demonstrated a one-step method for rapid production of nucleic acid aptamers. Although the reported binding affinity is in the low micromolar range, we believe that this could be further improved by using larger targets, increasing the stringency of selection and also by combining a capillary electrophoresis separation prior to the onestep selection. Furthermore, the method presented here is a user-friendly, cheap and an easy way of deriving an aptamer unlike the time consuming conventional SELEX-based approach. The most important application of this method is that chemically-modified nucleic acid libraries can also be used for aptamer selection as it requires only one enzymatic step. This method could equally be suitable for developing RNA aptamers. Citation: Lauridsen LH, Shamaileh HA, Edwards SL, Taran E, Veedu RN (2012) Rapid One-Step Selection Method for Generating Nucleic Acid Aptamers: Development of a DNA Aptamer against a-Bungarotoxin. PLoS ONE 7(7): e41702. doi:10.1371/journal.pone.0041702 Editor: Maxim Antopolsky, University of Helsinki, Finland Received April 11, 2012; Accepted June 25, 2012; Published July 30, 2012 Copyright: 2012 Lauridsen et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The work was supported by The University of Queensland ECR grant (Project ID 2010002143) awarded to RNV. LHL acknowledges the Novo Nordisk Foundation for supporting his stay at The University of Queensland, Australia. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: rakesh@uq.edu.au