Document Type


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School of Pharmacy


Pharmaceutical Sciences


Toxin B is one of the major virulence factors of Clostridium difficile, a bacterium that is responsible for a significant number of diarrhea cases in acute care settings. Due to the prevalence of C. difficile induced diarrhea, rapid and correct diagnosis is crucial in the disease management. In this study, we have employed a stringent in vitro selection method to identify single-stranded DNA molecular recognition elements (MRE) specific for toxin B. At the end of the 12-round selection, one MRE with high affinity  nM) for toxin B was identified. The selected MRE demonstrated low cross binding activities on negative targets: bovine serum albumin, Staphylococcus aureus alpha toxin, Pseudomonas aeruginosaexotoxin A, and cholera toxin of Vibrio cholera. A modified sandwich ELISA assay was developed utilizing the selected ssDNA MRE as the antigen capturing element and achieved a sensitive detection of 50 nM of toxin B in human fecal preparations.

Source Citation

Hong, K. L., Maher, E., Williams, R. M., & Sooter, L. J. (2015). In VitroSelection of a Single-Stranded DNA Molecular Recognition Element againstClostridium difficileToxin B and Sensitive Detection in Human Fecal Matter. Journal of Nucleic Acids, 2015, 1–12.


Copyright © 2015 Ka Lok Hong et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.



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