Evaluation of Relative Aptamer Binding to Campylobacter jejuni Bacteria Using Affinity Probe Capillary Electrophoresis

Abstract

A qualitative capillary electrophoresis immunoassay was developed for the first-time to evaluate aptamer binding to bacterial cells. Binding affinity of aptamers developed against a Campylobacter jejuni bacterial cell target, relative to other common food-borne pathogens was investigated and specific binding affinity was evidenced by pronounced mobility shift and peak broadening with increasing bacteria concentration for both aptamers. Little to no mobility shift was observed for food-borne pathogens, Salmonella typhirium and Escherichia coli, even when increasing concentrations 10-fold over target. These results suggest that affinity probe capillary electrophoresis could be useful for qualitative screening of aptamer candidates for bacterial cell targets.

Keywords:

• Affinity probes
• aptamer
• bioassay
• Campylobacter jejuni
• capillary electrophoresis
• food pathogen

We wish to thank Dr. Andy Senecal from US Army Soldier & Biological Chemical Command from Natick Soldier Center for providing us with C. jejuni-aptamer sequences (Contract# DAAD16-00-C-09221). We would also like to extend our appreciation to Oak Ridge Associated Universities for the postdoctoral fellowship and Sensors and Electron Devices Directorate of the US Army Research Laboratory in Adelphi, MD for their support.