DNA electrochemical biosensor for the detection of ۱۶s rRNAgene sequence related to the Enterococcus faecalis

Background and Aim : Some of microorganisms are potential pathogens that can be infectiousagents under some circumstances. From enterococcal species, Enterococcus faecalis (E.faecalis)and Enterococcus faecium commonly colonize and infect human in detectable numbers. They area cause of bacteremia, bacterial meningitis, urinary tract infections, endocarditis, woundinfections, and various other infections in human. Enterococcal infections now roughly accountfor ۱۲% of nosocomial infections in US with a major cause by E. faecalis (> ۸۰%) andEnterococcus faecium being major reason of the remaining Infections.Methods : In the present study, an Enterococcus faecalis (E. faecalis) DNA biosensor (efbiosensor)was fabricated to quantify the bacterium genome. A specific E. faecalis DNA probewas selected from ۱۶S rRNA sequence of E. faecalis and immobilized on a gold electrode surfacein an optimized time to fabricate the ef-biosensor.Results : The ef-biosensor detected a synthetic target of the probe with a detection limit of ۳.۳amol L-۱ and with a nice selectivity to resolve from one-, two- and three-base mismatchedsequences. In addition, the bacterium genomic DNA was quantified with a detection limit of۷.۱×۱۰-۹ ng mL-۱ in a concentration range of ۱.۱×۱۰-۷ to ۱.۱ ng mL-۱. The ef-biosensor had along-time stability, good fabrication reproducibility and good regeneration ability.Conclusion : The ef-biosensor was successfully applied for E. faecalis detection in humansamples.

کلیدواژه ها:

E. faecalis ، Pathogen ، Genosensor ، Electrochemical biosensora