DNA-APTAMER-NANOGRAPHENE OXIDE AS ATARGETED BIO-THERAGNOSTIC SYSTEM IN ANTIMICROBIALPHOTODYNAMIC THERAPY AGAINST PORPHYROMONASGINGIVALIS

Background and Aim : The aim of this study was to design and evaluate the specificity of atargeted bio-theragnostic system based on DNA-aptamer-nanographene oxide (NGO) againstPorphyromonas gingivalis during antimicrobial photodynamic therapy (aPDT).Methods : Following synthesis and confirmation of NGO, the binding of selected labeledDNA-aptamer to NGO was performed and its hemolytic activity, cytotoxic effect, and releasetimes were evaluated. The specificity of DNA-aptamer-NGO to P. gingivalis was determined. Theantimicrobial effect, anti-biofilm potency, and anti-metabolic activity of aPDT were then assessedafter the determination of the bacteriostatic and bactericidal concentrations of DNA-aptamer-NGOagainst P. gingivalis. Eventually, the apoptotic effect and anti-virulence capacity of aPDT basedon DNA-aptamer-NGO were investigated.Results : The results showed that NGO with a laky, scale?like, and layered structure innon?cytotoxic DNA?aptamer?NGO has a continuous release in the weak?acid environment withina period of ۲۴۰ h. The binding specificity of DNA?aptamer?NGO to P. gingivalis was confirmedby flow cytometry. When irradiated, non?hemolytic DNA?aptamer?NGO were photoactivated,generated ROS, and led to a significant decrease in the cell viability of P. gingivalis (P < ۰.۰۵).Also, the data indicated that DNA?aptamer?NGO?mediated aPDT led to a remarkable reductionof biofilms and metabolic activity of P. gingivalis compared to the control group (P < ۰.۰۵). Inaddition, the number of apoptotic cells increased slightly (P > ۰.۰۵), and the expression level ofgenes involved in bacterial biofilm formation and response to oxidative stress changedsignificantly after exposure to aPDT.Conclusion : It is concluded that aPDT using DNA-aptamer-NGO as a targeted bio-theragnosticsystem is a promising approach to detect and eliminate P. gingivalis as one of the main bacteriainvolved in periodontitis in periopathogenic complex in real-time and in situ.

کلیدواژه ها:

Aptamer ، Porphyromonas gingivalis ، Antimicrobial photodynamic therapy ، Nanographene oxide