Date on Master's Thesis/Doctoral Dissertation


Document Type

Master's Thesis

Degree Name



Oral Biology

Degree Program

Oral Biology, MS

Committee Chair

Demuth, Donald

Committee Co-Chair (if applicable)

Steinbach-Rankins, Jill

Committee Member

Lamont, Richard

Author's Keywords

BAR; porphyromonas gingivalis; streptococcus gordonii; poly-lactic glycolic acid; nanoparticles; sustained-release; double emulsion; biofilm


Periodontal disease is one of the most prevalent infectious diseases worldwide. Between 30-50% of the global adult population suffers from periodontal disease. Some form of periodontitis is present in 46% of American adults, corresponding to annual expenditures in excess of 14 billion dollars for treatment and prevention. Current treatments for periodontal diseases involve mechanical removal of plaque, correction of risk factors, gingival surgery and/or antibiotic therapy. To our knowledge there is no effective therapeutic approach that aims to limit pathogen colonization of the oral biofilm or re-colonization after treatment. Interaction of the pathogen Porphyromonas gingivalis with oral streptococci is critical in the pathogenesis of periodontal diseases. Our previous studies identified a peptide (BAR) that potently inhibited this interaction and reduced P. gingivalis virulence in vivo. However, BAR required higher concentrations and prolonged exposure in limiting P. gingivalis in a pre-established biofilm. This study is aimed at developing targeted BAR encapsulated poly(lactic-co-glycolic acid; PLGA) nanoparticles (NPs) to increase the efficacy of BAR to inhibit P. gingivalis colonization in a dual species biofilm. NPs encapsulating BAR were synthesized using double emulsion solvent evaporation technique. We generated NPs with particle size of 207±19 nm and zeta potential of -15mV. Loading and controlled release properties of NPs were determined using a fluorescently labeled BAR. We showed that BAR-NPs had a total payload of 14.12±0.39 µg/mL of BAR per mg of NP, resulting in the sustained-release of BAR for up to 4 hours. Furthermore, NPs encapsulating BAR peptide potently inhibited pre-formed P.gingivalis/ S. gordonii biofilm. These results suggest that enhanced inhibition of P. gingivalis was be obtained with BAR-NPs, identifying a novel therapeutic approach to effectively targeting P. gingivalis colonization of the oral cavity.