Ionic liquid-incorporated polymeric nanoparticles as carriers for prevention and at an earlier stage of periodontal disease

Periodontal diseases are refractory conditions due to difficulty of removal of biofilm and treating inflammation of periodontal region. We therefore focused on prevention of the periodontal diseases and treating at an earlier stage of the periodontal diseases using drug delivery system by removal of biofilm. In the present study, we developed a drug delivery system comprising ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) incorporated and chitosan-modified polymeric nanoparticles using base materials such as poly (DL-lactide-co-glycolide) (PLGA) and polyvinyl caprolactam – polyvinyl acetate – polyethylene glycol graft copolymer (Soluplus®, Sol). The physicochemical and antibacterial properties, cytotoxicity, morphology of the three types of IL-incorporated polymeric nanoparticles were examined. Additionally, retention ability in the periodontal tissue was determined for the case of treatment in the presence of saliva. Our results indicated that IL-incorporated and chitosan-modified Sol nanoparticles showed the highest antibacterial activity against biofilm bacterial cells, with low cytotoxicity. Electron microscopy imaging revealed that the three types of IL-incorporated and chitosan-modified polymeric nanoparticles had differing antibacterial activities in the micro- and nanoscale. Specifically, retention of polymeric nanoparticles in the periodontal tissue of mice was enhanced following IL incorporation. The use of IL for the preparation of polymeric nanoparticles effectively enhanced their antibacterial activity and retention effect, even in the absence of incorporated drug and can apply for prevention and early treatment of periodontal disease.