Nanoarchitectonics of penetrating peptide and anionic amphiphiles for dental plaque eradication

Oral biofilm is the primary cause of a wide range of oral diseases, of which dental plaque represents a typical manifestation. To develop effective antibacterial agents for eliminating dental plaque is a huge challenge. Herein, a facile strategy by introducing cell-penetrating peptide octa-arginine (R8) into four anionic amphiphiles, sodium laurate (SL), sodium dodecyl benzene sulphonate (SDBS), bis (2-ethylhexyl) sulfosuccinate sodium (AOT) and sodium deoxycholate (NaCD), is adopted to fabricate nanostructures for antibiofilm application. Cryogenic transmission electron microscopy images clearly show that R8/SL and R8/SDBS form multilamellar vesicles, while R8/AOT and R8/NaCD form nanospheres. The binding of R8 with amphiphiles is revealed by isothermal titration calorimetry. All the structures show bactericidal activity, and the multilamellar vesicles present especially high antibacterial ability. Strikingly, the adhesion and disruption of the vesicles acting on Escherichia coli and Staphylococcus aureus are directly observed. The vesicles quickly disassemble into antibacterial units upon binding to bacteria, and then these units destroy bacterial membranes. In particular, confocal laser scanning microscopy and quantitative evaluation prove that R8/SDBS multilamellar vesicles efficiently inhibit biofilm formation and eradicate mature tooth biofilm, and the validity is also approved by in vivo dental caries experiments. Both in vivo and in vitro experiments have shown that the nanostructures have excellent biocompatibility. This study establishes an effective method by constructing nanostructures with penetrating peptide and anionic amphiphiles to eliminate dental plaque and avoid caries.