Kinetic-dependent Killing of Oral Pathogens with Nitric Oxide. (August 2015)

• Record Type: Journal Article
• Authors: Backlund, C.J.; Worley, B.V.; Sergesketter, A.R.; Schoenfisch, M.H.
• Is Part Of: Journal of dental research. Volume 94:Number 8(2015:Aug.)
• Page Start: 1092
• Page End: 1098
• Publication Date: 2015-08
• Subjects: N-diazeniumdiolate -- silica -- dental caries -- periodontal disease -- Aggregatibacter actinomycetemcomitans -- Porphyromonas gingivalis; Dentistry -- Periodicals; Dentistry -- Social aspects -- Periodicals; Dentistry -- Periodicals; Research -- Periodicals; 617.6005
• DOI: 10.1177/0022034515589314
• Languages: English
• ISSNs: 0022-0345

Abstract

Nitric oxide (NO)–releasing silica nanoparticles were synthesized via the co-condensation of tetramethyl orthosilicate with aminosilanes and subsequent conversion of secondary amines to N -diazeniumdiolate NO donors. A series of ~150 nm NO-releasing particles with different NO totals and release kinetics (i.e., half-lives) were achieved by altering both the identity and mol% composition of the aminosilane precursors. Independent of identical 2 h NO-release totals, enhanced antibacterial action was observed against the periodontopathogens Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis with extended NO-release kinetics at pH 7.4. Negligible bactericidal effect was observed against cariogenic Streptococcus mutans at pH 7.4, even when using NO-releasing silica particles with greater NO-release totals. However, antibacterial activity was observed against S. mutans at lower pH (6.4). This result was attributed to more rapid proton-initiated decomposition of the N -diazeniumdiolate NO donors and greater NO-release payloads. The data suggest a differential sensitivity to NO between cariogenic and periodontopathogenic bacteria with implications for the future development of NO-releasing oral care therapeutics.