title: One-pot synthesis of antibacterial monomers with dual biocidal modes.
abstract: OBJECTIVE
  The present study reported a method for preparing a blend of antibacterial quaternary ammonium silanes and quaternary ammonium methacryloxy silane (QAMS) based on the sol-gel reaction between dimethyldiethoxy silane and two trialkoxysilanes, one with an antibacterial quaternary ammonium functionality and the other with a methacryloxy functionality.
  
  
  METHODS
  Reaction products of the sol-gel reaction were characterised by direct infusion mass spectrometry, FTIR and proton, carbon and silicon NMR. This blend of monomers was incorporated into an experimental universal adhesive for evaluation of antimicrobial activity against Streptococcus mutans biofilms, microtensile bond strength and cytotoxicty. Retention of quaternary ammonium species on polymerised adhesive, leaching of these species from the adhesive and the ability of resin-dentine interfaces to inhibit S. mutans biofilms were evaluated over a 3-month water-ageing period.
  
  
  RESULTS
  The antibacterial adhesive version killed bacteria in S. mutans biofilms not only through the release of non-copolymerisable quaternary ammonium silane species (release-killing), but also via immobilised quaternary ammonium methacryloxy silane that are copolymerised with adhesive resin comonomers (contact-killing). Contact-killing was retained after water-ageing. The QAMS-containing universal adhesive has similar tensile bond strength as the control and two commercially available universal adhesives, when it was used for bonding to dentine in the etch-and-rinse mode and self-etching mode. Incorporation of the antimicrobial quaternary ammonium species blend did not adversely affect the cytotoxicity of the universal adhesive formulation.
  
  
  CONCLUSIONS
  Instead of using quaternary ammonium dimethacrylates and nanosilver, an alternative bimodal antimicrobial strategy for formulating antimicrobial universal dentine adhesives is achieved using the one-pot sol-gel synthesis scheme.
  
  
  CONCLUSIONS
  The QAMS containing universal dentine adhesives with dual antimicrobial activity is a promising material aimed at preventing second caries and prolonging the longevity of resin composite restorations.
authors.affiliation: Department of Stomatology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Stomatology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Xiao-Juan
authors.initials: XJ
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, China.
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Niu
authors.affiliation: Hospital of Stomatology, Wuhan University, Wuhan, China.
authors.forename: Si-Ying
authors.initials: SY
authors.lastname: Liu
authors.affiliation: Department of Stomatology, North Sichuan Medical College, Nanchong, China.
authors.forename: Wan-Chun
authors.initials: WC
authors.lastname: Zhu
authors.affiliation: Prince Philip Dental Hospital, The University of Hong Kong, Hong Kong Special Administrative Region.
authors.forename: Jeevanie
authors.initials: J
authors.lastname: Epasinghe
authors.affiliation: Research and Development, Bisco Inc., Schaumburg, IL, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Stomatology, Fuzhou Dongfang Hospital, Fuzhou, China.
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Li
authors.affiliation: Hospital of Stomatology, Wuhan University, Wuhan, China.
authors.forename: Cui
authors.initials: C
authors.lastname: Huang
authors.affiliation: Department of Stomatology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China. Electronic address: maojing@hust.edu.cn.
authors.forename: Jing
authors.initials: J
authors.lastname: Mao
authors.affiliation: College of Dental Medicine, Georgia Reagents University, Augusta, GA, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
authors.affiliation: College of Dental Medicine, Georgia Reagents University, Augusta, GA, USA. Electronic address: ftay@gru.edu.
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D058491:Bacterial Load / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003804:Dentin / Q000382:microbiology / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D004058:Diffusion; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008422:Materials Testing; D008689:Methacrylates / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D050296:Microbial Viability / Q000187:drug effects; D009804:Odontoblasts / Q000187:drug effects; D017646:Organosilicon Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D044367:Phase Transition; D000644:Quaternary Ammonium Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D051381:Rats; D012821:Silanes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D017550:Spectroscopy, Fourier Transform Infrared; D013295:Streptococcus mutans / Q000187:drug effects; D013314:Stress, Mechanical; D013718:Tensile Strength; D013997:Time Factors
chemical_list: C542237:3-methacryloxypropyltrimethoxysilane; D000900:Anti-Bacterial Agents; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D017646:Organosilicon Compounds; D000644:Quaternary Ammonium Compounds; D012821:Silanes; C018408:3-(trimethoxysilyl)propyldimethyloctadecylammonium
keywords: Antibacterial; Biofilm; Dual biocidal modes; Interface; Universal adhesive