van der Mei H C, Engels E, de Vries J, Busscher H J
Department of Biomedical Engineering, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands.
Caries Res. 2008;42(1):19-27. doi: 10.1159/000111746. Epub 2007 Nov 27.
The amine fluoride (AmF) N'-octadecyl-trimethylene-diamine-N,N,N'-tris(2-ethanol)-dihydro-fluoride is a cationic antimicrobial which can have beneficial effects on plaque formation. Here, we determine changes in pellicle and bacterial cell surface properties of the strains Actinomyces naeslundii HM1, Streptococcus mutans NS, S.mutans ATCC 700610, S. sobrinus HG1025 and S. oralis HM1 upon adsorption of this AmF and accompanying effects on bacterial adhesion and biofilm growth. In vitro pellicles had a zeta potential of -12 mV that became less negative upon adsorption of AmF. The chemical functionalities in which carbon and oxygen were involved changed after AmF adsorption and AmF-treated pellicles had a greater surface roughness than untreated pellicles. Water contact angles in vitro decreased from 56 to 45 degrees upon AmF treatment, which corresponded with water contact angles (44 degrees ) measured intraorally on the front incisors of volunteers immediately after using an AmF-containing toothpaste. All bacterial strains were negatively charged and their isoelectric points (IEP) increased upon AmF adsorption. Minimal inhibitory concentrations were smallest for strains exhibiting the largest increase in IEP. Adhesion to salivary pellicles and biofilm growth of the mutans streptococcal strains were significantly reduced after AmF treatment, but not of A. naeslundii or S. oralis. However, regardless of the strain involved, biofilm viability decreased significantly after AmF treatment. The electrostatic interaction between cationic AmF and negatively charged bacterial cell surfaces is pivotal in establishing reduced biofilm formation by AmF through a combination of effects on initial adhesion and killing. The major effect of AmF treatment, however, was a reduction brought about in biofilm viability.
胺氟化物（AmF）N'-十八烷基-三亚甲基二胺-N，N，N'-三（2-乙醇）-二氢氟化物是一种阳离子抗菌剂，对牙菌斑形成可能具有有益作用。在此，我们确定了该AmF吸附后，内氏放线菌HM1、变形链球菌NS、变形链球菌ATCC 700610、远缘链球菌HG1025和口腔链球菌HM1菌株的薄膜及细菌细胞表面特性的变化，以及对细菌黏附和生物膜生长的伴随影响。体外薄膜的ζ电位为-12 mV，吸附AmF后其负性降低。吸附AmF后，涉及碳和氧的化学官能团发生了变化，且经AmF处理的薄膜比未处理的薄膜具有更大的表面粗糙度。体外水接触角经AmF处理后从56度降至45度，这与志愿者使用含AmF牙膏后立即在前牙上测得的口腔内水接触角（44度）相符。所有细菌菌株均带负电荷，吸附AmF后其等电点（IEP）升高。对于IEP升高幅度最大的菌株，其最小抑菌浓度最小。经AmF处理后，变形链球菌菌株对唾液薄膜的黏附及生物膜生长显著降低，但内氏放线菌或口腔链球菌则不然。然而，无论涉及何种菌株，经AmF处理后生物膜活力均显著降低。阳离子AmF与带负电荷的细菌细胞表面之间的静电相互作用对于通过对初始黏附和杀菌的综合作用来减少AmF形成生物膜至关重要。然而，AmF处理的主要作用是降低生物膜活力。
