Horev Benjamin, Klein Marlise I, Hwang Geelsu, Li Yong, Kim Dongyeop, Koo Hyun, Benoit Danielle S W
†Department of Biomedical Engineering, ‡Center for Oral Biology, ⊥Department of Chemical Engineering, and #Center of Musculoskeletal Research, University of Rochester, Rochester, New York 14627, United States.
§Biofilm Research Lab, Levy Center for Oral Health, and ∥Department of Orthodontics and Divisions of Pediatric Dentistry and Community Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
ACS Nano. 2015 Mar 24;9(3):2390-404. doi: 10.1021/nn507170s. Epub 2015 Feb 13.
Development of effective therapies to control oral biofilms is challenging, as topically introduced agents must avoid rapid clearance from biofilm-tooth interfaces while targeting biofilm microenvironments. Additionally, exopolysaccharides-matrix and acidification of biofilm microenvironments are associated with cariogenic (caries-producing) biofilm virulence. Thus, nanoparticle carriers capable of binding to hydroxyapatite (HA), saliva-coated HA (sHA), and exopolysaccharides with enhanced drug release at acidic pH were developed. Nanoparticles are formed from diblock copolymers composed of 2-(dimethylamino)ethyl methacrylate (DMAEMA), butyl methacrylate (BMA), and 2-propylacrylic acid (PAA) (p(DMAEMA)-b-p(DMAEMA-co-BMA-co-PAA)) that self-assemble into ∼21 nm cationic nanoparticles. Nanoparticles exhibit outstanding adsorption affinities (∼244 L-mmol(-1)) to negatively charged HA, sHA, and exopolysaccharide-coated sHA due to strong electrostatic interactions via multivalent tertiary amines of p(DMAEMA). Owing to hydrophobic cores, nanoparticles load farnesol, a hydrophobic antibacterial drug, at ∼22 wt %. Farnesol release is pH-dependent with t1/2 = 7 and 15 h for release at pH 4.5 and 7.2, as nanoparticles undergo core destabilization at acidic pH, characteristic of cariogenic biofilm microenvironments. Importantly, topical applications of farnesol-loaded nanoparticles disrupted Streptococcus mutans biofilms 4-fold more effectively than free farnesol. Mechanical stability of biofilms treated with drug-loaded nanoparticles was compromised, resulting in >2-fold enhancement in biofilm removal under shear stress compared to free farnesol and controls. Farnesol-loaded nanoparticles effectively attenuated biofilm virulence in vivo using a clinically relevant topical treatment regimen (2×/day) in a rodent dental caries disease model. Strikingly, treatment with farnesol-loaded nanoparticles reduced both the number and severity of carious lesions, while free farnesol had no effect. Nanoparticle carriers have great potential to enhance the efficacy of antibiofilm agents through multitargeted binding and pH-responsive drug release due to microenvironmental triggers.
开发有效的疗法来控制口腔生物膜具有挑战性，因为局部引入的药物必须在靶向生物膜微环境的同时避免从生物膜-牙齿界面快速清除。此外，胞外多糖基质和生物膜微环境的酸化与致龋（产生龋齿）生物膜的毒力有关。因此，开发了能够与羟基磷灰石（HA）、唾液包被的HA（sHA）和胞外多糖结合并在酸性pH下增强药物释放的纳米颗粒载体。纳米颗粒由二嵌段共聚物形成，该共聚物由甲基丙烯酸2-（二甲氨基）乙酯（DMAEMA）、甲基丙烯酸丁酯（BMA）和2-丙基丙烯酸（PAA）（p（DMAEMA）-b-p（DMAEMA-co-BMA-co-PAA））组成，它们自组装成约21 nm的阳离子纳米颗粒。由于通过p（DMAEMA）的多价叔胺产生的强静电相互作用，纳米颗粒对带负电荷的HA、sHA和胞外多糖包被的sHA表现出出色的吸附亲和力（约244 L·mmol⁻¹）。由于具有疏水核心，纳米颗粒以约22 wt%的含量负载法尼醇，一种疏水抗菌药物。法尼醇的释放是pH依赖性的，在pH 4.5和7.2下释放的t1/2分别为7小时和15小时，因为纳米颗粒在酸性pH下会发生核心不稳定，这是致龋生物膜微环境的特征。重要的是，负载法尼醇的纳米颗粒的局部应用破坏变形链球菌生物膜的效果比游离法尼醇有效4倍。用负载药物的纳米颗粒处理的生物膜的机械稳定性受到损害，与游离法尼醇和对照相比，在剪切应力下生物膜去除率提高了2倍以上。在啮齿动物龋齿疾病模型中，使用临床相关的局部治疗方案（每天2次），负载法尼醇的纳米颗粒在体内有效地减弱了生物膜的毒力。令人惊讶的是，用负载法尼醇的纳米颗粒治疗减少了龋损的数量和严重程度，而游离法尼醇则没有效果。由于微环境触发因素，纳米颗粒载体具有通过多靶点结合和pH响应性药物释放来提高抗生物膜药物疗效的巨大潜力。
