口腔生物膜是龋齿的主要原因,由于生物膜结构复杂,很难完全根除。更重要的是,生物膜的缺氧环境和常规光敏剂的低水溶性严重制约了光动力疗法(PDT)对生物膜的治疗效果。尽管常规的光敏剂可以装载在纳米载体中,由于聚集引起的猝灭(ACQ)现象,它降低了PDT效应。在这项研究中,我们制造了一种氧自给自足的纳米液滴(PFC/TPA@FND),由氟化聚合物(FP)组成,全氟化碳(PFC)和聚集诱导发射(AIE)光敏剂(三苯胺,TPA),消除口腔细菌生物膜和美白牙齿。通过聚合甲基丙烯酸(二甲基氨基)乙酯合成氟化聚合物,氟化单体和1-壬醇单体。纳米液滴可以质子化并且在细菌生物膜酸性环境下表现出强正电荷,促进纳米液滴深度穿透生物膜。更重要的是,由于氟化聚合物与PFC之间的疏水亲和力可以缓解缺氧环境并增强PDT效应,因此纳米液滴具有极高的PFC和氧负载效率。此外,与常规ACQ光敏剂加载系统相比,由于独特的AIE效应,PFC/TPA@FND在光照射下可以表现出优异的PDT效应来消融口腔细菌生物膜。体内龋齿动物模型证明,纳米液滴可以减少龋齿面积,而不会破坏牙齿结构。离体牙齿美白测定还证实,与商业牙齿增白剂H2O2相比,纳米液滴具有相似的牙齿美白能力,同时不破坏牙齿的表面微结构。这种氧自给自足的纳米液滴为生物医学中的口腔生物膜根除提供了替代视角。
Oral biofilm is the leading cause of dental caries, which is difficult to completely eradicate because of the complicated biofilm structure. What\'s more, the hypoxia environment of biofilm and low water-solubility of conventional photosensitizers severely restrict the therapeutic effect of photodynamic therapy (PDT) for biofilm. Although conventional photosensitizers could be loaded in nanocarriers, it has reduced PDT effect because of aggregation-caused quenching (ACQ) phenomenon. In this study, we fabricated an oxygen self-sufficient nanodroplet (PFC/TPA@FNDs), which was composed of fluorinated-polymer (FP), perfluorocarbons (PFC) and an aggregation-induced emission (AIE) photosensitizer (Triphenylamine, TPA), to eradicate oral bacterial biofilm and whiten tooth. Fluorinated-polymer was synthesized by polymerizing (Dimethylamino)ethyl methacrylate, fluorinated monomer and 1-nonanol monomer. The
nanodroplets could be protonated and behave strong positive charge under bacterial biofilm acid environment promoting
nanodroplets deeply penetrating biofilm. More importantly, the
nanodroplets had extremely high PFC and oxygen loading efficacy because of the hydrophobic affinity between fluorinated-polymer and PFC to relieve the hypoxia environment and enhance PDT effect. Additionally, compared with conventional ACQ photosensitizers loaded system, PFC/TPA@FNDs could behave superior PDT effect to ablate oral bacterial biofilm under light irradiation due to the unique AIE effect. In vivo caries animal model proved the
nanodroplets could reduce dental caries area without damaging tooth structure. Ex vivo tooth whitening assay also confirmed the
nanodroplets had similar tooth whitening ability compared with commercial tooth whitener H2O2, while did not disrupt the surface microstructure of tooth. This oxygen self-sufficient nanodroplet provides an alternative visual angle for oral biofilm eradication in biomedicine.