Dong Xiuli, Overton Christopher M, Tang Yongan, Darby Jasmine P, Sun Ya-Ping, Yang Liju
Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise (BRITE), North Carolina Central University, Durham, NC, United States.
Department of Chemistry, Clemson University, Clemson, SC, United States.
Front Bioeng Biotechnol. 2021 Nov 18;9:786077. doi: 10.3389/fbioe.2021.786077. eCollection 2021.
This study aimed to address the significant problems of bacterial biofilms found in medical fields and many industries. It explores the potential of classic photoactive carbon dots (CDots), with 2,2'-(ethylenedioxy)bis (ethylamine) (EDA) for dot surface functionalization (thus, EDA-CDots) for their inhibitory effect on biofilm formation and the inactivation of cells within established biofilm. The EDA-CDots were synthesized by chemical functionalization of selected small carbon nanoparticles with EDA molecules in amidation reactions. The inhibitory efficacy of CDots with visible light against biofilm formation was dependent significantly on the time point when CDots were added; the earlier the CDots were added, the better the inhibitory effect on the biofilm formation. The evaluation of antibacterial action of light-activated EDA-CDots against planktonic cells the cells in biofilm indicate that CDots are highly effective for inactivating planktonic cells but barely inactivate cells in established biofilms. However, when coupling with chelating agents (e.g., EDTA) to target the biofilm architecture by breaking or weakening the EPS protection, much enhanced photoinactivation of biofilm-associated cells by CDots was achieved. The study demonstrates the potential of CDots to prevent the initiation of biofilm formation and to inhibit biofilm growth at an early stage. Strategic combination treatment could enhance the effectiveness of photoinactivation by CDots to biofilm-associated cells.
本研究旨在解决医学领域和许多行业中发现的细菌生物膜的重大问题。它探索了经典的光活性碳点（CDots），用2,2'-（乙二氧基）双（乙胺）（EDA）对碳点表面进行功能化（即EDA-CDots），以研究其对生物膜形成的抑制作用以及对已形成生物膜内细胞的灭活作用。通过在酰胺化反应中用EDA分子对选定的小碳纳米颗粒进行化学功能化来合成EDA-CDots。可见光下CDots对生物膜形成的抑制效果显著取决于添加CDots的时间点；添加CDots越早，对生物膜形成的抑制效果越好。对光激活的EDA-CDots对浮游细胞和生物膜内细胞的抗菌作用评估表明，CDots对浮游细胞的灭活非常有效，但对已形成生物膜内的细胞几乎没有灭活作用。然而，当与螯合剂（如EDTA）结合以通过破坏或削弱EPS保护来靶向生物膜结构时，CDots对生物膜相关细胞的光灭活作用大大增强。该研究证明了CDots在预防生物膜形成起始和早期抑制生物膜生长方面的潜力。策略性联合治疗可以提高CDots对生物膜相关细胞的光灭活效果。
