【作者】 陈佳文； 张红； 张志民；

【Author】 Jiawen Chen;Hong Zhang;Zhimin Zhang;Department of Endodontics,Jilin Provincial Key Laboratory of Oral Biomedical Engineering,School and Hospital of Stomatology,Jilin University;

【机构】 吉林省口腔生物医学工程重点实验室,吉林大学口腔医院牙体牙髓病科；

【摘要】 目的:本研究利用沸石咪唑框架ZIF-8负载CaO₂及光敏剂二氢卟吩e6,包裹聚醚酰亚胺（PEI）形成新型纳米平台。该平台旨在解决光敏剂与细菌之间作用弱及光敏剂在根管系统缺氧微环境中作用受限的问题。方法:通过在CaO₂表面原位形成ZIF-8,随后在其表面负载二氢卟吩e6并包裹PEI,得到最终产物Ce6/CaO₂/ZIF-8@PEI。合成Ce6/ZIF-8@PEI作为对照组。通过X射线能谱（EDS）、紫外-可见光光谱（UV-vis）、Zeta电位仪及氧指示探针（[Ru（dpp）₃]Cl₂）对材料进行表征。通过滴板计数法评价材料抗粪肠球菌性能,并使用扫描电镜观察细菌的形态变化。使用活/死染色法检测材料抗粪肠球菌生物膜的活性。通过CCK-8法评价其对小鼠成纤维细胞（L929）的毒性。结果:不同的表征结果证实Ce6/CaO₂/ZIF-8@PEI成功合成,其具有表面正电位,且能够产生氧气。CFU计数表明与Ce6/ZIF-8@PEI组相比,Ce6/CaO₂/ZIF-8@PEI在5分钟的660 nm光照下具有强大的抗粪肠球菌性能（P<0.05）。SEM图像显示细菌严重受损,细胞变形、破裂,伴有内容物流出。活/死染色显示Ce6/CaO₂/ZIF-8@PEI在光照下具有强大的抗生物膜作用。该材料具有良好的生物相容性,在87.5μg/mL的浓度下L929细胞存活率超80%。结论:Ce6/CaO₂/ZIF-8@PEI能够产生足够的氧气,提高光敏剂Ce6的抗菌效率,且毒性低,是一种有前景的适用于缺氧根管系统的改良光敏剂。更多还原

【Abstract】 Objective:This study designed a novel nanoplatform consisting of zeolite imidazolium framework ZIF-8 loaded with CaO₂ and chlorin e6 and afterwards encapsulated with polyetherimide（PEI）.This nanoplatform aimed to solve the problems of weak interaction between the photosensitizer and bacteria and the restricted efficacy of photosensitizers in the hypoxic microenvironment within the root canal systems.Method:The Ce6/CaO₂/ZIF-8@PEI was synthesized by in situ construction of ZIF-8 on the surface of CaO₂,followed by loading of Ce6 and encapsulation of PEI.Ce6/ZIF-8@PEI nanoparticles were synthesized as control.The nanoparticles were characterized by EDS,UV-vis spectrophotometer,Zeta potential analyzer,and an oxygen indicator probe（[Ru（dpp）₃]Cl₂）.The anti-E.faecalis capabilities were assessed by drop plate method,and the bacterial morphological changes were observed using SEM.Live/Dead assay was conducted to determine the anti-biofilm activity.The cytotoxicity to L929 was determined by CCK-8 assay.Result:Various characterization confirmed the successful synthesis of Ce6/CaO₂/ZIF-8@PEI,which demonstrated a positively charged surface and the ability to generate oxygen.The counting of colony-forming units showed that Ce6/CaO₂/ZIF-8@PEI had potent antibacterial activity under 5-minute 660 nm light irradiation in comparison to the Ce6/ZIF-8@PEI group.SEM images depicted severe cell damage,with cell deformities and even partial lysis,accompanied by content leakage.Live/Dead assay revealed a potent anti-biofilm effect of Ce6/CaO₂/ZIF-8@PEI.The cytocompatibility of Ce6/CaO₂/ZIF-8@PEI was found to be satisfactory,with L929 cell viability exceeding 80% at a concentration of 87.5 μg/mL.Conclusion:Ce6/CaO₂/ZIF-8@PEI,with satisfactory cytocompatibility,was capable of generating sufficient oxygen to boost the antibacterial efficiency of Ce6,making it a promising modified photosensitizer suitable for hypoxic root canal systems.更多还原