College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, 700 Changcheng Road, 266109 Qingdao, China.
School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, 266003 Qingdao, Shandong, China.
ACS Appl Mater Interfaces. 2023 Oct 18;15(41):47866-47879. doi: 10.1021/acsami.3c05351. Epub 2023 Oct 5.
Ferric phosphate (FePOs) nanoenzymes can express peroxidase (POD) activity under the dual stimulation of an acidic environment and high HO concentrations. In living organisms, this generates reactive oxygen species (ROS) in sites of lesion infection, and thus FePOs nanoenzymes can act as antimicrobial agents. Here, CeO and ZnO were immobilized in a scallop-type FePOs nanoenzyme material loaded with a photosensitizer, indocyanine green, to synthesize a multifunctional cascade nanoparticle system (FePOs-CeO-ZnO-ICG, FCZI NPs). HO concentrations could be adjusted through the ZnO self-activation response to the slightly acidic environment in biofilms, further promoting the release of ROS from the POD-like reaction of FePOs, achieving amplification of oxidative stress, DNA and cell membrane damage, and exploiting the photodynamic/photothermal effects of indocyanine green to enhance the antibiofilm effects. CeO can remove redundant ROS by switching from Ce to Ce valence, enhancing its ability to fight chronic inflammation and oxidative stress and thus promoting the regeneration of tissues around infection. By maintaining the redox balance of normal cells, increasing ROS at the infection site, eliminating redundant ROS, and protecting normal tissues from damage, the synthesized system maximizes the elimination of biofilms and treatment at the infection site. Therefore, this work may pave the way for the application of biocompatible nanoenzymes.
磷酸铁（FePOs）纳米酶在酸性环境和高 HO 浓度的双重刺激下可以表达过氧化物酶（POD）活性。在活生物体中，这会在病变感染部位产生活性氧（ROS），因此 FePOs 纳米酶可以作为抗菌剂。在这里，CeO 和 ZnO 被固定在负载光敏剂吲哚菁绿的扇贝型 FePOs 纳米酶材料中，合成了多功能级联纳米颗粒系统（FePOs-CeO-ZnO-ICG，FCZI NPs）。HO 浓度可以通过 ZnO 对生物膜中微酸性环境的自激活反应来调节，进一步促进 ROS 从 FePOs 的类过氧化物酶反应中释放，实现氧化应激、DNA 和细胞膜损伤的放大，并利用吲哚菁绿的光动力/光热效应增强抗生物膜效应。CeO 可以通过从 Ce 到 Ce 的价态转换来去除多余的 ROS，增强其对抗慢性炎症和氧化应激的能力，从而促进感染周围组织的再生。通过维持正常细胞的氧化还原平衡，增加感染部位的 ROS，消除多余的 ROS，并保护正常组织免受损伤，合成系统最大限度地消除生物膜并在感染部位进行治疗。因此，这项工作可能为生物相容的纳米酶的应用铺平道路。
