Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Meilong Road No. 130, Shanghai 200237, PR China.
Biomater Sci. 2022 Jul 26;10(15):4235-4242. doi: 10.1039/d2bm00780k.
Photodynamic inactivation of bacteria has emerged as a promising antibacterial strategy due to its high antibacterial activity and low bacterial resistance. Herein, an acid-triggered photodynamic antibacterial nanoplatform (IBPAAs) was constructed by co-assembly of an acid-triggered photosensitizer BODIPY (I-NBDP) and the POEGMA--PDEAEMA block copolymer for enhancing the antibacterial efficacy and biofilm-dissipation capability. IBPAAs could have great biocompatibility and stability by the formation of self-assemblies, and it could be cleaved to release the I-NBDP photosensitizer under a dual-step acidic response due to the protonation of the diethylamino groups on both I-NBDP and the POEGMA--PDEAEMA block copolymer. On the one hand, the photoinduced electron transfer (PET) of I-NBDP in IBPAAs under neutral conditions could be attenuated, resulting in an increase of its O yield, effectively improving its photodynamic antibacterial efficacy. On the other hand, the protonation of IBPAAs made it easier to target negatively charged bacterial surfaces, further enhancing its photodynamic antibacterial activity. The antibacterial experiments showed that the IBPAAs assemblies had great photodynamic antibacterial efficacy and biofilm dissipation capability, and it could effectively relieve bacterial infection of wounds and accelerate wound healing . Therefore, this acid-triggered strategy is expected to provide a new path for enhanced photodynamic antibacterial therapy.
光动力细菌灭活因其高抗菌活性和低细菌耐药性而成为一种很有前途的抗菌策略。本文通过将酸响应型光敏剂 BODIPY（I-NBDP）与 POEGMA-PDEAEMA 嵌段共聚物共组装，构建了一种酸触发的光动力抗菌纳米平台（IBPAAs），以增强抗菌功效和生物膜消散能力。IBPAAs 可以通过自组装形成具有良好的生物相容性和稳定性，并且可以在两步酸性响应下被裂解，释放出光敏剂 I-NBDP，这是由于 I-NBDP 和 POEGMA-PDEAEMA 嵌段共聚物上的二乙氨基都被质子化。一方面，IBPAAs 中的 I-NBDP 在中性条件下的光诱导电子转移（PET）可以被削弱，从而增加其 O 产量，有效提高其光动力抗菌功效。另一方面，IBPAAs 的质子化使其更容易靶向带负电荷的细菌表面，进一步增强其光动力抗菌活性。抗菌实验表明，IBPAAs 组装体具有很强的光动力抗菌功效和生物膜消散能力，能有效缓解伤口细菌感染并加速伤口愈合。因此，这种酸触发策略有望为增强光动力抗菌治疗提供新途径。
