Although phagocytosis serves as the front line to attack invading pathogens, its low bacterial encounter and killing rates leads to an ineffective bactericidal output. In view of this, developing multifunctional theranostic probe to effectively discriminate and ablate intracellular bacteria is highly desirable. However, the shielding effect of the host macrophages put the detection and elimination of macrophage-engulfed bacteria into a challenging task. Herein, we utilize a luminogen with aggregation-induced emission (AIE) characteristics, namely TTVP, as a simple and effective probe for simultaneous tracing and photodynamic killing of intracellular Gram-positive bacteria. With the help of the AIE property, excellent water solubility, near-infrared (NIR) emission and strong reactive oxygen species (ROS) generating ability, TTVP performed ideally to be a targeting agent to intracellular Gram-positive bacteria with high signal contrast, as well as to be a photosensitizer to effectively ablate intracellular bacteria without attacking host macrophages. This work thus provides insights for the next generation antibiosis theranostic application for potential clinical trials.

尽管吞噬作用是攻击入侵病原体的前线，但其低细菌接触率和杀灭率导致无效的杀菌输出。鉴于此，非常需要开发一种能有效区分和消融细胞内细菌的多功能治疗试剂。但是，宿主巨噬细胞的屏蔽作用使巨噬细胞吞噬细菌的检测和消除成为一项艰巨的任务。本文中，我们利用具有聚集诱导发射（AIE）特性的发光剂，即TTVP，作为同时追踪和光动力杀死细胞内革兰氏阳性细菌的简单有效探针。借助AIE特性，出色的水溶性，近红外（NIR）发射和强大的活性氧（ROS）生成能力，TTVP理想地用作具有高信号对比度的细胞内革兰氏阳性细菌的靶向剂，并且是光敏剂以有效消融细胞内细菌而不会攻击宿主巨噬细胞。因此，这项工作为潜在的临床试验提供了下一代抗菌治疗学应用的见识。