Rational Design of Self-Assembled Cationic Porphyrin-Based Nanoparticles for Efficient Photodynamic Inactivation of Bacteria

Abstract

Bacterial infection has become an urgent health problem in the world. Especially, the evolving resistance of bacteria to antibiotics makes the issue more challenging, and thus new treatments to fight these infections are needed. Antibacterial photodynamic therapy (aPDT) is recognized as a novel and promising method to inactivate a wide range of bacteria with few possibilities to develop drug resistance. However, the photosensitizers (PSs) are not effective against Gram-negative bacteria in many cases. Herein, we use conjugated meso-tetra(4-carboxyphenyl)porphine (TCPP) and triaminoguanidinium chloride (TG) to construct self-assembled cationic TCPP-TG nanoparticles (NPs) for efficient bacterial inactivation under visible light illumination. The TCPP-TG NPs can rapidly adhere to both Gram-negative and Gram-positive bacteria and display promoted singlet oxygen ( 1 O 2 ) generation compared with TCPP under light irradiation. The high local positive charge density of TCPP-TG NPs facilitates the interaction between the NPs and bacteria. Consequently, the TCPP-TG NPs produce an elevated concentration of local 1 O 2 under light irradiation, resulting in an extraordinarily high antibacterial efficiency (99.9999% inactivation of the representative bacteria within 4 min). Furthermore, the TCPP-TG NPs show excellent water dispersity and stability during 4 months of storage. Therefore, the rationally designed TCPP-TG NPs are a promising antibacterial agent for effective aPDT.

Light-Activated Biodegradable Covalent Organic Framework-Integrated Heterojunction for Photodynamic, Photothermal, and Gaseous Therapy of Chronic Wound Infection

“…Moreover, the initial morphology of S. aureus cells is smooth, round, and spherical, but the cells’ exposure to red light led to a melted and wrinkled morphology . These results confirm that TP-Por CON@BNN6 may cause damage to the whole plasma membrane.…”

Effect of Topology on Photodynamic Sterilization of Porphyrinic Metal‐Organic Frameworks

“…The antibacterial performance of MOF‐545 were also compared with that of other TCPP‐containing materials against E. coli (Table S2). MOF‐545 exposed to white LED light (4 mW/cm 2 ) for 20 min can reduce the number of E. coli colonies by 3 log while other TCPP‐containing materials required higher power intensity or longer irradiation time [6d,f,26] . In addition, The MOFs exhibited better photodynamic antibacterial performance for S. aureus than E. coli under the same experimental conditions due to the different cell wall structures of Gram‐negative and Gram‐positive bacteria [5] .…”

Alginate-based aerogels as wound dressings for efficient bacterial capture and enhanced antibacterial photodynamic therapy

“…During the process, irreparable oxidative damage is caused by 1 O 2 to vital cellular components, such as lipids, proteins and DNA, which leads to the death of bacteria with negligible bacterial resistance. Due to its broad-spectrum antibacterial capacity and remote controllability, intensive research attentions have been continuously devoted to aPDT in the past decades (Jia et al., 2017 ; Sun et al., 2019 ; Dharmaratne et al., 2020 ; Li et al., 2020 ; Xiao et al., 2020 ; Feng et al., 2021 ). Fortunately, aPDT in wound dressing platforms does not have the two main drawbacks: inadequate oxygen supply and limited penetration depth of laser light.…”