Membrane‐Anchoring Photosensitizer with Aggregation‐Induced Emission Characteristics for Combating Multidrug‐Resistant Bacteria

Abstract

Traditional photosensitizers (PSs) show reduced singlet oxygen (1O2) production and quenched fluorescence upon aggregation in aqueous media, which greatly affect their efficiency in photodynamic therapy (PDT). Meanwhile, non‐targeting PSs generally yield low efficiency in antibacterial performance due to their short lifetimes and small effective working radii. Herein, a water‐dispersible membrane anchor (TBD‐anchor) PS with aggregation‐induced emission is designed and synthesized to generate 1O2 on the bacterial membrane. TBD‐anchor showed efficient antibacterial performance towards both Gram‐negative (Escherichia coli) and Gram‐positive bacteria (Staphylococcus aureus). Over 99.8 % killing efficiency was obtained for methicillin‐resistant S. aureus (MRSA) when they were exposed to 0.8 μm of TBD‐anchor at a low white light dose (25 mW cm−2) for 10 minutes. TBD‐anchor thus shows great promise as an effective antimicrobial agent to combat the menace of multidrug‐resistant bacteria.

Beyond Antibiotics: Photo/Sonodynamic Approaches for Bacterial Theranostics

“…A representative example was reported by Liu’s group who designed the AIE photosensitizer with D (donor)-A’ (auxiliary acceptor)-π (π spacer)-A (acceptor) structure, while three cationic groups were involved in the molecular design for bacterial membrane anchoring (Fig. 5 a–g) [ 71 ]. With a high 1 O 2 quantum yield of 0.48, this novel AIE photosensitizer showed efficient antibacterial performance toward both Gram-positive bacteria ( S. aureus ) and Gram-negative ( E. coli ).…”

“…Confocal laser scanning microscopy (CLSM) images of E. coli treated with 10 μM membrane-anchoring AIE photosensitizer and then labeled in b false green color by DAPI, c red color by photosensitizer, d yellow color by overlay images. Scanning electron microscopy images of e blank E. coli , f E. coli + 10 μM AIE photosensitizer under dark condition, g E. coli + 10 μM AIE photosensitizer under white-light irradiation [ 71 ]. Copyright 2019 Wiley-VCH.…”

Insights and Perspectives Regarding Nanostructured Fluorescent Materials toward Tackling COVID-19 and Future Pandemics

“…For example, Chen et al. 246 have designed an AIE-based membrane-anchoring photosensitizer containing a phenyl ring with three cationic groups that can effectively penetrate into the MRSA membrane and kill them through a PDT effect. Figure 11 A shows that a low dose of this AIE photosensitizer is effective for a PDT under a low-power light irradiation.…”

“… (A) Effect of concentration of an AIE photosensitizer (left) and the intensity of white light irradiation (right) on the PDT performance of the membrane anchoring the AIE-PS for the treatment of MRSA. Reproduced with permission from ref ( 246 ). Copyright 2020 John Wiley and Sons.…”

Poly(p-phenylenevinylene) nanoparticles modified with antiEGFRvIII for specific glioblastoma therapy

“…Photodynamic therapy (PDT), as a non-invasive therapeutic manner, has attracted increasingly wide attention because of its low side-effects and high efficiency 14 – 16 . Conjugated polymers with characteristic delocalized π-electronic backbones have drawn increasing research interests due to their strong light absorption capacity, high photostability and low cytotoxicity 17 – 23 . To date, a great number of conjugated polymers have been designed and synthesized to be used as photosensitizers in PDT 24 – 29 .…”