Persistent Luminescence‐Based Theranostics for Real‐Time Monitoring and Simultaneously Launching Photodynamic Therapy of Bacterial Infections

Abstract

External light irradiation is usually required in bacterial infection theranostics; however, it is always accompanied by limited light penetration, imaging interference, and incomplete bacterial destruction. Herein, a feasible “image‐launching therapy” strategy is developed to integrate real‐time optical imaging and simultaneous photodynamic therapy (PDT) of bacterial infections into persistent luminescence (PL) nanoparticles (NPs). Mesoporous silica NPs are used as a substrate for in situ deposition of PL nanodots of ZnGa2O4:Cr3+ to obtain mPL NPs, followed by surface grafting with silicon phthalocyanine (Si‐Pc) and electrostatic assembly of cyanine 7 (Cy7) to fabricate mPL@Pc‐Cy NPs. The PL emission of light‐activated mPL@Pc‐Cy NPs is quenched by Cy7 assembly at physiological conditions through the fluorescence resonance energy transfer effect, but is rapidly restored after disassembly of Cy7 in response to bacterial infections. The self‐illuminating capabilities of NPs avoid tissue autofluorescence under external light irradiation and achieve real‐time colorimetric imaging of bacterial infections. In addition, the afterglow of mPL NPs can persistently excite Si‐Pc photosensitizers to promote PDT efficacy for bacterial elimination and accelerate wound full recovery with normal histologic features. Thus, this study expands the theranostic strategy for precise imaging and simultaneous non‐antibiotic treatment of bacterial infections without causing side effects to normal tissues.

Self-Driven Electron Transfer Biomimetic Enzymatic Catalysis of Bismuth-Doped PCN-222 MOF for Rapid Therapy of Bacteria-Infected Wounds

“…2 Wound infection occurs after pathogenic bacteria (usually Staphylococcus aureus (S. aureus)) invade the damaged tissues, and these wounds provide a nourishing environment for the growth of microorganisms. 3 In general, clinical symptoms such as redness, suppuration, and tissue damage will greatly increase when the bacterial load in 1 g of tissue exceeds 10 5 colony forming units (CFU). 4 This in turn triggers an increase inflammatory oxidative stress, which then impedes the natural progression of healing and reduces the effectiveness of wound healing.…”

Smart microneedle patches for wound healing and management

“…13,37 Next-generation wound dressings that are capable of real-time monitoring, early diagnosis, and on-demand therapy have received a lot of attention to overcome the woundhealing process's ''black box'' status. [38][39][40] Injured tissue generates exudate, a fluid rich in proteins such as electrolytes, creatinine, fibrinogen, matrix metalloproteinases (MMPs) and c-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-a). 41,42 Additionally, certain physical wound environment factors, such as temperature, pH, humidity, and exercise, influence wound healing.…”

Antimicrobial Photodynamic Therapy for the Remote Eradication of Bacteria

“…More significantly, IR 820-DAA displayed outstanding wound healing in MRSA-infected mouse, with negligible consequences at the given dose. [166] Interestingly, there has been more intelligent approaches whereby researchers are looking at nanoparticles such as upconversion nanoparticles (UCNPs) [98,179] and persistent-luminescence nanoparticles (PL-NPs) [180,181] and to serve as light sources to excite the photosensitizers in a cascade manner, that has been applied in wound healing animal models.…”

“…Similarly, in vivo studies showed that mPL@PcÀ Cy NPs could inactivate S. aureus with an antibacterial rate of over 99.5 %, with a wound recovery of 61.3 %. [180]…”

“…Copyright (2021), with permission from WILEY-VCH GmbH; (E) A continuous irradiation nanoplatform for simultaneous photodynamic therapy and imaging with persistent luminescence (PL) nanoparticles. Reproduced from ref [180]. Copyright (2022), with permission from WILEY-VCH GmbH.…”