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Published on: January 24, 2025
Optimization and utilization of single chain metallocatanionic vesicles for antibacterial photodynamic therapy (aPDT)
Bunty Sharma1, Gurpreet Kaur1, Ganga Ram Chaudhary1
1Department of Chemistry and Centre of Advanced Studies in Chemistry, Panjab University, Chandigarh, India. gurpreet14@pu.ac.in grc22@pu.ac.in.
Abstract:
Currently, bacterial infection due to multi-drug-resistant bacteria is one of the foremost problems in public health. Photodynamic therapy plays a significant role against bacterial infection, without causing any side effects. But the photosensitizers are associated with many drawbacks, which lessen their photodynamic efficiency. In this context, the current study describes the synthesis of new metallocatanionic vesicles and employs them in photodynamic therapy. These vesicles were synthesized by using a single-chain cationic metallosurfactant (CuCPC I) and sodium oleate (NaOl) as an anionic component. These vesicles were characterized from conductivity, dynamic light scattering, zeta potential, field emission scanning electron microscopy, and confocal microscopy measurements. Methylene blue (MB) was used as a photosensitizer and its singlet oxygen quantum yield in the presence of these vesicles was determined by irradiating with 650 nm wavelength laser light. These vesicles play a dual-functional role, one helping in delivering the photosensitizer and the second doubling their singlet oxygen production capability due to the presence of metal ions. Antibacterial photodynamic therapy (aPDT) was studied against E. coli bacteria (Gram-negative bacteria). These vesicles also inherit their antibacterial activity and MB-encapsulated metallocatanionic vesicles on irradiation have shown 100% killing efficiency. In summary, we offer metallocatanionic vesicles prepared via a facile approach, which encapsulate a photosensitizer and can be used to combat E. coli infection through photodynamic therapy. We envisage that these synthesized metallocatanionic vesicles will provide a new modification to the catanionic mixture family and could be used for various applications in the future.
Insights
New metallocatanionic vesicles effectively deliver photosensitizers for enhanced antibacterial photodynamic therapy (aPDT). These metal-containing vesicles significantly boost singlet oxygen production, achieving 100% bacterial killing efficiency against E. coli.
Area of Science:
- Materials Science
- Nanotechnology
- Biomedical Engineering
Background:
- Multi-drug-resistant bacterial infections pose a significant global health challenge.
- Photodynamic therapy (PDT) offers a side-effect-free approach to combatting bacterial infections.
- Limitations in photosensitizer efficiency hinder the full potential of PDT.
Purpose of the Study:
- To synthesize novel metallocatanionic vesicles for enhanced photodynamic therapy.
- To investigate the role of these vesicles in photosensitizer delivery and singlet oxygen generation.
- To evaluate the efficacy of the developed system against E. coli using antibacterial photodynamic therapy (aPDT).
Main Methods:
- Synthesis of metallocatanionic vesicles from a cationic metallosurfactant and sodium oleate.
- Characterization using conductivity, dynamic light scattering, zeta potential, SEM, and confocal microscopy.
- Determination of singlet oxygen quantum yield of methylene blue (MB) within the vesicles under laser irradiation.
- Assessment of antibacterial activity against E. coli via aPDT.
Main Results:
- Metallocatanionic vesicles were successfully synthesized and characterized.
- The vesicles demonstrated a dual role: photosensitizer delivery and enhanced singlet oxygen production.
- MB-encapsulated vesicles achieved 100% killing efficiency against E. coli upon irradiation.
- The metal ions within the vesicles amplified singlet oxygen generation.
Conclusions:
- Facile synthesis of metallocatanionic vesicles provides a novel platform for PDT.
- These vesicles enhance photosensitizer performance and exhibit inherent antibacterial properties.
- The developed system offers a promising strategy for combating E. coli infections through aPDT.
