Highly Stable and Multifunctional Aza-BODIPY-Based Phototherapeutic Agent for Anticancer Treatment

Area of Science:

• Biomedical Engineering
• Materials Science
• Organic Chemistry

Background:

• Phototherapy is a promising noninvasive tumor treatment.
• Existing near-infrared (NIR) phototherapeutic agents suffer from low efficiency, complex synthesis, and poor stability.
• Developing stable and efficient NIR agents is crucial for clinical translation.

Purpose of the Study:

• To design and synthesize a novel donor-acceptor-donor (D-A-D) type organic phototherapeutic agent (B-3) based on NIR aza-boron-dipyrromethene (aza-BODIPY) dye.
• To enhance photothermal conversion efficiency and singlet oxygen generation.
• To evaluate the efficacy of B-3 nanoparticles (NPs) for synergistic photothermal/photodynamic therapy (PTT/PDT) in tumor treatment.

Main Methods:

• Synthesis of a D-A-D type aza-BODIPY dye (B-3).
• Encapsulation of B-3 into nanoparticles (B-3 NPs) using amphiphilic polymers (DSPE-mPEG5000 and F108).
• Evaluation of photothermal conversion efficiency, singlet oxygen generation, photostability, and RONS resistance.
• In vivo assessment of B-3 NPs for synergistic PTT/PDT in tumor elimination.

Main Results:

• B-3 NPs demonstrated excellent photothermal stability and resistance to reactive oxygen and nitrogen species (RONS).
• Achieved high photothermal conversion efficiency (η = 43.0%) and continuous singlet oxygen generation under single-wavelength light irradiation.
• B-3 NPs effectively eliminated tumors with no recurrence through synergistic PTT/PDT under mild conditions.

Conclusions:

• The developed B-3 NPs represent a promising multifunctional NIR phototherapeutic agent.
• The study provides insights into the photothermal conversion mechanism of small organic compounds.
• This work guides the development of advanced NIR agents for potential clinical applications.