Development of Meso-Substituted Heterocyclic BODIPY-Based Polymeric Nanoparticles for Pathogen Inhibition using Photodynamic Therapy

In this work, a series of novel small fluorophores, meso-substituted heterocyclic BODIPYs were designed and synthesized as phototherapeutic agents. Boron dipyrromethene (BODIPY) dyes are promising chromophores and currently used as a sensitizers in photodynamic therapy (PDT). However, BODIPY as an organic photosensitizer (PS), suffers from poor hydrophilicity resulting in low efficiency in biological applications. To overcome these problems, biopolymer (gelatin) based nanoparticles are developed to incorporate BODIPYs, to achieve phototherapeutic nanoagents (BODIPY-GNPs) in the aqueous system. More importantly, BODIPY-GNPs have better in vitro physicochemical properties in the aqueous medium than native BODIPYs. The BODIPY-GNPs were further explored for their photo-inhibition activity towards Gram-positive and Gram-negative bacteria and fungi using LED as the light source. These BODIPY molecules also showed the ability to intercalate the DNA in vitro. This study provides a new avenue to design therapeutic agents for biomedical applications in photodynamic therapy.

Automated summary

This work designs and synthesizes a series of novel small fluorophores called meso-substituted heterocyclic BODIPYs as phototherapeutic agents. To improve the efficiency in biological applications, biopolymer-based nanoparticles (BODIPY-GNPs) are developed to incorporate BODIPYs in the aqueous system. The BODIPY-GNPs exhibit better physicochemical properties and show photo-inhibition activity towards bacteria and fungi, as well as the ability to intercalate DNA. This study provides a new avenue for designing therapeutic agents in photodynamic therapy.