Photodynamically Active Electrospun Fibers for Antibiotic-Free Infection Control

Area of Science:

• Biomaterials Science
• Photodynamic Therapy
• Tissue Engineering

Background:

• Rising antibiotic resistance necessitates alternative infection control strategies.
• Antimicrobial biomaterials are crucial for oral soft tissue regeneration and infection management.
• There is a clinical need for on-demand, antibiotic-free antimicrobial biomaterial solutions.

Purpose of the Study:

• To explore the feasibility of integrating bioresorbable electrospun polymer scaffolds with localized antimicrobial photodynamic therapy (aPDT).
• To develop an on-demand, light-activated antimicrobial functionality in polymer fibers.
• To create an antibiotic-free infection control method for tissue regeneration.

Main Methods:

• Electrospinning of poly(ε-caprolactone (PCL) or poly[(rac-lactide)-co-glycolide] (PLGA) fibers encapsulating photosensitizers (methylene blue or erythrosin B).
• Characterization of fiber loading efficiency, microarchitecture (SEM, porometry, BET), tensile properties, and hydrolytic behavior.
• In vitro assessment of antimicrobial photodynamic therapy (aPDT) effect against Escherichia coli.

Main Results:

• Successfully fabricated PCL and PLGA fibrous scaffolds with ~100 wt% photosensitizer loading efficiency.
• Encapsulation increased tensile modulus and reduced fiber diameter and pore size.
• Visible light exposure of photosensitizer-loaded PCL fibers reduced Escherichia coli viability by over 1 log, while controls showed no effect.

Conclusions:

• Photosensitizer-encapsulated electrospun fibers demonstrate effective on-demand, antibiotic-free antimicrobial photodynamic therapy.
• These materials hold significant potential for localized infection control in regenerative medicine applications.
• The developed approach offers a flexible, commercially viable alternative to traditional antibiotics.