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Updated: Aug 5, 2026
Antimicrobial Characterization of Advanced Materials for Bioengineering Applications
Published on: August 4, 2018
Development and characterization of photo-responsive antimicrobial resins
Maria Luisa Leite1, Sherri Sadr Karimi2, Nancy Zhai2
1Department of Oral Health Sciences, Faculty of Dentistry, The University of British Columbia, Vancouver, BC, Canada; College of Dentistry, University of Saskatchewan, Saskatoon, SK, Canada; Advancing Multifunctional Dental Biomaterials Research Excellence Cluster, The University of British Columbia, Vancouver, BC, Canada.
Objectives:
This study investigated natural photosensitizers as candidates for developing photo-responsive antimicrobial dental resins. Evaluation of their physicochemical properties, followed by assessment of antimicrobial and cytotoxic effects under photodynamic therapy (PDT), was conducted.
Methods:
Curcumin, riboflavin, retinoic acid, and safranal were first assessed for singlet oxygen production and antimicrobial potential against Streptococcus mutans and Candida albicans under blue-light PDT (440-460 nm, 22.55 mW/cm²; 0, 20.25, 40.5, 81.0 J/cm²). Based on these results, curcumin (Cur) and/or riboflavin (B2) were incorporated into an experimental dental resin (EDR) at 0.00, 0.05, or 0.1 wt%. Physicochemical properties, including thermogravimetric analysis, degree of conversion (DC), water sorption (WS), solubility (SL), flexural strength (FS) and shear bond strength (SBS) at 24 h and 6 months. Antimicrobial efficacy against dual-species biofilms (S. mutans/C. albicans) was tested immediately and after 6 months, with or without PDT (40.5 J/cm²). Cytotoxicity was assessed using gingival epithelial cells (extract test) and odontoblast-like cells (transdentinal test), with or without PDT (40.5 J/cm²).
Results:
Photosensitizer-loaded EDRs showed no adverse effects on DC, WS, or SL. Improved FS after aging was observed for B2-containing formulations, while SBS remained stable except for the 0.1% Cur group. All photosensitizer-loaded EDRs exhibited long-lasting antimicrobial activity when combined with PDT. Cytotoxicity was formulation-dependent, with only the highest Cur + B2 concentration showing adverse effects when combined with PDT.
Significance:
These findings demonstrate the feasibility of photo-responsive dental resins for sustained, on-demand antimicrobial activity. Notably, 0.1% B2-loaded EDR combined with PDT showed optimal antimicrobial efficacy, biocompatibility, and physicochemical performance.
