Antimicrobial Fe₂O₃-CuO-P₂O₅ glasses.

Area of Science:

• Materials Science
• Inorganic Chemistry
• Biomedical Engineering

Background:

• Fomite-mediated transmission of infectious diseases is a significant concern in high-risk settings.
• Existing antimicrobial materials may lack the necessary durability for demanding applications.
• The Fe2O3-CuO-P2O5 ternary system was explored for developing durable antimicrobial glasses.

Purpose of the Study:

• To develop glasses with high antimicrobial efficacy for mitigating disease transmission.
• To enhance the chemical durability of antimicrobial glasses through the addition of Fe2O3.
• To investigate the relationship between glass composition, durability, and antimicrobial properties.

Main Methods:

• Synthesis of glasses in the Fe2O3-CuO-P2O5 ternary system.
• Evaluation of chemical durability and copper ion leaching.
• Antimicrobial efficacy testing using log kill assays.
• Ab-initio molecular dynamics simulations to understand structural properties.

Main Results:

• Addition of Fe2O3 significantly increased glass chemical durability, reducing copper leachate by over 3 orders of magnitude.
• The highest Fe2O3 content, while maximizing durability, resulted in antimicrobial efficacy below the target log kill.
• Molecular dynamics simulations indicated increased network connectivity with higher Fe2O3 content.
• Experimental results confirmed Fe2O3 content, not CuO, dictates copper release and antimicrobial activity.

Conclusions:

• Fe2O3 addition is crucial for enhancing the durability of CuO-P2O5 based antimicrobial glasses.
• A balance between Fe2O3 content for durability and CuO content for antimicrobial efficacy is necessary.
• The amount of leached copper, rather than its oxidation state, is the primary driver of antimicrobial activity.