Synthesis, Characterization, and Bioactivity of Mesoporous Bioactive Glass Codoped with Zinc and Silver
Tsung-Ying Yang1,2,3,4, Guann-In Chern5, Wei-Hsun Wang6,7,8,9,10,11
1Department of Medical Laboratory Science, I-Shou University, Kaohsiung 84001, Taiwan.
Abstract:
Due to the overconsumption of antimicrobials, antibiotic-resistant bacteria have become a critical health issue worldwide, especially methicillin-resistant S. aureus (MRSA) and vancomycin-resistant E. faecalis (VRE). Recently, many efforts have been made to load metals into bioactive glasses to enhance the multifunctionality of materials, such as antibacterial and osteoinductive functions. Zinc has been documented to stimulate the gene expression of various regulatory factors in bone cells. Meanwhile, previous studies have reported that silver and zinc could be a promising antibacterial combination with synergistic antimicrobial effects. Here, we sought to develop a biomaterial coreleasing zinc and silver, designated 80S-ZnAg, and to evaluate its antibacterial activity and biocompatibility. The textural analyses demonstrated different coreleasing patterns of zinc and silver for the materials. The chemical characterization revealed that the zinc in 80S-ZnAg could be the network modifier when its molar ratio was high, releasing more zinc; zinc could also be the network former when its molar ratio was low, showing an extremely low rate of release. However, the ICP results for 80S-Zn3Ag2 demonstrated up to 7.5 ppm of zinc and 67.6 ppm of silver. Among all the 80S-ZnAg materials, 80S-Zn3Ag2 demonstrated more marked antibacterial activity against MRSA and VRE than the others, with inhibition zones of 11.5 and 13.4 mm, respectively. The cytotoxicity assay exhibited nearly 90% cell viability at 20 mg/mL of 80-Zn3Ag2. Further clinical study is needed to develop an innovative biomaterial to address the issue of antibiotic resistance.
Insights
This study developed a novel biomaterial combining silver and zinc (80S-ZnAg) to combat antibiotic-resistant bacteria like MRSA and VRE. The 80S-Zn3Ag2 formulation showed significant antibacterial activity and good biocompatibility, offering a promising alternative to traditional antibiotics.
Area of Science:
- Biomaterials Science
- Materials Chemistry
- Infectious Diseases
Background:
- Antibiotic resistance, particularly from methicillin-resistant S. aureus (MRSA) and vancomycin-resistant E. faecalis (VRE), is a global health crisis.
- Bioactive glasses incorporating metals are explored for enhanced antibacterial and osteoinductive properties.
- Silver and zinc exhibit synergistic antimicrobial effects and zinc can stimulate bone cell gene expression.
Purpose of the Study:
- To develop and evaluate a novel biomaterial coreleasing zinc and silver (80S-ZnAg) for antibacterial applications.
- To assess the antibacterial activity and biocompatibility of the developed material against resistant bacterial strains.
- To investigate the influence of zinc's molar ratio on its release pattern and material properties.
Main Methods:
- Synthesis and characterization of 80S-ZnAg biomaterials with varying zinc and silver compositions.
- Textural and chemical analyses to understand metal release mechanisms.
- Inductively Coupled Plasma (ICP) analysis for precise metal ion quantification.
- Antibacterial assays measuring inhibition zones against MRSA and VRE.
- Cytotoxicity assays to evaluate cell viability.
Main Results:
- 80S-ZnAg materials exhibited distinct zinc and silver coreleasing patterns based on composition.
- ICP results for 80S-Zn3Ag2 showed significant zinc (7.5 ppm) and silver (67.6 ppm) release.
- 80S-Zn3Ag2 demonstrated superior antibacterial activity against MRSA (11.5 mm inhibition zone) and VRE (13.4 mm inhibition zone).
- Cytotoxicity assays indicated high cell viability (nearly 90%) for 80S-Zn3Ag2 at 20 mg/mL.
Conclusions:
- The developed 80S-ZnAg biomaterial, particularly 80S-Zn3Ag2, shows potent antibacterial efficacy against critical resistant pathogens.
- The material exhibits favorable biocompatibility, suggesting its potential for clinical applications.
- Further clinical studies are warranted to translate this innovative biomaterial for addressing antibiotic resistance.
