Antimicrobial bioactive glass-ceramic scaffold

Executive Summary

Healing infected tissue and combating resistant bacteria are significant clinical challenges. Antibiotic-based therapies are increasingly unsuccessful due to the ability of pathogens to develop resistance. Methicillin resistant Staphylococcus aureus (MRSA), for example, is a leading cause of many infections, including skin and soft tissue infections, endocarditis, and osteomyelitis. MSU researchers have developed a new bioactive glass scaffold that has a series of interconnected struts with antibiotic activity. The scaffold promotes proliferation and differentiation of cells that are in contact with it, providing an ideal 3 dimensional template for healthy tissue regeneration including bone tissue. In addition, the antimicrobial nature of the scaffold can treat infections at a implanted location or location at risk of infection.

Description of Technology

This technology is based on a 3 dimensional scaffold system containing silver doped bioactive glass-ceramic microparticles (Ag-BG) ranging from micron down to nanosized. The scaffolds can be prepared by a variety of methods including a) impregnating a 3 dimensional foam template with a slurry mixture containing the scaffold ingredients, then drying and sintering to make the scaffold, b) preparing a polymer based filament containing the scaffold ingredients and 3D printing the scaffold by fused filament fabrication. If bacteria is present, the Ag ions damage the bacterial cell envelope, nucleic acids, and inhibit the activity of specific proteins. The technology has been tested in vitro and demonstrated up to 6-log reduction in MRSA concentration when used in conjunction with antibiotics not typically effective when used alone. In vivo mice studies have also shown improved bone growth in bone defects and reparative dentin formation and enhanced preservation of vital pulp tissue.

BENEFITS

Effective against resistant bacteria including MRSA
Controlled release of silver provide for localized concentrations that are lethal to bacteria but not the host
Synergistic with existing antibiotics and restoring the sensitivity of antibiotic MRSA resists
Improved bone growth and dentin formation
Compressive strength is in the range of cancellous bone
Promotes bone tissue growth. Suitable for load bearing application

APPLICATIONS