Graduation Semester and Year
Summer 2024
Language
English
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Biomedical Engineering
Department
Bioengineering
First Advisor
Kytai T. Nguyen, Ph.D.
Second Advisor
He Dong, Ph.D.
Third Advisor
Liping Tang, Ph.D.
Fourth Advisor
Jun Liao, Ph.D.
Fifth Advisor
Hao Xu, Ph.D.
Abstract
Healthcare-associated infections have a prevalence of about 7% in the United States and up to 50% in some developing nations. They not only present a constant risk for inpatients and healthcare workers but are also a serious challenge to human health services worldwide. These infections can be transmitted via contaminated non-critical surfaces like doorknobs and bedrails, which are routinely cleaned with low-level disinfectants approved by the U.S. Environmental Protection Agency. However, this strategy has limited efficacy since recontamination occurs, resulting in these surfaces again becoming vectors of infection. In this work, we addressed this issue by developing a self-disinfecting nanocomposite to continuously sanitize metallic, non-critical nosocomial surfaces under artificial illumination or in the dark. The material was formulated with photocatalytic nanoparticles and silicate binders for environmentally friendly application and sustained antibacterial activity. Applied as a 20-micron coating onto aluminum surfaces and assessed against either S. aureus or E. coli, the nanocomposite reached more than 4 log10 reduction in 60 minutes, exceeding the requirements from the Environmental Protection Agency for antimicrobial surface coatings (minimum 3 log10 reduction within 1 to 2 hours). Furthermore, after 500 wet abrasion cycles, the material demonstrated its durability by attaining a 3.4 log10 reduction in 60 minutes against S. aureus. Additionally, the nanoparticles demonstrated good cytocompatibility, and the nanocomposite was classified as a non-irritant by the Organization for Economic Co-operation and Development Test No. 439, ensuring its safety for human skin contact. Our results suggest that this newly developed material has the ability to complement and reinforce the current infection prevention strategies applied in the nosocomial setting. Future work includes evaluating the efficacy of this material against clinically relevant hospital-acquired microorganisms.
Keywords
Hospital-associated infections, Hospital-acquired infections, Nosocomial infections, Antimicrobial coatings, Antibacterial coatings, Self-disinfecting coatings, Photocatalytic coating, High touch surfaces, Frequently-touched surfaces, Nanocomposites
Disciplines
Biomaterials | Biomedical Engineering and Bioengineering
License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Recommended Citation
Soto Garcia, Luis Fernando, "DEVELOPMENT OF ANTI-MICROBIAL NANOCOATINGS ON METALLIC SURFACES TO PREVENT INFECTIONS" (2024). Bioengineering Dissertations. 123.
https://mavmatrix.uta.edu/bioengineering_dissertations/123
Comments
This work was supported by the National Institutes of Health (Grants F31 AI 169954 & T32 HL 134613), the UT Arlington STEM Doctoral Teaching Assistant Fellowship, the Alfred and Janet Potvin Scholarship, and the Franklin Alexander Scholarship.
Conflict of Interest Disclosure: Luis Fernando Soto Garcia has a potential research conflict of interest due to a financial interest in Active BioMed LLC. A management plan has been created to preserve objectivity in research in accordance with UTA policy.