Bacterial adhesion to surfaces such as medical devices causes approximately 1.7 million infections and 75,000 deaths each year in the United States. Throughout the past several years, many studies have been conducted on micro- and nanostructure-enabled antimicrobial surfaces. However, this idea is controversial, as some studies have shown that superhydrophobic micro and nanostructures cannot prevent bacterial growth over time and that they are not a practical solution to reduce healthcare-related infections. The objective of this study is to develop a mechanically durable and long-lasting antimicrobial surface to prevent bacterial growth. High-aspect-ratio micro mushroom structures are fabricated by high resolution stereolithography and coated with Teflon and zinc oxide. To test the long-term antimicrobial efficiency of these structures, Escherichia coli is grown on the bare, Teflon-, and zinc oxide nanoflower-covered micro mushrooms for 12, 24, and 48 hrs. Bacterial growth is quantified using scanning electron microscopy. Surprisingly, over the 48-hr bacterial growth period, the zinc oxide-coated chips are the most effective, with no bacterial colonies and very little cell attachment. These results pave the way to enable a multi-scale hierarchical antimicrobial surface to combat healthcare-induced infections.

Library of Congress Subject Headings

Nosocomial infections--Prevention; Hydrophobic surfaces--Materials; Microfungi; Zinc oxide--Testing; Polytef--Testing

Publication Date


Document Type


Student Type


Degree Name

Mechanical Engineering (MS)

Department, Program, or Center

Mechanical Engineering (KGCOE)


Ke Du

Advisor/Committee Member

Blanca Lapizco-Encinas

Advisor/Committee Member

Howard Tu


RIT – Main Campus

Plan Codes