Science and Mathematics Faculty Presentations

Effect of a Novel Zinc Porphyrin against Pseudomonas aeruginosa Biofilms Attached to Different Substrata

Document Type


Event Date



Brother Joseph W. Stander Symposium - University of Dayton


Dayton, Ohio, United States of America


Clearance of surface attached biofilms produced by bacterial colonization remains a relevant challenge in both industrial, and the biomedical communities. The difficult eradication of these biofilms rests in that bacteria produce an extracellular matrix that encases the cells; this acts as a scaffold for growth and imparts a form of protection. The matrix promotes resistance to treatment by physically blocking the passage of antibiotics to the bacterial cells. Work in our lab has produced a patented zinc porphyrin (ZnPor) which has the ability to disrupt attached biofilms on polyethylene by interacting with the base pairs of extracellular DNA found in the matrix. Biofilms disturbed by this porphyrin have been shown to become highly sensitive to antibiotics that previously had little to no effect. The objective of this project was to analyze the effect of ZnPor on removing biofilms attached to different surfaces. These data will set the stage for effective treatment of biofilms attached on a wide range of substrata: polyethylene (used in catheters), titanium (used in biomedical implants), hydroxyapatite (similar to bone) and borosilicate glass (control). This will be done by forming substrata into small coupons that will be placed into a CDC approved bioreactor. Pseudomonas aeruginosa will be inoculated into the bioreactor, and biofilms formed by 16~ 18 hours will then be treated by ZnPor followed by various antibiotics. The biofilms will be imaged with a LIVE/DEAD stain and analyzed by confocal laser scanning microscopy. The significance of our novel approach to antimicrobial management is that, unlike other protocols involving biofilm eradication, our strategy addresses the issue of resistance. The ability to disrupt the inherent matrix structure of biofilms and make cells accessible to antibiotic treatment promotes little resistance. Additionally, it decreases bacterial success in colonization of biomaterials and associated mortality rates in immunocompromised individuals.