PROJECT SUMMARY
Each year there are over two million healthcare-associated infections as a result of indwelling device
infections in the United States alone, from which approximately 99,000 people die. Antibiotic-resistant biofilms
thus create numerous problems in both medical and biomedical applications and have profound negative
implications for public health. To tackle this problem, “smart”, antibiotic-free, anti-infection polymer brush
biocoatings (sPBBs), designed specifically for catheters have been developed. In this study, we have utilized the
innovative plasma-assisted free radical graft polymerization technique for the construction of sPBBs. These
smart biocoatings consist of ammonium polymer brushes that sense bacteria and biofilms and effectively target
the infectious organisms discriminately, while promoting tissue cell growth. Mechanistic studies involving sPBBs
demonstrate a complex activity, triggered by adherent bacteria. We propose that our anti-infection biocoatings
may be the future for the prevention of medical and biomedical implant contaminations. Preliminary data suggest
that sPBBs are efficacious for eradicating antibiotic-resistant, biofilm-forming bacteria including methicillin-
resistant Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli on biomaterials used to
make catheters, in vitro. Several possible advantages of sPBBs in comparison to traditional anti-bacterial
surfaces loaded with antibiotics or antibacterial agents are (1) their broad spectrum of activity against antibiotic
resistant bacteria, (2) the unlikelihood of bacterial resistance, (3) specificity, (4) stability, and (5) longevity.
Three integrated specific aims are proposed to test the hypothesis that sPBBs can be fabricated using the
plasma-initiated surface graft polymerization technique and are efficacious at preventing infections in a medically
relevant environment. In Specific Aim 1, experimental variables will be explored to construct stable sPBBs with
increased sensitivity to biofilm formation. In Specific Aim 2, the anti-infection efficacy of sPBBs will be evaluated
against several different gram-positive and gram-negative biofilm-forming strains of bacteria in vitro, as well as
in a microfluidic cultivation system, designed specifically to model the actual environment of catheters. An
exploration of the mechanism of action with a focus on the induction of bacterial cell lysis in complex biological
systems will be studied by using different viability assays. Specific Aim 3, will facilitate the other two aims and
evaluate the in vitro specificity of sPBBs against human tissue cells in co-culture. This research seeks to improve
upon existing techniques for the eradication of infections associated with medical and biomedical devices. This
work and AREA program funding will also enhance the undergraduate research program at Saint Peter’s
University by providing students with opportunities to apply theoretical knowledge to practical, hands-on scientific
applications.