479979 Antimicrobial Peptide Amphiphiles (AMPA) As a Surface Coating for Endotracheal Tubes

Monday, November 14, 2016
Grand Ballroom B (Hilton San Francisco Union Square)
Julie Nguyen1, Josiah Smith1, Alexis Dadelahi2, Fabio Gallazzi3, Brittany Angle4, Kenneth Gruber4, Roger de la Torre5 and Bret Ulery1,6, (1)Chemical Engineering, University of Missouri, Columbia, MO, (2)Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, (3)Research Core Facilities, University of Missouri, Columbia, MO, (4)Tensive Controls, Inc, Columbia, MO, (5)Division of General Surgery, University of Missouri, Columbia, MO, (6)Bioengineering, University of Missouri, Columbia, MO

Pneumonia accounts for greater than one-quarter of all hospital acquired infections, 86% of which originate from the use of endotracheal tubes (ETTs) for medical ventilation. Essentially, ventilator associated pneumonia is a significant health risk associated with the use of ETTs. To prevent bacteria colonization of ETTs, nano-etching and silver nanoparticle coatings have shown some promise but are very expensive, costing as much as 45 times the manufacturing cost of the ETT itself. A more affordable and possibly more potent alternative to these expensive technologies is the use of antimicrobial peptides (AMPs). While exciting, peptides are commonly unstable in harsh environments and can lose their functionality once immobilized. Additionally, due to their cationic nature, antimicrobial peptides are generally hydrophilic facilitating their rapid wash off from surfaces under humid or hydrated conditions. To address some of the challenges associated with peptides, antimicrobial peptide amphiphiles (AMPAs) consisting of an antimicrobial peptide tethered to a fatty acid have been explored for their capacity to prevent bacterial colonization of ETTs. Our results show that solvent evaporation and immersion coating yields AMPA films, which were confirmed by atomic force microscopy. The films were found to be relatively stable in the presence of phosphate-buffered saline, but they rapidly dissociated in pure methanol, a known co-solvent for both components of the AMPA. These data support the theory that the films are self-assembled in nature with the hydrophobic fatty acid tail interacting with the moderately hydrophobic polyvinylchloride of the ETT. Interestingly, when assessed for their antimicrobial properties, AMPA films were found to possess similar bioactivity to soluble AMP providing significant evidence that the deposition process and immobilization method did not negatively impact AMP bioactivity. Time variance studies and deposition solvent modifications are currently being investigated in order to optimize the coating process to yield the most potent self-assembled AMPA coatings.

Extended Abstract: File Not Uploaded